LM Technologies LM074 Users Manual

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LM074

SPP with GAP Central Application

USER GUIDE

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LM074 SPP with GAP Central Application v1.1

Revision

Date

Changes Description

v1.0

17/11/2017

First revision of this document.

v1.1

25/09/2018

Added firmware revision history and LED indication information.

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LM074 SPP with GAP Central Application v1.1

Contents

1. Introduction ......................................................................................... 7

2. Functionality of SPP with GAP Central application .............................. 7

3. LM074 GAP Central Role ...................................................................... 8

3.1 GAP Central AT commands in brief ...................................................... 9

3.2 Enable GAP Central functionality: ...................................................... 11

3.3 BLE discovery commands: ................................................................ 12

3.4 BLE security commands: ................................................................... 15

3.5 BLE connection commands: .............................................................. 16

3.6 BLE Services/characteristic scan commands: ....................................... 20

3.7 BLE read data from Characteristic: .................................................... 22

3.8 BLE write data on Characteristic: ....................................................... 26

4. LM074 AT commands and Default configuration ............................... 32

4.1 AT commands .................................................................................. 33

4.2 Module Settings commands: .............................................................. 35

4.3 UART Settings commands: ................................................................ 39

4.4 Bluetooth Security Settings commands: .............................................. 42

4.5 SPP Related commands: ................................................................... 45

4.6 Firmware Upgrade commands: .......................................................... 49

5. LM074 Over The Air Firmware Upgrade Procedure ......................... 50

5.1 Pre-requisites for Firmware upgrade: ................................................. 50

5.2 Firmware upgrade procedure Flow chart: ........................................... 51

5.3 Possible Failure points and corrective actions ...................................... 53

6. Simple Secure Pairing between LM074 and remote device ............. 61

6.1 Pairing of LM074(BT2.1) with BT2.0 devices ....................................... 61

Pairing of LM074 (BT2.1) with BT2.1 devices ...................................... 61

6.2

7. LED Indication ................................................................................. 64

7.1 Power on LED sequence ................................................................... 64

7.2 LED0 ............................................................................................... 64

7.3 LED1 ............................................................................................... 64

7.4 LED2 ............................................................................................... 65

7.5 Pairing State ..................................................................................... 65

8. Appendix ......................................................................................... 66

8.1 Abbreviations ................................................................................... 66

8.2 BLE Peripheral characteristics ............................................................ 66

8.3 GATT UUID type .............................................................................. 67

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LM074 SPP with GAP Central Application v1.1

8.4 GATT_Status_code ........................................................................... 68

8.5 BLE Service UUIDs ........................................................................... 70

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LM074 SPP with GAP Central Application v1.1

Table of Figures

Figure 1: Firmware Upgrade Flowchart ............................................................... 52

Figure 2: UART messages when the module is not connected to the peer device ... 55 Figure 3: UART messages when the module opens a partition to write new image . 56

Figure 4: UART messages when the CRC of the received image does not match .... 58

Figure 5: UART messages showing a failure in image verification .......................... 59

Figure 6: UART messages showing successful firmware upgrade .......................... 60

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LM074 SPP with GAP Central Application v1.1

Firmware Revision History

Version:0107

1. Up to Version_0106, the device will indicate the input pairing request to use and process it as per the Accept or Reject response from the user.

2. In Version_0107, this dependency is removed (like the LM048) and the device will accept all the pairing requests. The device will indicate the success or failure of the pairing procedure.

Version:0107 – Recreated images for Ver_0107 – 20

June 2018

1. The images were recreated, the SPP_ESC_Sequence timeout is 2 seconds.

2. Other features are the same.

3. LM961 tested again with the LM154 test tool, passed the test successfully.

4. Added all production and OTA bin images.

Version:0108 – 29

June 2018

1. Version _0108 released for LM961/LM074 and LM068.

2. Bug fix – LM961/LM074/LM068 was not connecting to the WIN-PC after a successful pairing. The RFCOMM-Serial-Over-Bluetooth ports were not being created, and the error “device not supporting Serial service” was displayed on the PC. This was resolved by adding the default SDP record from CSRExample-code.

3. Added production and OTA bin images for all devices.

Version:0109 – 19

Sept 2018

1. Version _0109 released for LM961/LM074 and LM068.

2. LED Blinking was modified to be similar to the LM048 LEDs. Blue LED Blinking if Not connected. Yellow LED as LINK-Data-Transfer LED.

3. Escape sequence detection logic was also modified to be similar to the LM048.

4. Added the feature to upgrade the device name using the last two bytes of the BD-Address. Set as default True. Users can turn it OFF using the AT command AT*UpdateName=ON/OFF.

5. The name of the LM068 adapter is 068SerialADTxx, xx are the last two bytes of BD-address.

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LM074 SPP with GAP Central Application v1.1

1. Introduction

This document describes the functionality of the “SPP with GAP Central” application.

1. SPP with GAP Central application specific AT commands and information

2. All AT commands and default configurations on device

3. Over the Air Firmware Upgrade procedure

4. Secure simple pairing procedure

The LM074 is a dual mode module with the capability for simultaneous connections to Bluetooth (v1.0 – v3.0), and Bluetooth low energy devices. LM Technologies supports various firmware applications on the LM074 module enabling users to develop their own applications with AT commands.

2. Functionality of SPP with GAP Central application

In the SPP with GAP Central application the LM074 can either be a SPP Master or Slave; or dual mode with one SPP connection at a time. The SPP role supports BOND, ACON, and features similar to those of LM Technologies’ legacy products such as the LM048, LM072 and LM400,

For Bluetooth low energy, it will be in the GAP Central role and can establish connections to up to five low energy peripherals simultaneously. Users can have a maximum of six active connections with this application (five low energy and one SPP). Data can be transferred between devices using AT commands.

For the Bluetooth low energy GAP Central role, the user can perform functions normally performed by Android tablets or phones. A user can discover nearby Bluetooth low energy peripherals, and up to ten devices will be reported. They can then connect to any of those devices and read or write data on various services or characteristics with the help of AT commands. The Bluetooth low energy connection also supports whitelisting. If you add the paired devices to the whitelist it will only report advertising packets from the devices added to the whitelist, or only connect to devices on the whitelist.

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LM074 SPP with GAP Central Application v1.1

3. LM074 GAP Central Role

This section describes the AT commands for the GAP Central role to initiate a connection, pair, whitelist, or read/write data to a BLE peripheral device. AT commands for the SPP role and generic device configuration are described in section 4 “LM074 AT commands and Default configuration”.

Every command is terminated with “CR-LF”. The module will begin parsing the AT command string after receiving the “CR-LF” sequence.

For every AT command issued by a user via UART the module responds with OK/ERR. If the user issues an incorrect AT command string (e.g. instead of "AT*Settings=?" the user issues "AT*Setting=?"), or issues a correct AT command string but in an invalid state (e.g. the user issues a connection command "AT*CONN=001122334455" while the SPP-role is Slave), the module will respond with ERR.

AT commands are used to enable or disable the GAP Central role of the module. By default, this mode is disabled and the module only initiates the SPP functionality. To enable GAP Central functions, use the AT command AT*ENBGAP=ON. The module will perform a soft reset and initialize itself with both SPP and GAP Central functions initialized. When the module has the GAP Central role disabled, for every AT command of GAP Central functionality or settings, module will respond with “ERR”.

When the module is in the GAP Central role it supports BLE device discovery, connection initiation, and reading/writing data. Users can use different AT commands to read/write data on BLE peripherals or receive updates from BLE peripherals via UART.

The SPP with GAP Central application enables the SPP and BLE connections. If the module is in the slave role it is ready to accept an SPP connection at any moment. If the user application only requires GAP Central roles, then set the SPP role as Master and ACON as OFF. This means that module will only connect to a remote SPP device when the connection is initiated by the LM074 module with an AT command.

If the user application requires a SPP connection with ACON ON and BLE connections it’s possible that the LM074 might connect with a remote SPP master device while reading/writing data on the BLE Peripheral, or while performing some other task. This will be indicated to user with “IND*:CONNECTED=001122334455”. If so the user should use the escape sequence i.e. +++ to come out of SPP-Online-Connected mode and then issue the required AT commands.

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LM074 SPP with GAP Central Application v1.1

Sr no

AT command string

Command type

Default setting

AT command format for reference

“AT*ENBGAP”

Query and Set

OFF

AT*ENBGAP=? AT*ENBGAP=ON AT*ENBGAP=OFF

“AT*LESEC”

Query and set

OFF

AT*LESEC=ON / AT*LESECOFF /ATLESEC=?

“AT*GETCID”

Query only

- 4

“AT*LEFIND”

Execution only

AT*LEFIND=ON AT*LEFIND=OFF

“AT*LECONN”

Execution only

AT*LECONN=001122334 455

“AT*LEDROP”

Execution only

AT*LEDROP=001122334 455

“AT*ENBCCFG”

Execution only

AT*ENBCCFG=CID,CHAR

-Handle e.g. At*enbccfg=5,0019

8 “AT*BLECONN ”

Query only

AT*BLECONN=?

9 “AT*INDRESP”

Execution only

AT*INDRESP=CID e.g. At*indresp=5

10 “AT*FINDSERV ”

Execution only

AT*FINDSERV=CID e.g. At*findserv=5

11 “AT*FINDCHA R”

Execution only

AT*FINDCHAR=CID,Start

-Handle,End e.g. At*findchar=5,0001,ffff

“AT*CLRWHIT E”

Execution only

“AT*CLRWHITE”\r\n

3.1 GAP Central AT commands in brief

The table below shows the AT commands for the GAP Central role with examples for reference.

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-Handle

LM074 SPP with GAP Central Application v1.1

Sr no

AT command string

Command type

Default setting

AT command format for reference

“AT*WRWORE SP”

Execution only

AT*WRWORESP=CID,Ch ar bytes,actualbytes e.g. at*wrworesp=5,0012,14, 01234567890123456789

“AT*RDCHARV AL”

Execution only

AT*RDCHARVAL=CID,ch ar e.g. At*rdcharval=5,0020

“AT*WRCHARV AL”

Execution only

AT*WRCHARVAL=CID,ch ar bytes,actualbytes e.g. at*wrcharval=5,0012,14, 01234567890123456789

“AT*LEAUTOS CAN”

Query and Set

AT*LEAUTOSCAN=ON AT*LEAUTOSCAN=OFF AT*LEAUTOSCAN=?

“AT*RDMULTC HAR”

Execution only

AT*RDMULTCHAR=CID,n o handle1,char 2,char handle4, char e.g. At*rdmultchar=5,05,000 3,0005,0008,0008,000a

“AT*RDLONGC HAR”

Execution only

AT*RDLONGCHAR=CID, Char e.g. at*rdlongchar=5,0029

“AT*SIWRWO RESP”

Execution only

AT*SIWRWORESP=CID, Char bytes,actual e.g. at*siwrworesp=5,0028,1 4,0123456789012345678 9

-Handle,no-of-

-handle

-handle,no-of-

-of-read,char-

-handle-

-handle3,char-

-handle5

-Handle

-Handle,no-of-

-bytes

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LM074 SPP with GAP Central Application v1.1

3.2 Enable GAP Central functionality:

3.2.1 “AT*ENBGAP”\r\n

i. Query and Set command.

ii. To query settings use the command “AT*ENBGAP=?” \r\n

iii. Response to the query command will be “OK”/”ERR” and report

will be “REP*:GAP_ENABLE=ON” or “REP*:GAP_ENABLE=OFF”

iv. By default, this setting is OFF i.e. the GAP Central role is disabled.

The module is only initialized for the SPP functionality.

v. To enable the GAP Central role, use the command

“AT*ENBGAP=ON”.

vi. The module will respond with OK and display the message

“Module soft-Reset..” to indicate that the module is performing a soft reset to enable the GAP Central role.

vii. After reset, the module shows the power on sequence

“SPP+GapCentral_Message_Loop”

viii. If the module currently has ENBGAP set to OFF, and command is

issued to turn it OFF, the module shows an ERR response. Similarly, if the current setting is ON and the command is issued to turn it ON, the module will output an ERR response.

ix. Response of the “AT*SETTINGS=?” query command depends on

the ENBGAP setting.

x. Response of the AT*SETTINGS=? Command displays the settings

of LESEC, LE-Auto-Scan only if the ENBGAP is ON.

SPP+tral_Message_Loop

at*enbgap=?at*enbgap=?

OK REP*:GAP_ENABLE=OFF

at*settings=?at*settings=?

OK NAME=LM074_GAP_Central ADDR=0002-5b-00a5a5 FLOW=OFF SPPRole=SLAVE ACON=OFF BOND=0000-00-000000 DPIN=OFF PIN=1234 GAP_ENABLE=OFF VER=074LM_GAPCEN_01.06 REP*:SETTINGS=END

at*enbgap=offat*enbgap=off

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LM074 SPP with GAP Central Application v1.1

ERR

at*enbgap=onat*enbgap=on

OK Module soft-Reset..SPP+GapCentral_Message_Loop

GATT Initialised REP*:LESEC=Success

at*settings=?at*settings=?

OK NAME=LM074_GAP_Central ADDR=0002-5b-00a5a5 FLOW=OFF SPPRole=SLAVE ACON=OFF BOND=0000-00-000000 DPIN=OFF PIN=1234 GAP_ENABLE=ON LE_SEC=OFF LE_AUTO_SCAN=ON VER=074LM_GAPCEN_01.06 REP*:SETTINGS=END

at*enbgap=?at*enbgap=?

OK REP*:GAP_ENABLE=ON

at*enbgap=onat*enbgap=on

ERR

at*enbgap=offat*enbgap=off

OK Module soft-Reset..SPP+GapCentral_Message_Loop

3.3 BLE discovery commands:

3.3.1 “AT*LEFIND”\r\n

i. Execution only command.

ii. To begin discovery of nearby BLE peripheral devices, use the

command “AT*LEFIND=ON”\r\n

iii. The module responds with OK to this command if it is not already

scanning the devices, otherwise it responds as “ERR”.

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LM074 SPP with GAP Central Application v1.1

iv. The module reports the name and BT address of the device as

soon as it finds the advertisement packet and keeps on updating the report as devices are discovered.

v. The module stops the BLE scanning process when it finds 10 BLE

devices and displays END of report message.

vi. There is no time limit set in the firmware to end the BLE scanning

process. If the user wants to terminate the scanning process, they should issue the “AT*LEFIND=OFF” command.

vii. If the module is displaying the scan report and user issues a

connection request to any of the devices, then the scan is terminated and connection procedure is started.

viii. The module indicates the beginning and end of discovery response

as “REP*:BLE_SCAN_REP=START” and

“REP*:BLE_SCAN_REP=END” respectively.

ix. Below is an example report for BLE scanning:

“at*lefind=onat*lefind=on OK REP*:BLE_SCAN_REP=START = 1 :1028-00-5b0002 :0 = 2 :1032-00-5b0002 :0 = 3 :3333-33-333333 :0 = 0: 3333-33-333333, LM Serial Server = 4 :8863-df-be936c :0 :LML8 = 5 :0000-00-000000 :3 = 6 :1029-00-5b0012 :0 :CSR BP Sensor = 7 :1030-00-5b0012 :0 :CSR HR Sensor = 8 :1031-00-5b0012 :0 :CSR HR Sensor

at*lefind=offÑlefind=off at*lefind=offat*lefind=off

OK”

x. If the user terminates the scanning process by issuing the

“AT*LEFIND=OFF” command, the module responds to it with an OK/ERR message but it does not issue an end of report message.

xi. When the module finds a BLE advertising report, it does not show

the device in the report immediately, it waits for the advertising packet in which BLE-Device-name is included.

a. If the module finds address and name same packet, it

displays both.

b. If the module finds address only it shows address and

waits for name.

c. When the module finds name of the device for which it

has reported address previously, it will show name in report with the serial number as 0 to indicate this is not new device but only name is appended for the device already reported.

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LM074 SPP with GAP Central Application v1.1

xii. If the LM074 has setting “AT*LESEC=OFF”, LM074 reports BLE

devices even if not present in its Whitelist. If setting is “AT*LESEC=ON”, LM074 will only report advertising devices which are in its whitelist.

xiii. In the discovery report, after the BD-address there is an indication

for “advertising Indication type” ranging from 0 to 5 as mentioned below.

a. ble_adv_event_connectable_undirected = 0 =

Connectable Undirected Advert.

b. ble_adv_event_connectable_directed = 1 =

Connectable Directed Advert.

c. ble_adv_event_discoverable = 2 = Discoverable

advert.

d. ble_adv_event_non_connectable = 3 = Non-

connectable. e. ble_adv_event_scan_response = 4 = Scan Response. f. ble_adv_event_unknown = 5 = Unknown event type.

xiv. The LM074 SPP with GAP central application also supports SPP

connection. The module may establish a SPP connection while performing LE discovery. When the module connects with the SPP device, it enters in SPP-Data mode and shows data from the remote device on UART. It treats data sent on local UART as data to be sent to remote device. To access UART for commands and responses, the user needs to use the escape sequence and then continue with other AT commands.

xv. Refer to the screenshots below.

at*lefind=onat*lefind=on

OK REP*:BLE_SCAN_REP=START = 1 :1032-00-5b0002 :0 = 2 :1028-00-5b0002 :0 = 3 :3333-33-333333 :0 = 0: 3333-33-333333, LM Serial Server = 4 :8863-df-be936c :0 :LML8 IND*:CONNECTED=0012-6f-0819c2 +++OK = 7 :2053-ca-20126e :0 = 8 :2053-ca-20126f :0

at*lefind=offat*lefind=off

xvi. Data during the SPP connection and receive of escape command is

lost in this report (data is lost as UART is given to SPP connection).

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LM074 SPP with GAP Central Application v1.1

3.4 BLE security commands:

3.4.1 “AT*LESEC”\r\n

i. Query and Set command.

ii. LESEC stands for Low Energy Security i.e. whether to apply

whitelist security or not. iii. Query command to query the setting is “AT*LESEC=?”\r\n. iv. Query report is “REP*:LE_SEC=OFF”\r\n or

“REP*:LE_SEC=ON”\r\n.

v. When LESEC is ON, the module will scan advertising packets only

from whitelist added devices and connect to the devices already

added to whitelist (i.e. already BLE paired devices) vi. When LESEC is OFF, the module will scan and connect to any BLE

discoverable and connectable device (module will discover and

connect any device even if it is not paired with module before)

Note: If the LM074 wants to add a new device in its whitelist then

while establishing the connection with the device at first time user

should use setting “AT*LESEC=OFF”. This enables the

authentication procedure to start to add a new device to the white

list.

Once the module completes the pairing procedure successfully the

BLE device is added to the white list. Then the LM074 can use the

setting “AT*LESEC=ON” for further connections with the same

device.

3.4.2 “AT*CLRWHITE”\r\n

i. Execution only command.

ii. This command is used to delete all the devices from BLE paired

devices list i.e. White list. iii. Command format is “AT*CLRWHITE”\r\n iv. Module responds OK and deletes all the devices from the whitelist.

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LM074 SPP with GAP Central Application v1.1

3.5 BLE connection commands:

3.5.1. “AT*LEAUTOSCAN”\r\n

i. Query and set command.

ii. Enable or disable the feature to scan the connected BLE peer

device automatically for its services. iii. Low energy auto scan query: “AT*LEAUTOSCAN=?”\r\n. iv. Low energy auto scan query report:

“REP*:LE_AUTOSCAN_SERVER=ON” (Module default setting as

LE-Auto-Scan enabled)

v. Low energy auto scan enable command:

“REP*:LE_AUTOSCAN_SERVER=ON”\r\n. If LE Auto Scan is

enabled, after connection module starts scanning Peer device for

its services and characteristics automatically. vi. Low energy auto scan disable command:

“REP*:LE_AUTOSCAN_SERVER=OFF”\r\n. If disabled, module

does not scan the Peer device for its services and characteristics

automatically. Module will wait for AT*FindServ command from

user.

3.5.2 “AT*BLECONN”\r\n

i. Query only command.

ii. User can query how many BLE connections module is having and

details for those connections. iii. Command format is : “AT*BLECONN=?”\r\n iv. GAP Central application can have maximum 5 BLE connections

simultaneously.

v. Example report for this command shall be as shown below

at*BLECONN=?at*BLECONN=?

OK REP*:BLE_CONN = 1 : 3333-33-333333 : 0101 = 2 : 1030-00-5b0012 : 0182 = 3 : 1032-00-5b0002 : 0203 = 4 : Open = 5 : Open REP*:BLE_CONN END

vi. The report above shows that the module is now connected with

three devices. The report lists connection ID given by module,

remote device BD-Address and Connection-ID i.e. CID given by

BLE stack.

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LM074 SPP with GAP Central Application v1.1

vii. Start and end of report is mentioned.

viii. E.g. In above report, row “= 3 : 1032-00-5b0002 : 0203”

mentions module has 3rd connection with 1032-00-5b0002 device

and CID given by BLE stack is 0203. ix. CID given in above response is referred while reading/writing data

with AT commands, reporting disconnection, notification etc. User

should note this carefully.

x. Response to this module depends on current state of the module

for BLE connections. xi. In a scenario where module has established 3 connections as

shown above and if it drops connection 2 then the response to

command AT*BLECONN=? Will be

at*BLECONN=?at*BLECONN=?

OK REP*:BLE_CONN = 1 : 3333-33-333333 : 0101 = 2 : Open = 3 : 1032-00-5b0002 : 0203 = 4 : Open = 5 : Open REP*:BLE_CONN END

3.5.3 “AT*LECONN”\r\n

i. Execution only command

ii. GAP Central application gives more details on connection

parameters when connection is successful and error code value if

connection fails. iii. User need to mention the BD address of the remote device with

which the BLE connection is to be established, e.g.

“at*leconn=1031-00-5b0012”\r\n tries to establish connection

with “1031-00-5b0012” device. iv. Response to this command will be ERR if any of the following is

true

a. string format is incorrect b. BT address is invalid c. 5 BLE connections are already established

v. Response to this command will be OK if all the following

conditions are true

a. Command string format is correct b. BT address is valid c. Module has at least one BLE connection open

vi. After displaying OK response, module starts the BLE connection

procedure.

vii. If the connection is failed the report is given with the error code e.

g. “REP*:BLE_CONN_FAIL:=1031-00-5b0012,4

err_code:0014”\r\n.

viii. Refer the Error code list mentioned in the appendix section.

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LM074 SPP with GAP Central Application v1.1

ix. If the module is successfully connected to a remote device it will

show a report with details about the connection. E.g.

“REP*:BLE_CONNECTED:=1030-00-5b0012-0 : 1 : 0080 : 0017 :

0008”\r\n

x. Here report includes extra information for the connection details

as below.

a. 1030-00-5b0012 is BD address of the remote BLE device. b. -0 with the address mentions Address type of remote BLE

device.

c. TYPED_BDADDR_PUBLIC is noted as 0,

TYPED_BDADDR_RANDOM is noted as 1.

d. 1 indicates Connection ID given by LM074 module (refer to

BLEconn=? report). e. 0080 mentions CID given by BLE stack (hex value 0x0080). f. 0017 is MTU i. e. Maximum Transfer Unit for this BLE

connection (hex value 0x0017). g. 0008 is Connection configuration flag (hex value 0x0008)

xi. User should take note of MTU mentioned in connection report,

while reading and writing data on this device, using one command (rdcahval/wrworesp etc) up to MTU number of bytes can be sent/received. If user need to read/write more than MTU number of bytes, it needs two commands.

at*leconn=1030005b0012at*leconn=1030005b0012

OK REP*:BLE_CONNECTED:=1030-00-5b0012-0 : 1 : 0080 : 0017 : 0008 BLE Auth start OK REP*:SERVICE START: =1030-00-5b0012 = 1 : 1801 : 0001 : 0004 = 2 : 1800 : 0005 : 000b = 3 : 180d : 000c : 0013 = 4 : 180f : 0014 : 0017 REP*:BLE_PAIR=1030-00-5b0012,Success = 5 : 00001016d10211e19b2300025b00a5a5 : 0018 : 0021 = 6 : 180a : 0022 : ffff REP*:SERVICE END: =1030-00-5b0012

xii. BLE Pairing:

a. After module is connected with Peer device, If LESEC i.e. LE

Security is OFF, module starts BLE Authentication process and

Shows message “BLE Auth start” to indicate start of

authentication process. b. If LESEC is ON, module will report or connect to only with

previously Paired devices which are present in its whitelist. c. Pairing Success or Failure indication report is given to user as

“REP*:BLE_PAIR=1030-00-5b0012,Success” or

“REP*:BLE_PAIR=1030-00-5b0012,Fail” .

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LM074 SPP with GAP Central Application v1.1

d. After module completes the pairing procedure successfully,

module adds this device to its whitelist. e. Pairing procedure runs at the background and can show the

status of pairing at any time. e.g. above report shows the

pairing report has displayed while showing Service-scan

report.

xiii. If LEAutoScan server setting is ON then, module starts scanning

services supported on the remote device and displays the report. If LEAutoScan server setting is OFF, module waits for commands from user to scan the services (FINDSERV).

3.5.4 “AT*LEDROP”\r\n

i. Execution only command

ii. Command is used to disconnect the BLE connection. Command

requires peer devices BT address.

iii. BLE connection disconnection command format:

“AT*LEDROP=1030005b0012”\r\n

iv. Response for BLE drop connection will be OK if the module is

connected to the BLE device with the same address provided in Drop command.

v. Response for BLE drop connection will be ERR if the module is not

connected with any BLE device or BD address mentioned in the AT command is not same as the connected BLE device.

vi. Module shows a report for the disconnection command e.g.

at*ledrop=1030005b0012at*ledrop=1030005b0012

OK REP*:BLE_DIS_CONN:=1030-00-5b0012,2 err_code:0000

vii. Error code 0000 mentions the device has terminated connection

gracefully i.e. either device started disconnection procedure.

viii. Number 2 near the BD address mentions the BLE Connection ID

(refereed to BLEconn=? response).

ix. If disconnection is started by remote device or due to link loss the

indication for disconnection is shown as below with the reason code. “REP*:BLE_DIS_CONN:= 1030-00-5b0012,2 err_code:0019”

x. Refer to the error code in the appendix.

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LM074 SPP with GAP Central Application v1.1

3.6 BLE Services/characteristic scan commands:

3.6.1 “AT*FINDSERV”\r\n

i. Execution only command

ii. Command is used to scan services supported on connected BLE

device.

iii. User needs to state connection ID for the device whose services

are to be scanned. E. g. “at*findserv=1” finds services on 1st connected device.

iv. Module provides a detailed report for the services supported by

the remote device.

v. If the BLE device has any service with 128-bit UUID then it is

indicated with all bytes.

vi. IN below report the row mentions “ 1 : 1800 : 0001 : 0005 ”

where “1” is serial number, “1800” is 16bit UUID for service, “0001” is start handle of the service and “0005” is end handle of the service.

vii. Report is marked for start and end.

viii. For e.g refer below report.

at*findserv=1at*findserv=1

OK REP*:SERVICE START: =3333-33-333333 = 1 : 1800 : 0001 : 0005 = 2 : 180a : 0006 : 0016 = 3 : 00005500d10211e19b2300025b00a5a5 : 0017 : 001a = 4 : 180f : 001b : ffff REP*:SERVICE END: =3333-33-333333

3.6.2 “AT*FINDCHAR”\r\n

i. Execution only command

ii. Command used to scan characteristics supported by services on

the BLE device.

iii. User needs to mention connection ID for the device whose

services are to be scanned. And start and end handle of the services for which scan is to be performed.

iv. User can scan characteristics for only one service or multiple

services or for all services in single command.

at*findserv=1at*findserv=1

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LM074 SPP with GAP Central Application v1.1

v. Considering the above report for services, below are the possible

commands.

a. Scan characteristics of single service i.e. 1800 service,

handles are 0001 and 0005. Command should be

“AT*findchar=1,0001,0005”

b. Scan characteristics for first two services i.e. 1800 and 180a.

User shall issue command as “at*findchar=0001,0016”.

c. Scan characteristics of all services in single command, user

shall issue command “at*findchar=1,0001,ffff”.

vi. Report is marked for start and end.

vii. The example report below shows a characteristic scan command

report.

at*findchar=1,0001,001bat*findchar=1,0001,001b

OK REP*:CHAR start =1: 2a00 : 0003 : 02 : 0002 [ Rd ] =2: 2a01 : 0005 : 02 : 0004 [ Rd ] =3: 2a25 : 0008 : 02 : 0007 [ Rd ] =4: 2a24 : 000a : 02 : 0009 [ Rd ] =5: 2a23 : 000c : 02 : 000b [ Rd ] =6: 2a27 : 000e : 02 : 000d [ Rd ] =7: 2a26 : 0010 : 02 : 000f [ Rd ] =8: 2a28 : 0012 : 02 : 0011 [ Rd ] =9: 2a29 : 0014 : 02 : 0013 [ Rd ] =10: 2a50 : 0016 : 02 : 0015 [ Rd ] =11: 00005501 : 0019 : 14 : 0018 [ Wr_cmd CCFG ] REP*:CHAR END

viii. For report above, the row “=1: 2a00 : 0003 : 02 : 0002 [ Rd ]”

indicates “1” as serial number, “2a00” as 16 bit characteristic UUID, “0003” is characteristic handle, “02” is properties value and “0002” is declaration value for that characteristic.

ix. For details on Characteristic value and Declaration values refer

appendix A.

x. “=11: 00005501 : 0019 : 14 : 0018 [ Wr_cmd CCFG ]” row

indicates the characteristic has 128 bit UUID, but here only lower 32 bits are displayed. “0019” is characteristic handle. “14” is properties value, this characteristic has two properties as WR-cmd and CCFG. “0018” is declaration value for that characteristic.

xi. User needs to use characteristic-Handle to read or write data on

that characteristic.

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LM074 SPP with GAP Central Application v1.1

3.7 BLE read data from Characteristic:

3.7.1 “AT*RDCHARVAL”\r\n

i. Execution only command

ii. This command is used to read data from the BLE device for the

characteristic which has properties as read “Rd” i.e. 0x02. iii. The command format is “AT*RDCHARVAL=conn-ID, char-Handle”. iv. e.g. “at*rdcharval=1,0003” command is used to read data from 1

connected device, for characteristic 0003.

v. The module shall output an OK response if the CID and the Char-

handle is correct. vi. After the module gives OK response to read command, module

shows data received from remote device as a report.

vii. E.g. “REP*:RDCHARVAL=1:Rcvd_Bytes:0010 LM Serial Server” is

a report of read data for characteristic 0003.

viii. Report shows connection ID as 1, Received bytes as 0x10 i.e. 16

bytes, and the actual bytes are “LM Serial Server”. ix. If module receives an error response it is reported to user with the

error code.

x. Users can refer to error codes as mentioned in the appendix

section.

at*rdcharval=1,000cat*rdcharval=1,000c

OK REP*:RDCHARVAL=0001:Err_code:02

xi. Below show some reference reports for read command.

at*rdcharval=1,0003at*rdcharval=1,0003

OK REP*:RDCHARVAL=1:Rcvd_Bytes:0010 LM Serial Server

at*rdcharval=1,0005at*rdcharval=1,0005

OK REP*:RDCHARVAL=1:Rcvd_Bytes:0002

at*rdcharval=1,000aat*rdcharval=1,000a

OK REP*:RDCHARVAL=1:Rcvd_Bytes:0016 CSR-GATT-SERVER-MODEL-

at*rdcharval=1,000cat*rdcharval=1,000c

OK REP*:RDCHARVAL=0001:Err_code:02

xii. Above screenshots are taken on Hercules software on Windows

PC, it does not show non-printable characters in received

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LM074 SPP with GAP Central Application v1.1

response. If user analyse the RX line on Oscilloscope or protocol

analyser, all bytes can be seen.

3.7.2 “AT*RDMULTCHAR”\r\n

i. Execution only command

ii. This command is used to read data from multiple characteristic on

single remote device. iii. Read data from BLE device for the characteristic which has

properties as “Rd” i.e. 0x02. iv. Maximum of 5 characteristic’s data can be read in one single

command.

v. Command format is “AT*RdMultChar=conn-ID, no-of-chars-to-

read, char-Handle1, char-Handle2, char-Handle3, char-Handle4,

char-Handle5,”.

vi. e.g. command to read data from 3 characteristics shall be

“at*rdmultchar=1,03,0008,000a,0010” command is used to read

data from 1st connected device, on characteristic 0003, 0008 and

0010.

at*rdcharval=1,0008at*rdcharval=1,0008

OK REP*:RDCHARVAL=1:Rcvd_Bytes:0005 SR_no

at*rdcharval=1,000aat*rdcharval=1,000a

OK REP*:RDCHARVAL=1:Rcvd_Bytes:0006 mod_no

at*rdcharval=1,0010at*rdcharval=1,0010

OK REP*:RDCHARVAL=1:Rcvd_Bytes:0006 FW_Ver

at*rdmultchar=1,03,0008,000a,0010at*rdmultchar=1,03,0008

,000a,0010 OK REP*:RDMULTCHAR=1:Success length:0011 SR_nomod_noFW_Ver

vii. If the read number of bytes from characteristics exceeds than

MTU bytes then lower bytes are lost and only first MTU bytes are

reported. This is limitation of BLE stack and not of LM074

application.

viii. E.g. refer below response. (last bytes form 0003 characteristic are

lost while reading multiple characteristics in one command)

at*rdcharval=1,0008at*rdcharval=1,0008

OK © Copyright LM Technologies Ltd Page 23 of 70

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LM074 SPP with GAP Central Application v1.1

REP*:RDCHARVAL=1:Rcvd_Bytes:0005

SR_no

at*rdcharval=1,000aat*rdcharval=1,000a

REP*:RDCHARVAL=1:Rcvd_Bytes:0006

mod_no

at*rdcharval=1,0010at*rdcharval=1,0010

REP*:RDCHARVAL=1:Rcvd_Bytes:0006

FW_Ver

at*rdcharval=1,0012at*rdcharval=1,0012

REP*:RDCHARVAL=1:Rcvd_Bytes:0007

App_ver

at*rdcharval=1,000eat*rdcharval=1,000e

REP*:RDCHARVAL=1:Rcvd_Bytes:000b

CSR101x A05

at*rdmultchar=1,05,0008,000a,0010,0012,000eat*rdmultchar

=1,05,0008,000a,0010,0012,000e

REP*:RDMULTCHAR=1:Success length:0016

SR_nomod_noFW_VerApp_v

ix. Above screen shots are taken on Hercules software on Windows

PC, it does not show non printable characters in received response. If user analyse the RX line on Oscilloscope or protocol analyser, all bytes can be seen.

3.7.3 “AT*RDLONGCHAR”\r\n

i. Execution only command

ii. When the Characteristic Value is longer than can be sent in a

single Read Response message, user can use this command to read that value in one command.

iii. Read data from BLE device for the characteristic which has

properties as “Rd” i.e. 0x02.

iv. Command format is “AT*RdLongChar=conn-ID, char-Handle”.

v. Commands which support “rdcharval” can also be read by this

command.

vi. Response to the command shows bytes received, offset of current

data with respect to the whole data, and MoreToCome (MTC) flag if there is next data packet expected on the same characteristic read.

vii. Refer following read examples for more detail.

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at*leconn=333333333333at*leconn=333333333333

REP*:BLE_CONNECTED:=3333-33-333333-0 : 1 : 0100 : 0017

: 0008

BLE Auth start

REP*:SERVICE START: =3333-33-333333

= 1 : 1800 : 0001 : 0005

= 2 : 180a : 0006 : 0016

= 3 : 00005500d10211e19b2300025b00a5a5 : 0017 : 001a

= 4 : 180f : 001b : ffff

REP*:SERVICE END: =3333-33-333333

at*rdlongchar=1,0008at*rdlongchar=1,0008

REP*:RDLONGCHAR=1:0008:Success Rcvd:0005 Offset:0000

MTC:0

SR_no

at*rdlongchar=1,000aat*rdlongchar=1,000a

REP*:RDLONGCHAR=1:000a:Success Rcvd:0024 Offset:0000

MTC:0

abcdEFGHIJklmnopQRSTUvwxyz0123abcdEF

at*rdlongchar=1,000cat*rdlongchar=1,000c

REP*:RDLONGCHAR=1 Err_code:0002

at*rdlongchar=1,0005at*rdlongchar=1,0005

REP*:RDLONGCHAR=1:0005:Success Rcvd:0002 Offset:0000

MTC:0

at*rdlongchar=1,0003at*rdlongchar=1,0003

REP*:RDLONGCHAR=1:0003:Success Rcvd:0010 Offset:0000

MTC:0

LM Serial Server

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LM074 SPP with GAP Central Application v1.1

3.8 BLE write data on Characteristic:

3.8.1 “AT*ENBCCFG”\r\n

i. Execution only command.

ii. Command used to enable the Client-Configuration-Flag (CCFG) on

specific characteristic.

iii. When the module scans the characteristics of the device, it shows

the CCFG flag if supported by that characteristic. E.g Serial-OverGatt service supports this flag (highlighted yellow in below report).

iv. While issuing command, user should mention the device-

connection-ID and characteristic handle.

v. E.g The device 1 has CCFG flag characteristic with handle 0019.

To enable the CCFG flag use command “at*enbccfg=1,0019”.

vi. Module shall give OK response if the characteristic has CCFG flag

otherwise module shall give ERR response if wrong characteristic handle is mentioned.

vii. After the module responds with “OK”, the module receives

feedback from the BLE device regarding success or failure, which is reported to the user.

viii. The report “REP*:WRCHARVAL=1:Success” shows enable CCFG

operation is performed successfully.

at*findchar=1,0001,001bat*findchar=1,0001,001b

REP*:CHAR start

=1: 2a00 : 0003 : 02 : 0002 [ Rd ]

=2: 2a01 : 0005 : 02 : 0004 [ Rd ]

=3: 2a25 : 0008 : 02 : 0007 [ Rd ]

=4: 2a24 : 000a : 02 : 0009 [ Rd ]

=5: 2a23 : 000c : 02 : 000b [ Rd ]

=6: 2a27 : 000e : 02 : 000d [ Rd ]

=7: 2a26 : 0010 : 02 : 000f [ Rd ]

=8: 2a28 : 0012 : 02 : 0011 [ Rd ]

=9: 2a29 : 0014 : 02 : 0013 [ Rd ]

=10: 2a50 : 0016 : 02 : 0015 [ Rd ]

=11: 00005501 : 0019 : 14 : 0018 [ Wr_cmd CCFG ]

REP*:CHAR END

at*enbccfg=1,0019at*enbccfg=1,0019

REP*:WRCHARVAL=1:Success

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LM074 SPP with GAP Central Application v1.1

3.8.2 “AT*INDESPr\n

i. Execution only command.

ii. This command gives feedback to server/peripheral for notification

indication from server/peripheral.

iii. This command is used to acknowledge the sever that client(BLE-

Central) has received characteristic value Indication, and server(BLE-Peripheral) may send another indication.

iv. Command format is “at*INDRESP=Conn-ID”.

v. e.g. “AT*INDRESP=1” gives indication response for 1

connected

BLE device for receiving notification indication.

vi. OK/ERR response is given by LM074 after checking the Connection

ID and Connection status.

vii. After OK response is given Response is forwarded to remote

device by BLE-Stack.

viii. No feedback form BLE-Stack is provided to this command.

3.8.3 “AT*WRWORESP”\r\n

i. Execution only command

ii. This command is used to send data to BLE device for the

characteristic which has properties as “Wr_cmd” i.e. 0x04.

iii. Command format is “AT*WRWORESP=conn-ID, char-Handle,

length, actual-bytes ”.

iv. e.g. “at*wrworesp=1,0019,10,12345abcdef!()12” command is

used to send data to 1 No of bytes to write are 0x10 i.e. 16 and actual bytes are 1,2,3,4,5,a,b,c,d,e,f,!,(,),1,2.

v. As shown in the example command number of bytes to transmit is

hex value.

vi. As shown in the example command, actual data bytes are not

separated by a comma. When the value 0x31 is sent i.e. ASCII 1 is sent, the data buffer is copied and sent to remote device transparently.

vii. Note : The actual data bytes to be sent shall not have “\r\n” as

the data itself because it is the terminating string for AT command parser.

viii. For command “AT*WRWORESP=conn-ID, char-Handle, length,

actual-bytes” module gives OK response if all the following

conditions are true:

a. connection ID is correct (if module is connected to 3 devices

and CID mentions 4, then it is invalid) b. Characteristic handle has WR_cmd properties c. Value of “length” field is less than 21 i.e. (0x15). d. Actual data bytes are same as value of “length” field.

connected device, on characteristic 0019.

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LM074 SPP with GAP Central Application v1.1

ix. After the module responds to the command with “OK”, the module

sends the data to the remote BLE device.

x. If the remote device receives the data and sends feedback to the

LM074, that feedback is displayed on UART.

xi. E.g. report shows, “REP*:WRWORESP=1:0019:Success” which

indicates the data has been received by the remote device successfully. 1 is the CID-given by module and 0019 is the characteristic handle.

at*wrworesp=1,0019,05,12345at*wrworesp=1,0019,05,12345

OK REP*:WRWORESP=1:0019:Success

at*wrworesp=1,0019,10,12345abcdef!()12at*wrworesp=1,001

9,10,12345abcdef!()12 OK REP*:WRWORESP=1:0019:Success

3.8.4 “AT*WRCHARVAL”\r\n

i. Execution only command

ii. This command is used to send data to BLE device for the

characteristic which has properties as “Wr_req” i.e. 0x08.

iii. Command format is “AT*WRCHARVAL=conn-ID, char-Handle,

length, actual-bytes”.

iv. e.g. “at*WRCHARVAL=1,0019,10,12345abcdef!()12” command is

used to send data to 1 No of bytes to write are 16 (0x10) and actual bytes are

12345abcdef!()12.

v. As shown in the example command, no of bytes to transmit is hex

value

vi. As shown in the example command, actual data bytes are not

separated by comma. When the value 0x31 is sent i.e. ASCII 1 is sent, the data buffer is copied and sent to remote device transparently.

vii. Note : The actual data bytes to be sent should not have “\r\n” as

the data itself because it is the terminating string for AT command parser.

viii. For command “AT*WRWORESP=conn-ID, char-Handle, length,

actual-bytes” module gives OK response if all the following

conditions are true:

a. connection ID is correct (if module is connected to 3 devices

and CID mentions 4, then it is invalid) b. Characteristic handle has Wr_req properties c. Value of “length” field is less than 21 i.e. (0x15). d. Actual data bytes are same as value of “length” field.

ix. After module responds to this command as “OK”, module sends

the data to remote BLE device.

connected device, on characteristic 0019.

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LM074 SPP with GAP Central Application v1.1

at*findchar=2,0001,ffffat*findchar=2,0001,ffff

OK REP*:CHAR start =1: 2a05 : 0003 : 20 : 0002 [ Indi ] =2: 2a00 : 0007 : 0a : 0006 [ Rd Wr_req ] =3: 2a01 : 0009 : 02 : 0008 [ Rd ] =4: 2a04 : 000b : 02 : 000a [ Rd ] =5: 2a37 : 000e : 10 : 000d [ CCFG ] =6: 2a38 : 0011 : 02 : 0010 [ Rd ] =7: 2a39 : 0013 : 08 : 0012 [ Wr_req ] =8: 2a19 : 0016 : 12 : 0015 [ Rd CCFG ] =9: 00001013 : 001a : 0a : 0019 [ Rd Wr_req ] =10: 00001018 : 001c : 08 : 001b [ Wr_req ] REP*:CHAR END

at*wrcharval=2,0013,05,12345at*wrcharval=2,0013,05,12345

OK REP*:WRCHARVAL=2:Err_code:fd

at*wrcharval=2,0007,05,12345at*wrcharval=2,0007,05,12345

OK REP*:WRCHARVAL=2:Success

at*wrcharval=2,0007,05,abCDEat*wrcharval=2,0007,05,abCD

E OK REP*:WRCHARVAL=2:Success

at*wrcharval=2,001c,05,abCDEat*wrcharval=2,001c,05,abCDE

OK REP*:WRCHARVAL=2:Err_code:0d

at*wrcharval=2,001a,05,abCDEat*wrcharval=2,001a,05,abCD

E OK REP*:WRCHARVAL=2:Err_code:0e

at*wrcharval=2,0013,05,abCDEat*wrcharval=2,0013,05,abCD

E OK REP*:WRCHARVAL=2:Err_code:fd

x. If the remote device receives the data and sends feedback to the

LM074, that feedback is displayed on UART.

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LM074 SPP with GAP Central Application v1.1

xi. Above report shows the WRCharval command is successful only on

characteristic 0005 and 0007.

xii. If the WrCharVal command fails in execution, then the error code

reported by BLE-stack is reported to user in failure report. E.g. Err_code:fd , Err_code:0e, Err_code:0d

xiii. Refer Appendix section for more details on error code.

3.8.5 “AT*SIWRWORESP”\r\n

i. Execution only command

ii. This command is used to send data to BLE device for the

characteristic which has properties as “Si_Wrt” i.e. 0x40.

iii. Command format is “AT*WRCHARVAL=conn-ID, char-Handle,

length, actual-bytes”.

iv. e.g. “at*WRCHARVAL=1,0019,10,12345abcdef!()12” command is

used to send data to 1st connected device, on characteristic 0019. No of bytes to write are 16 (0x10) and actual bytes are

12345abcdef!()12.

v. As shown in the example command, no of bytes to transmit is hex

value

vi. As shown in the example command, actual data bytes are not

separated by comma. When the value 0x31 is sent i.e. ASCII 1 is sent, the data buffer is copied and sent to remote device transparently.

vii. Note : The actual data bytes to be sent should not have “\r\n” as

the data itself because it is the terminating string for AT command parser.

viii. For command “AT*WRWORESP=conn-ID, char-Handle, length,

actual-bytes” module gives OK response if all the following

conditions are true:

a. connection ID is correct (if module is connected to 3 devices

ix. After module responds to this command as OK, module sends the

data to remote BLE device.

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LM074 SPP with GAP Central Application v1.1

3.8.6 NOTIF_IND notification Indication

i. Indication given by module.

ii. When the module receives data from the remote BLE device, it

notifies the user on UART.

iii. E.g. the command below shows some indication reports:

IND*:NOTIF_IND=1:0019 R_bytes:0014 dataFromBLEDev123456

IND*:NOTIF_IND=1:0019 R_bytes:0003 789

IND*:NOTIF_IND=1:0019 R_bytes:0014 abcdefghijklmnopqrst

IND*:NOTIF_IND=1:0019 R_bytes:0006 uvwxyz

IND*:NOTIF_IND=1:0019 R_bytes:0014 abcdefghijklmnopqrst

IND*:NOTIF_IND=1:0019 R_bytes:0006 uvwxyz

iv. In report “IND*:NOTIF_IND=1:0019 R_bytes:0014

dataFromBLEDev123456” the module shows CID as 1,

Characteristic from which data is received is 0x0019, the actual received bytes are 0x0014, and then the actual bytes as “dataFromBLEDev123456”.

v. The module can receive a maximum of 20 bytes i.e. 0x14 bytes in

one notification packet.

vi. If the remote device sends more than 20 bytes in one packet then

the module shows two notification indication messages. E.g. if the remote device sends the string “dataFromBLEDev123456789”, the module shows “dataFromBLEDev123456” first and then “789”.

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LM074 SPP with GAP Central Application v1.1

4. LM074 AT commands and Default configuration

This section describes the AT command structure for the LM074 module.

Serial terminals (such as Hercules, HyperTerminal, Tera Term or Putty) can be used for serial communication with the LM074.

Every command is terminated with “CR-LF”. The module will begin parsing the AT command strings after receiving “CR-LF” sequence.

AT Commands are case insensitive e.g. “At*Resp=On”, “at*resp=on” and “AT*RESP=ON” are all valid.

AT command types:

1. Query only commands - Commands to query Module state, firmware version number etc.

2. Query and Set commands - Commands to query the setting and modify Module setting e.g. discoverability, Role, Baud, etc.

3. Execution only command – commands to perform specific action e.g. start discovery for Bluetooth devices, start connection procedure, start upgrade procedure etc.

The LM074 outputs messages to the user through the serial port for indications like connection/pairing request, result of connection/pair procedure, result of Bluetooth devices discovery, disconnection indication etc.

After the indication message is displayed, the LM074 waits for inputs from the user to execute further action. For example, after incoming pairing indications, enter accept/reject pair response or after indication for PASSKEY_cfm, provide yes/no confirmation for the passkey etc.

The module responds to each AT command as “OK”\r\n or “ERR”\r\n. After this response the module takes requested action or it will output report to the user on UART. If module does not receive “AT” as a start of new command, the module may not respond to this command even if it is terminated with “\r\n” (e.g. instead of “AT*NAME=?”, user issues “A*name=?”). Module will neglect the received string and is ready to receive new AT command and to process it.

When the module does not receive any command on UART for more than 30 seconds, the module enters deep sleep mode. The module can come out of this mode on UART activity or BT activity. If the user enters AT commands while the module is in deep sleep, the module may lose the first character of an AT command, e.g. for command “AT*NAME=?”, module may show the echo as “t*name=?” or “Ñname=?” i.e. some garbage character at start. The module will not respond to AT commands such as ERR/OK, but it ignores this data and waits for a new AT command to process.

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LM074 SPP with GAP Central Application v1.1

Sr no

AT command string

Command type

Default setting

AT*ADDR

Query only

AT*NAME

Query and set

Firmware version dependent e.g. 074LM_SPP_0106

AT*ECHO

Query and set

ON 4 AT*RESP

Query and set

AT*DCOV

Query and set

AT*PAIR

Query and set

ON 7 AT*STATE

Query only

-- 8 AT*VER

Query only

-- 9 AT*RESET

Execution only

AT*SETTINGS

Query only

Refer command details

Sr no

AT command string

Command type

Default setting

AT*BAUD

Query and set

19200 (5)

AT*PAR

Query and set

No parity (0)

AT*STOP

Query and set

One stop bit (0)

AT*FLOW

Query and set

Off

AT*CTS

Query only

AT*RTS

Set only

-- 7 AT*DTR

Set only

-- 8 AT*DSR

Query only

-- 9 AT*MODEM

Query and set

NONE

AT commands expects the BT address in the string. In this document “0126f357215” is considered a reference BT address, whereas 0012 is nap, 6f is uap and 357215 is lap in the BT address. Users should use the BT address of their devices.

4.1 AT commands

The table below shows all the AT commands that are supported on the LM074 module and the default settings wherever applicable.

4.1.1 General settings AT commands:

4.1.2 UART settings AT commands:

Note: CTS, RTS, DTR, DSR, MODEM commands are not applicable for LM074 module.

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LM074 SPP with GAP Central Application v1.1

Sr no

AT command string

Command type

Default setting 1 AT*PIN

Query and set

1234

AT*DPIN

Query and set

OFF

AT*MITM

Query and set

OFF

AT*IOTYPE

Query and set

NO_InOut

AT*DEL

Execution only

-- 6 AT*PASSKEY

Execution only

-- 7 AT*PASSCFM

Execution only

-- 8 AT*STOPPAIR

Execution only

-- 9 AT*PAIRLIST

Query only

Sr no

AT command string

Command type

Default setting 1 AT*FIND

Execution only

-- 2 AT*ROLE

Query and set

Dual

AT*ACON

Query and set

OFF

AT*CONN

Execution only

Escape sequence “+++”

Execution only

AT*AUTO

Execution only

-- 7 AT*DROP

Execution only

AT*BOND

Query and set

Default bond device address = 0000-00-000000

Sr no

AT command string

Command type

Default setting 1 AT*UPGRADE

Execution only

4.1.3 Bluetooth security settings commands:

4.1.4 SPP related AT commands:

4.1.5 Firmware Upgrade AT commands:

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4.2 Module Settings commands:

4.2.1 “AT*ADDR”\r\n

i. Query only command

ii. Address query: “AT*ADDR=?”\r\n

iii. Address query report: “REP*:ADDR=00025b00a5a5”

4.2.2 “AT*NAME”\r\n

i. Query and set command

ii. Name query: “AT*NAME=?”\r\n

iii. Name query report: “REP*:NAME=LM074_2_Default” iv. Name set command: “AT*NAME=testname”

v. Default name: (Depends on firmware version number)

4.2.3 “AT*ECHO”\r\n

i. Query and set command

ii. Echo query: “AT*ECHO=?”\r\n

iii. Echo query report: “REP*:ECHO=ON” or “REP*:ECHO=OFF” iv. Echo enable command: “AT*echo=on”

v. Echo disable command: “AT*echo=off”

vi. Default Echo: “ON”

4.2.4 “AT*RESP”\r\n

i. Query and set command

ii. Response query: “AT*RESP=?”\r\n

iii. Response query report: “REP*:RESP=ON” or “REP*:RESP=OFF” iv. Response enable command: “AT*RESP=on”

v. Response disable command: “AT*RESP=off”

vi. Default Response: “ON”

vii. When response is ON, the module responds as “OK” or “ERR” to

every command string before sending report/response of the command.

viii. When response is OFF, the module will not provide “OK” or “ERR”

reply to any AT command. This might not be helpful to users as the user will not get any response if incorrect AT command strings are entered.

ix. Below is the sequence of messages when ECHO and RESP are ON.

at*echo=?at*echo=? OK REP*:ECHO=ON at*resp=?at*resp=? OK

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LM074 SPP with GAP Central Application v1.1

REP*:RESP=ON at*name=?at*name=? OK REP*:NAME=068LM_SPP_0104

x. Below is the sequence of messages when ECHO is OFF and RESP

is ON.

at*echo=offat*echo=off OK at*echo=?OK REP*:ECHO=OFF at*resp=?OK REP*:RESP=ON at*name=?OK REP*:NAME=068LM_SPP_0104

xi. Below is the sequence of messages when ECHO and RESP are

both off. The module will show only reports for the query commands. The module will not show any indication messages for connect or disconnect. This is to ensure backwards compatibility with LM048/LM058/LM072 module firmware.

at*resp=?REP*:RESP=OFF at*echo=?REP*:ECHO=OFF at*name=?REP*:NAME=068LM_SPP_0104

4.2.5 “AT*DCOV”\r\n

i. Query and set command

ii. Discoverable query: “AT*DCOV=?”\r\n

iii. Discoverable query report: “REP*:DCOV=ON” (Module

discoverable for classic role) or “REP*:DCOV=OFF” (Module non discoverable for classic role)

iv. Module make discoverable command: “AT*DCOV=ON”

v. Module make non-discoverable command: “AT*DCOV=OFF”

vi. Default discoverability : “ON”

vii. Enabling discoverability may generate further events of incoming

pairing/connection requests.

4.2.6 “AT*PAIR”\r\n

i. Query and set command

ii. Pairable query: “AT*PAIR=?”\r\n

iii. Pairable query report: “REP*:PAIR=ON” (Module is in pairable

state and will give indications to host of any incoming pairing requests)

iv. Pairable query report: “REP*:PAIR=OFF” (Module is in non-

pairable state will reject pairing request internally)

v. Module make pairable command: “AT*PAIR=ON”

vi. Module make non-pairable command: “AT*PAIR=OFF”

vii. Default Pairable: ON

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LM074 SPP with GAP Central Application v1.1

viii. Enabling pair-ability may generate further events of incoming

pairing/connection requests.

ix. Module displays the message “IND*:PAIR=00126f357215” to

indicate that the device with BT-address 00126f357215 is requesting to pair.

x. To accept the pairing request the user should respond as

“AT*PAIR=00126f357215,accept”\r\n.

xi. To reject the pairing request user should respond as

“AT*PAIR=00126f357215,reject”\r\n.

xii. After pairing procedure is complete, module shows indication

message for success or failure of pairing

“IND*:PAIR=OK,00126f357215” or “IND*:PAIR=ERR,00126f357215” .

4.2.7 “AT*STATE”\r\n

i. Query only command

ii. Module state query: “AT*STATE=?”\r\n

iii. Module state query report: “REP*:STATE-DP=ON,ON” (“STATE-

DP” indicates states as D-discoverable is ON and P-Pairable is ON)

iv. Module state query report: “REP*:STATE-DP=ON,OFF” (“STATE-

DP” indicates states as D-discoverable is ON and P-Pairable is OFF)

4.2.8 “AT*VER”\r\n

i. Query only command

ii. Firmware version query: “AT*VER=?”\r\n

iii. Firmware version query report:

“REP*:VER=074LM_GAPCEN_01.06” (current firmware version

major number 1, minor number 04) string “074LM_GAPCEN” shows it is firmware on LM068 device with SPP profile.

4.2.9 “AT*RESET”\r\n

i. Execution only command, LM951/LM074 supports execution of

two “Reset” levels

ii. “AT*RESET=1”\r\n

1. Module applies soft reset, starts execution as if applied power on-off.

2. Retains all user modified settings

3. Causes disconnection for Bluetooth connections

iii. “AT*RESET=2”\r\n

4. Module applies hard reset

5. Loads default settings for all setting types

6. Causes disconnection for Bluetooth connections

7. Deletes all the paired devices and corresponding data

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LM074 SPP with GAP Central Application v1.1

“AT*Settings” report when DPIN is OFF

“AT*Settings” report when DPIN is ON

at*settings=?at*settings=? OK

NAME=

_SPP+GAPCEN _010 ADDR=0002 PAIR=ON DCOV=ON BAUD=19200(2) STOP=Stop_One(0) PARITY=None(0) FLOW=OFF SPPRole=SLAVE ACON=OFF BOND=0000 DPIN=OFF PIN=1234 GAP_ENABLE=OFF VER=

LM_GAPCEN_01.06

REP*:SETTINGS=END

at*settings=?at*settings=? OK

NAME=

_SPP+GAPCEN _010 ADDR=0002 PAIR=ON DCOV=ON BAUD=19200(2) STOP=Stop_One(0) PARITY=None(0) FLOW=OFF SPPRole=SLAVE

at*settings=?at*settings=? OK

NAME=

_SPP+GAPCEN _010 ADDR=0002 PAIR=ON DCOV=ON BAUD=19200(2) STOP=Stop_One(0) PARITY=None(0) FLOW=OFF SPPRole=SLAVE ACON=OFF BOND=0000 DPIN=ON MITM=OFF IOTYPE=NO_InOut GAP_ENABLE=OFF VER=

LM_GAPCEN_01.06

REP*:SETTINGS=END

at*settings=?at*settings=? OK

NAME=

_SPP+GAPCEN _010 ADDR=0002 PAIR=ON DCOV=ON BAUD=19200(2) STOP=Stop_One(0) PARITY=None(0)

4.2.10 “AT*SETTINGS”\r\n

i. Query only command

ii. Module settings query: “AT*SETTINGS=?”\r\n

iii. Report for “AT*SETTINGS=?” command is multiple line, at the end

of the report a message “REP*:SETTINGS=END” is delivered.

iv. Module settings query report varies according to DPIN setting. If

DPIN is OFF i.e. supporting to BT2.0, Module PIN is displayed. If DPI is ON, i.e. support to BT2.1, then settings for IO-capability, MITM are displayed.

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074

LM074

-5b-00a5a5

-00-000000

-5b-00a5a5

LM074

-5b-00a5a5

-00-000000

074

LM074

-5b-00a5a5

LM074 SPP with GAP Central Application v1.1

ACON=OFF BOND=0000

-00-000000 DPIN=OFF PIN=1234 GAP_ENABLE=ON LE_SEC=OFF LE_AUTO_SCAN=ON VER=074LM_GAPCEN_01.06 REP*:SETTINGS=END

FLOW=OFF SPPRole=SLAVE ACON=OFF BOND=0000

-00-000000 DPIN=ON MITM=OFF IOTYPE=NO_InOut GAP_ENABLE=ON LE_SEC=OFF LE_AUTO_SCAN=ON VER=074LM_GAPCEN_01.06 REP*:SETTINGS=END

Sr No

Actual baud rate

LM951 / LM074 baud rate code

Report from LM074

9600

“REP*:BAUD=9600(1) ”

19200

2 – Default baud rate

“REP*:BAUD=19200(2)”

38400

“REP*:BAUD=38400(3) ”

57600

“REP*:BAUD=57600(4)"

115200

“REP*:BAUD=115200(5)"

230400

“REP*:BAUD=230400(6)"

460800

“REP*:BAUD=460800(7)"

921600

“REP*:BAUD=921600(8)"

1382400

“REP*:BAUD=1382400(9)"

v. Also, Module response depends on ENBGAP settings. Refer section

1.2 “Enable GAP Central role” for more details.

vi. Actual values of PIN, MITM, IOTYPE are displayed as per the

current settings of device.

vii. Response to the settings command varies as per the device, e.g.

for LM068/LM074 modules it includes MODEM command.

4.3 UART Settings commands:

4.3.1 “AT*BAUD”\r\n

i. Query and set command

ii. Baud rate query: “AT*BAUD=?”\r\n

iii. Baud rate query report: “REP*:BAUD=19200(2)”. Number in curly

brackets shows the serial number as per below table.

iv. Baud rate set command: “AT*BAUD=3” (Set Module baud rate as

38400 bps)

v. Module need to not to perform power-on-off after change of baud

rate setting.

vi. Refer below table for baud rate settings:

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LM074 SPP with GAP Central Application v1.1

Sr No

Actual parity

LM951 / LM074 parity code

Report from LM074

Parity None

0 – default parity

“REP*:PARITY=None(0)”

Parity odd

“REP*:PARITY=Odd(1)”

Parity even

“REP*:PARITY=Even(2)”

Sr No

Actual Stop bit

LM951 / LM074 Stop bit code

Report from LM074

Stop bit One

0 – default stop bit

“REP*:STOP=Stop_One(0)”

Stop bit two

“REP*:STOP=Stop_Two(1)”

4.3.2 “AT*PAR”\r\n

i. Query and set command

ii. Parity query command: “AT*PAR=?”\r\n

iii. Parity query report: “REP*:PARITY=None(0)” (Module uses default

parity , parity = none). Number in curly brackets shows the serial number as per below table.

iv. Parity set command: “AT*PAR=1” (Set Module parity as odd)

v. Module need to not to perform power-on-off after change of parity

setting.

vi. Refer below table for parity settings:

4.3.3 “AT*STOP”\r\n

i. Query and set command

ii. Stop bit query command: “AT*STOP=?”\r\n

iii. Stop bit query report: “REP*:STOP=Stop_One(0)” (module uses

default stop bit as = one). Number in curly brackets shows the serial number as per below table.

iv. Stop bit set command: “AT*STOP=1” (Set module stop bit as two)

v. Module need not to perform power-on-off after change of parity

setting.

vi. Refer below table for stop bit settings:

4.3.4 “AT*FLOW”\r\n

i. Query and set command

ii. Flow control query command: “AT*FLOW=?”\r\n

iii. Flow control query report: “REP*:FLOW=OFF” (module uses

default flow control OFF)

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LM074 SPP with GAP Central Application v1.1

iv. Flow control set command: “AT*FLOW=ON” (Set module flow

control ON)

v. If the user is changing the flow control of device, after accepting

command with OK response, module shows report as

“REP*:FLOW_CHANGE= IN_Progress”

vi. Module will perform reboot in changed flow control mode

vii. If module is in flow control OFF mode and user gives command to

make the flow control OFF, then module will respond as OK but shall not perform reboot. Similar applies to flow control OFF setting.

4.3.5 “AT*CTS”\r\n:

i. Query command

ii. CTS query command: “AT*CTS=?”\r\n

iii. CTS query report: module will report the actual status of CTS line

e.g. “REP*:CTS=OFF” or “REP*:CTS=OFF”.

iv. CTS line cannot be set/reset.

v. This command is applicable for LM074 module and LM068

adapter.

4.3.6 “AT*DSR”\r\n:

i. Query command

ii. DSR query command: “AT*DSR=?”\r\n

iii. DSR query report: module will report the actual status of DSR line

e.g. “REP*:DSR=OFF” or “REP*:DSR=OFF”.

iv. DSR line cannot be set/reset.

v. This command is applicable for LM074 module and LM068

adapter.

4.3.7 “AT*RTS”\r\n:

i. Set only command

ii. RTS line set/reset command: “AT*RTS=ON”\r\n or

“AT*RTS=OFF”\r\n.

iii. RTS line cannot be queried. iv. This command is applicable for LM074 module and LM068

adapter.

4.3.8 “AT*DTR”\r\n:

i. Set only command

ii. DTR line set/reset command: “AT*DTR=ON”\r\n or

“AT*DTR=OFF”\r\n.

iii. DTR line cannot be queried. iv. This command is applicable for LM074 module and LM068

adapter.

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LM074 SPP with GAP Central Application v1.1

Sr No

Modem setting

Comment

None

Default setting

Local

LM068/LM074 uses RTS/CTS and DTR/DSR in loopback mode

Remote

When LM068/LM074 is connected to remote device, LM068/LM074 sends RTS /DTR line status to remote device and receives CTS/DSR line status from remote device

4.3.9 “AT*MODEM”\r\n:

i. Query and set command

ii. MODEM query command: “AT*MODEM=?”\r\n

iii. MODEM query report: “REP*:MODEM=NONE” (module uses

default MODEM settings as “none”) iv. MODEM set command: “AT*MODEM=LOCAL” or

“AT*MODEM=Remote”.

v. Refer below table for MODEM settings:

4.4 Bluetooth Security Settings commands:

4.4.1 “AT*PIN”\r\n

4.4.2 “AT*DPIN”\r\n

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vi. Modem settings LOCAL and REMOTE are followed when Flow-

control is off.

vii. MODEM command is applicable for LM074 module and LM068

adapter.

i. Query and set command

ii. PIN query command: “AT*PIN=?”\r\n

iii. PIN query report: “REP*:PIN=1234” (module uses default PIN as

1234)

iv. PIN set command: “AT*PIN=00112233” or “AT*PIN=Abcd”.

v. Maximum PIN length supported is as per BT2.1 standard i.e. 16

bytes. PIN string can be numeric only, alpha only, or alpha

numeric. vi. Examples for valid PIN set commands:

“AT*PIN=00112233445566778” or

“AT*PIN=001122aaBBccDDeef”

i. Query and set command

LM074 SPP with GAP Central Application v1.1

Sr No

IO type

LM951 / LM074 String for IOTYPE

LM951/LM074 IOTYPE set command

LM951/LM074 IOTYPE query response

No input output

NO_InOut

at*iotype=no_inout

REP*:IOTYPE=NO_InOut

Key Board only

KB_Only

at*iotype=Kb_OnLy

REP*:IOTYPE=KB_Only 3

Display only

Disp_Only

at*iotype=DISP_only

REP*:IOTYPE=Disp_Only

Display and confirmation for Yes / No

Disp_YN

at*iotype=DISP_YN

REP*:IOTYPE=Disp_YN

ii. Dynamic PIN query command: “AT*DPIN=?”\r\n

iii. Dynamic PIN query report: “REP*:DPIN=OFF” (module uses

default DPIN as off) iv. Dynamic PIN set enable or disable command: “AT*DPIN=ON” or

“AT*DPIN=off”.

v. When module has DPIN setting as OFF, Module uses a fixed PIN

provided default as 1234. vi. When module has DPIN setting as ON, module expects the

dynamic PIN from customer as per the MITM and IO-Type

settings.

vii. For further on BT2.1 pairing and MITM, DPIN, PASSKEY messages

refer “LM951/LM074 Pairing document”.

4.4.3 “AT*MITM”\r\n

i. Query and set command

ii. (Man IN The Middle) MITM query command: “AT*MITM=?”\r\n

iii. MITM query report: “REP*:MITM=OFF” (module uses default

MITM as off) iv. MITM set enable or disable command: “AT*MITM=ON” or

“AT*MITM=off”.

4.4.4 “AT*IOTYPE”\r\n

i. Query and set command

ii. (Input Output type for Dynamic PIN) IOTYPE query command:

“AT*IOTYPE=?”\r\n

iii. IOTYPE query report: “REP*:IOTYPE=NO_InOut” (module uses

default IOTYPE as “no input output”) iv. IOTYPE modify command: “AT*IOTYPE=KB_ONLY” or

“AT*IOTYPE=kB_OnLy”.

v. Following IO-types are supported:

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LM074 SPP with GAP Central Application v1.1

4.4.5 “AT*DEL”\r\n

i. Execution only command.

ii. User issues this command to delete the device from its paired list. iii. DEL command: “AT*del=00126f357215”\r\n iv. “OK” response will be provided if the string entered has valid BT

address. Module deletes the device from its pairing list.

v. “Err” response will be provided if invalid BT address, invalid length

of address is provided.

vi. If device is deleted form the pairing list, Module will follow pairing

procedure before getting connected with the device.

4.4.6 “AT*PASSKEY”\r\n

i. Execution only command.

ii. When the module has DPIN=ON, MITM=ON and IOTYPE as

Keyboard Only, in pairing procedure module gives indication

“IND*:PASSK=?”.

iii. User shall provide the pass key in following format:

“AT*PASSKEY=1234”\r\n .

iv. Any integer within the range uint32 is considered as valid Passkey.

4.4.7 “AT*PASSCFM”\r\n

i. Execution only command.

ii. When the module has DPIN=ON, MITM=ON and IOTYPE as

DISPLAY confirmation Yes/No, in pairing procedure module gives indication “IND*:PASSK=xxxxxx”.

iii. User shall provide the confirmation for pass key in following

format: “at*passcfm=00126f357215,Yes”\r\n or

“at*passcfm=00126f357215,no”\r\n

4.4.8 “AT*STOPPAIR”\r\n

i. Execution only command.

ii. Used to stop the pairing procedure for a device. iii.

Once the module starts pairing procedure, the stack completes the procedure within maximum 90 seconds. User can stop the pairing procedure within this time.

iv. Issue command to stop the pairing procedure with the BT address

of the peer device e.g. “AT*stoppair=00126f357215”

4.4.9 “AT*PAIRLIST”\r\n

i. Query only command.

ii. Pairlist query command: “AT*PAIRLIST=?”\r\n

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LM074 SPP with GAP Central Application v1.1

Sr No

SPP Role

LM951/LM074 Role set command

LM951/LM074 Role query response

Dual role ( SPP Slave and SPP master role )

At*role=dual

REP*:SPPRole=DUAL

SPP Slave Only

At*role=slave

REP*:SPPRole=SLAVE

iii. Pairlist report may be multiple line if module is paired with more

than one device. Paired devices report is shown in following format

“REP*:PAIRLIST=00126f357201, REP*:PAIRLIST=00126f357215, REP*:PAIRLIST=END”

iv. Pairlist report can be multiple line, to indicate end of the report

“REP*:PAIRLIST=END” is displayed at end.

4.5 SPP Related commands:

4.5.1 “AT*FIND”\r\n

i. Execution only command.

ii. Used to start the discovery of Bluetooth devices nearby. iii. Start discovery command format is “AT*FIND=ON”\r\n iv. Stop discovery of Bluetooth devices by command

“AT*FIND=Off”\r\n.

v. Module shows discovered devices with their name and addresses.

Each device is reported as soon as it is discovered.

vi. Report for each device is sent with new line. To indicate the end

of the discovery report, “REP*:FIND=END” message is shown.

vii. If module did not get reply to nam query of remote device it will

display NULL in name string (e.g. row 3 in below report).

viii. Example report for discovery:

“at*find=onat*find=on OK REP*:FIND=Start.. = 1 0002-5b-00a5a5 Serial Adapter = 2 0026-4a-a19172 LML11 = 3 442a-60-da6c58 NULL = 4 4c49-e3-68b246 Redminote REP*:FIND_END= 4 devices found.”

4.5.2 “AT*ROLE”\r\n

i. Query and Set command.

ii. Query command = “AT*ROLE=?”\r\n iii. Report for SPP role query is “REP*:SPPRole=SLAVE”\r\n . Default

role is Slave mode supporting SPP incoming connections.

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LM074 SPP with GAP Central Application v1.1

SPP Master only

At*role=master

REP*:SPPRole=MASTER

iv. When the module is in Dual mode, it can accept incoming SPP

connection as well as initiate outgoing SPP connection whereas module cannot accept or initiate new connection when it is already connected to any remote device. E.g. if module has established an outgoing connection, then after terminating the outgoing connection it can accept incoming connection.

v. In slave-only role

1. BOND=Valid-BD-address. (e.g. BOND=0012-6f-

357215) x Module will accept connection request only from bonded

device. Connection requests from other devices will be rejected by module.

2. BOND=0000-00-000000. x Module will accept connection request from ay device.

vi. In master-only role, Refer ACON and BOND command for more

details.

vii. In any role (dual, Slave only or Master only role) module can

support only one connection at an instance.

4.5.3 “AT*ACON”\r\n

i. Query and set command.

ii. This setting is applicable for Master only role. iii. Auto connect query command: “AT*ACON=?”\r\n iv. Auto connect query report: “REP*:ACON=OFF”

v. Command to set ACON as ON is “AT*ACON=ON”\r\n vi. When the module is in Master-only role and ACON setting is ON,

1. BOND=Valid-BD-address. (e.g. BOND=0012-6f-

357215) x If device has valid address for BOND, it keeps issuing

connection request to that device till the connection is established.

2. BOND=0000-00-000000. x If device has BOND address as Zero, it will start

discovery of nearby Bluetooth devices and issues connection request to first found device.

vii. When module is in Master-only role and ACON setting is OFF,

module will wait for AT command from user to initiate the connection request (module will not accept any incoming connection request).

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LM074 SPP with GAP Central Application v1.1

4.5.4 “AT*BOND”\r\n

i. Query and set command.

ii. Set command: “AT*BOND=00126f357215”\r\n. Device will

establish connection only with remote device having BD address as 00126f357215.

iii. Set command: “AT*BOND=000000000000”\r\n. Device will

establish connection with any device.

iv.

v. This setting is applicable for Master-only, slave-only role. When

Bond Address setting holds a valid Bluetooth address then LM068/LM074/LM074 will establish connection only with that device.

vi. LM068/LM074/LM074 can be paired with maximum 8 devices and

stores the device addresses in its permanent memory (this is called as TDL-Trusted_Devices_List or PDL-Paired_Devices_List) whereas it can be bonded to only one device at a time whose address is mentioned in BOND command setting.

vii. Bond device address query command: “AT*BOND=?”\r\n.

viii. Default settings is: “REP*:BOND=0000-00-000000”.

ix. Setting for default bond device address is Zero i.e. device is not

bonded to any remote device and can accept or issue connection request to any remote device.

x. Command to set ACON as ON is “AT*ACON=ON”\r\n.

xi. When the module is in Master only role and ACON setting is ON,

module performs the discovery of nearby devices and tries to connect with the first found device for SPP connection.

4.5.5 “AT*CONN”\r\n

i. Execution only command.

ii. Supported in SPP Master-only and Dual mode.

iii. If module is MASTER role and ACON setting is ON, the module will

always respond to this command as “ERR” as it only issues a connection request to BOND device, or it performs discovery on its own and attempts to connect to first device found.

iv. User can start to initiate outgoing SPP connection.

v. Outgoing connection command: “AT*conn=00126f357215”\r\n

vi. “OK” response will be provided if the string entered has valid BT

address, module is not connected to any device.

vii. “Err” response will be provided if invalid BT address, invalid length

of address is provided or if the module is already in connected state.

viii. After module gives OK response to at+conn command, it starts

the connection procedure. Result of connection procedure is indicated as indication message.

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LM074 SPP with GAP Central Application v1.1

1. “IND*:CONN_FAILURE=00126f357215” message is shown to indicate the failure in connection with BD address 00126f-357215.

2. “IND*:CONNECTED=00126f357215” message is shown to indicate the SPP connection is successfully established and the devices are in connected state.

3. Once the devices are connected, LM951/LM074 is in SPP- connected-online-data mode. Every string entered by host on UART is treated as data and is transmitted to connected device.

4. User can come out of this mode by entering the Escape sequence.

4.5.6 Escape sequence “+++”

i. Execution only command/sequence.

ii. Supported only in SPP-connected-online-data mode.

iii. User issues this command to enter in SPP-connected-online-

command mode.

iv. If the user issues escape sequence in SPP-connected-online-data

when LED D10 is Blinking, OK response is given by module and module enters in SPP-connected-online-command mode.

v. Once the module enters in SPP-connected-online-command mode,

any strings entered on UART are considered as AT commands and are processed by module (still the module is in connected state).

vi. In SPP-connected-online-command mode, users can query/update

module settings and start the disconnection by issuing at*drop command.

4.5.7 “AT*AUTO”\r\n

i. Execution only command/sequence.

ii. Supported only in SPP-connected-online-command mode.

iii. User issues this command to enter back in SPP-connected-

online-data mode.

iv. After entering in SPP-connected-online-data mode, any data

entered on UART is transmitted to the remote device over Bluetooth.

4.5.8 “AT*DROP”\r\n

i. Execution only command.

ii. Supported in all SPP roles (dual, master-only or slave-only).

iii. User issues this command in SPP-connected-online-command

mode to terminate the existing SPP connection (applicable for existing incoming or outgoing SPP connection).

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LM074 SPP with GAP Central Application v1.1

iv. connection termination command: e.g.

“AT*DROP=00126f357215”\r\n

v. “OK” response will be provided if the string entered has valid BT

address and module is connected to the device with entered BT address and module is in online-command mode.

vi. “Err” response will be provided if invalid BT address, invalid length

of address is provided, module is not connected to any device.

vii. AT*drop command causes the indication message to indicate the

devices are successfully disconnected.

viii. “IND*:DISCONNECTED=00126f357215” indication message is

shown to indicate the module is disconnected from the device with BT address 0012-6f-357215.

4.6 Firmware Upgrade commands:

4.6.1 “AT*UPGRADE”\r\n

i. Execution only command.

ii. Supported in all SPP roles (dual, master-only or slave-only).

iii. The module should not be connected to BLE or any Bluetooth

device before starting the procedure.

iv. User issues this command in SPP-connected-online-command

mode to perform the OTA-firmware-upgrade.

v. User shall enter this command with password provided for

firmware upgrade. If the password is correct, then module issues OK response and is ready for performing firmware upgrade.

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LM074 SPP with GAP Central Application v1.1

5. LM074 Over The Air Firmware Upgrade Procedure

This section describes the procedure to perform an over the air firmware upgrade for the LM074 module.

Users can use serial terminals like Hercules, HyperTerminal, Tera term or Putty etc. for serial communication with LM074 module.

In this document, the term “new image” refers to the firmware image to which the LM074 will be upgraded to.

The LM074 receives the new image from a peer device which is connected to itself with Bluetooth.

The LM074 can receive new images over SPP profile only. The module does not support other Bluetooth profiles to receive a new image.

5.1 Pre-requisites for Firmware upgrade:

5.1.1 New Firmware image:

i. New Firmware image is provided as “xxxxxxx.bin” file to user.

ii. User shall store this image on PC/Laptop/device used to connect

to the LM074 module for OTA upgrade.

iii. LM074 module can be upgraded with the image provided by LM

Technologies only.

5.1.2 Peer Bluetooth device requirements:

i. Peer Bluetooth device should support sending file over SPP profile

(some mobile applications may not support this).

ii. LM technologies has tested LM048/LM058 or LM074 module to

send the new image with Hercules utility from windows PC. iii. Peer device should support pairing requirements. iv. LM074 will connect only with Paired device hence receives image

only from paired device.

5.1.3 Pairing and Authentication of Peer device:

i. LM074 can pair with remote device with fixed PIN.

ii. LM074 can pair with remote device with dynamic PIN and MITM

protection enabled. iii. For detailed pairing procedure of LM074 with AT commands,

please refer document “LM074 module Pairing procedure

R1.0.pdf”

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LM074 SPP with GAP Central Application v1.1

5.1.4 LM074 requirements:

i. LM074 can be SPP master (initiate connection with remote device)

or SPP Slave (Accept connection request from remote device).

5.2 Firmware upgrade procedure Flow chart:

The flow chart below illustrates the firmware upgrade procedure, highlighting messages when the upgrade operation is successful.

The comments show the failure points as FP1 to FP5. The cause of failure points and actions to overcome them are discussed in the subsequent section.

Note: During the upgrade procedure, after the module displays the message “Ready to receive OTA file”, if the user fails to send the image to the LM074 module, the module/user cannot terminate the OTA mode. The user has to provide power-on/off cycle to come out of OTA upgrade mode. Another way to come out of this mode; the remote connected device has to send at-least 200 bytes of data. The module will treat this data as an upgrade image but due to failure it will reboot itself with existing firmware.

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LM074 SPP with GAP Central Application v1.1

Figure 1: Firmware Upgrade Flowchart

Note: The firmware upgrade password is dependent on the current firmware version.

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LM074 SPP with GAP Central Application v1.1

5.3 Possible Failure points and corrective actions

The following section describes the possible failure points while performing an Over the Air firmware upgrade. It also covers possible reasons for errors what a user can do to correct them.

5.3.1 Failure point 1:

i. After entering the escape sequence “+++”, the module should

respond as OK and enter in Online-connected-command-mode.

ii. If module does not respond as “OK” (it will not reply as “ERR” in

this state), module is still in “online-connected-data-mode” and

sends data to remote device. iii. PIO-xx is toggled or LED D10 starts blinking to show the module is

ready to accept the escape sequence. iv. User should enter escape sequence immediately after the D10 led

starts blinking.

v. If module does not reply as “OK”, user should wait till module is

ready to receive next escape sequence. vi. Module is ready to process firmware upgrade even if there are

multiple attempts of failure to enter in Online-connected-

command-mode.

vii. User cannot process further steps if module does not enter in

online-connected-command-mode.

Note: If the Current firmware on the LM074 module is a Bridge application or GAP-Central-Only, then after SPP connection the LM074 enters into Command mode. Then there is no need to enter the Escape sequence. The user can directly issue the “AT*upgrade” command.

5.3.2 Failure point 2:

i. Once the module enters into the Online-connected-command-

mode, the user should provide the firmware upgrade password

through AT commands.

ii. If the user provides the correct firmware upgrade password, the

module responds to the command as “OK” and displays the

message “Ready to receive OTA file” iii. The module replies as “ERR”

a. If the user enters a wrong password for upgrade command,

module responds as ERR.

b. Firmware upgrade password is dependent on current

firmware version of the module.

c. E.g. if the current firmware version on the module is “1.50”,

the firmware upgrade password will be “AT*upgrade=LMUPDATEV150”.

d. In the “AT*upgrade” command the string after “=” is case

sensitive and should be entered in all uppercase (for letters).

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LM074 SPP with GAP Central Application v1.1

e. If the module replies as “ERR”, the user should try entering

the correct password and try to get the message “Ready to receive OTA file”.

f. The module can process successfully even though it already

had more than one failure attempt while getting “Ready to receive OTA file” message.

5.3.3 Failure point 3:

i. Once the module enters in Online-connected-command-mode, the

user should provide the firmware upgrade password through AT

command.

ii. If the user provides the correct firmware upgrade password, the

module responds to the command with “OK”. iii. After displaying the OK response, the module displays the

message “Ready to receive OTA file” if it is in the state to receive

the upgrade image. iv. Module replies as “State Err”

a. If the firmware upgrade password is correct but module is

not in state to perform the upgrade procedure, the module will respond as “State err” to the “AT*upgrade” command.

b. The module will display “State err” message if it is not

connected to a remote device or it has lost the current connection.

c. If module replies as “State err”, the user cannot proceed to

the firmware upgrade procedure and should check for the BT connection of LM074 with peer device.

d. In this case, the user shall start the upgrade procedure from

the beginning.

e. Refer to the image below:

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LM074 SPP with GAP Central Application v1.1

Figure 2: UART messages when the module is not connected to the peer device

5.3.4 Failure point 4:

i. After the module shows the message “Ready to receive OTA file”,

it is ready to receive the upgrade image.

ii. After the peer device begins sending the file, the module opens

internal memory partition2 or partition3 to write this image iii. The message “PTN2”/”PTN3” indicates that the module is writing

the file to partition2/partition3. iv. This message should appear one or two seconds after the peer

starts sending the file.

v. If the module does not show this message, but the peer device

indicates that the file has been sent, an error has occurred. vi. In this case the user should power the module on and off or reset

the module with the “AT*reset=1” command and try the

procedure from start again.

vii. Refer to the image below

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LM074 SPP with GAP Central Application v1.1

Figure 3: UART messages when the module opens a partition to write a new image

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LM074 SPP with GAP Central Application v1.1

5.3.5

Failure point 5:

i. The message “PTN2”/”PTN3” indicates that the module is writing a

file to partition2/partition3, module is receiving the file and writing

it to the partition.

ii. After the peer device shows that it has successfully sent the file,

LM074 will close the partition. iii. After the partition is closed, the message “Sign_OK” indicates that

the module has received Signature. iv. The message “Sink_Closed” indicates that the module has closed

the partition after receiving the random string.

v. After the partition is closed and if the upgrade procedure is

completed successfully, the module shows the message

“V_PASS_2” / “V_PASS_3”. vi. If module shows the “failed-CRC” message:

a. If CRC of the received image is not matching to the CRC

mentioned in the image, the module shows a “Failed-CRC” message.

b. This may be because of disturbances/interferences in

wireless transmission. If so the user should repeat the procedure from beginning.

c. The module restarts itself with a warm reset and starts

executing the existing image.

d. Refer to the image below:

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LM074 SPP with GAP Central Application v1.1

Figure 4: UART messages when the CRC of the received image does not match

vii. If the module shows “failed-Sign” message:

a. If module shows the “failed-Sign” message, it indicates that

the signature of module firmware is different than the signature of the new image.

b. This indicates that the firmware upgrade procedure has been

followed correctly but there is error in new image provided for the firmware upgrade.

c. If the image is not suitable for performing a firmware

upgrade the user should contact LM technologies.

d. The module restarts itself with a warm reset and starts

executing the existing image.

e. Refer to the image below:

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LM074 SPP with GAP Central Application v1.1

Figure 5: UART messages showing a failure in image verification

5.3.5 Successful firmware Upgrade:

i. The image below depicts the messages shown by the module

during a successful firmware upgrade procedure

ii. After showing message “V_Pass_2” or “V_Pass_3”, the module

performs warm reset and starts executing the new image. iii. In the image below, the message “Entering Message Loop”

indicates that the device has performed warm reboot. The

message “GATT Initialised” indicates that the new image has

GATT is enabled for BLE connectivity.

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LM074 SPP with GAP Central Application v1.1

Figure 6: UART messages showing successful firmware upgrade

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LM074 SPP with GAP Central Application v1.1

6. Simple Secure Pairing between LM074 and remote device

This section describes the indication messages given by the LM074 module during the pairing procedure. It also covers the AT commands that a user will need to provide as per the settings of DPIN, MITM and IOTYPE.``

The LM074 uses BT2.1 security supporting the dynamic PIN, but is also compatible with BT2.0 devices which shares fixed PIN during the pairing procedure.

6.1 Pairing of LM074(BT2.1) with BT2.0 devices

Here the BT2.0 device is treated as LM Technologies’ LM048 device, with firmware version 6.57. When the LM074 has DPIN as DPIN=OFF, it is compatible with BT2.0 devices. When DPIN=OFF, the module does not care about MITM, IOTYPE settings. When DPIN is OFF, module uses PIN during the pairing procedure with remote devices. Default PIN is 1234, users can change this to numeric only, Alpha only or alphanumeric. As per Bluetooth standards, maximum of 16 characters are allowed in PIN setting.

6.1.1 If LM074 has setting DPIN=OFF

i. When the pairing procedure is started on the LM074, it will show

the indication message with the BD-Address of remote device e.g “IND*:PAIR=00126f357215”.

ii. The user shall provide accept/reject response to this indication as

“AT*PAIR=00126f357215,accept” or

“AT*PAIR=00126f357215,reject”. iii. LM074 uses its fixed PIN. iv. If the fixed PIN of LM074 is same as the other device pairing is

successful.

v. After completing the pairing procedure, the LM074 indicates the

status of pairing to user e.g. “IND*:PAIR=OK,00126f357215” or

“IND*:PAIR=FAIL,00126f357215” . vi. If the fixed PIN of LM074 is not same as other device pairing fails.

6.2 Pairing of LM074 (BT2.1) with BT2.1 devices

Here the BT2.0 device is treated as LM Technologies’ LM048 device with firmware version 6.19. The passkey used during the pairing procedure is dependent on the IO-type setting on the LM074.

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LM074 SPP with GAP Central Application v1.1

If IO-type is keyboard only, the LM074 will expect the passkey from the user and use it internally for the pairing procedure.

When the IO-type is display only, the LM074 will display the passkey and the user should use the same passkey on the remote device to complete the pairing procedure.

When IO-type is Display with yes/no confirmation, the LM074 displays passkey and expects confirmation from the user whether the passkey for remote device is the same.

When the IO-type is NO-INOUT i.e. no input no output then it depends on the peer device whether the pairing will be successful or not. If the IOtype is No-input-no-output, MITM should be off otherwise the LM074 will never be able to pair with a remote device.

If the LM074 and remote device has IO-type as No-input-no-output and MITM as off then devices may pair successfully by “just works” pairing type.

6.2.1 LM074 has settings DPIN=on, MITM=on, IOtype=Keyboard-only

i. After the LM074 indicates Pairing as “IND*:PAIR,00126f357215”

and the user accepts the Pairing request with “AT*PAIR=00126f357215, accept”, the LM074 starts the pairing procedure.

ii. IO-type as Keyboard only indicates that user can provide Passkey

for pairing using AT commands.

iii. The bluetooth stack will use this passkey for completing the

pairing procedure with the remote device.

iv. During the pairing procedure, the LM074 displays the message

“IND*:PASSK=?”. This indicates that the LM074 requires a Passkey from the user.

v. The user should respond to this with “at*passkey=1234”. i.e. the

passkey for the remote device is 1234. It can be any integer in range of 32bit value.

vi. After completing the pairing procedure, the LM074 indicates the

status of pairing to the user e.g. “IND*:PAIR=OK,00126f357215” or “IND*:PAIR=FAIL,00126f357215” .

6.2.2 LM074 has settings DPIN=on, MITM=on, IOtype=display only

i. After the LM074 shows indication of Pairing

“IND*:PAIR,00126f357215” and user accepts the Pairing request

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LM074 SPP with GAP Central Application v1.1

with “AT*PAIR=00126f357215, accept”, LM074 starts pairing procedure.

ii. When the LM074 starts the pairing procedure with a remote

device and has IO-capability as Display only, LM074 shows the Passkey for remote device as message “IND*:PASSKEY=311303” here number 311303 is for reference only and should vary for every device.

iii. IO-type as Display only indicates that the Passkey generated by

the Bluetooth stack for pairing is only displayed by the LM074.

iv. The user should ensure that the other device uses the passkey

provided by the LM074 module in above indication.

v. If the remote device uses the passkey displayed by the LM074

then the pairing procedure should be completed successfully.

vi. After the pairing procedure is completed, the LM074 indicates this

as “IND*:PAIR=OK,00126f357215” . 00126f357215 is the reference BD address and LM074 will show the remote devices BD-Address.

6.2.3 LM074 has settings DPIN=on, MITM=on, IOtype=Display Y/N

i. After the LM074 indicates Pairing as “IND*:PAIR,00126f357215”

and the user accepts the pairing request with “AT*PAIR=00126f357215, accept”, the LM074 starts the pairing procedure.

ii. When the LM074 starts the Pairing procedure with the remote

device and has IO-capability as Display_YN i.e. Display passkey and Confirmation is required as Yes or No, LM074 shows the Passkey for remote device and expects the confirmation from user as yes or No.

iii. The passkey is displayed by the LM074 module as

“IND*:PASSKEY=756830”.

iv. User shall provide confirmation with the AT command as

“at*passcfm=00126f357215,Yes” or “at*passcfm=00126f357215,No”.

v. The remote device should be set as IO-type as display-only or

display-YN otherwise pairing will not be possible.

6.2.4 LM074 has settings DPIN=on, MITM=on, IO-type=noInput-no-output

i. Pairing with the remote device may or may not be successful and

depends on MITM and IO-type settings of remote device.

ii. If the remote device also has the same settings, then pairing may

be successful otherwise the pairing might fail.

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6.2.5 LM074 has settings DPIN=on, MITM=off, IO-type=noInput-no-output

i. Pairing with the remote device might be successful if the remote

device also has DPIN=on, MITM=off and IO-type as no one.

ii. If the remote device has MITM=on or IO type other than no input

no output, the LM074 cannot pair with that device.

7. LED Indication

7.1 Power on LED sequence

1. All LEDs blink fast during power on for 3 seconds. User can notice all LEDs blinking approximately 6 to 7 times.

2. The module shows power on LED sequence after AT*Reset=1 and AT*Reset=2 commands.

LM074 SPP with GAP Central Application v1.1

7.2 LED0

1. LED0 (RED LED on LM068) is constantly ON to indicate that the module/adapter is powered and active for AT commands, Bluetooth discovery, audio functionality.

2. If LED0 is not ON, module/adapter may not be powered correctly or not initialised.

3. The state of LED0 is irrespective of Bluetooth connection or pairing state.

7.3 LED1

1. LED1 (Yellow LED on adapter) indicates the data transfer in the SPP connected state.

2. When the module/adapter is not connected to the remote SPP device, LED1 should be OFF.

3. When the module/adapter connects to a remote SPP device, LED1 is ON for the duration of the module/adapter receiving data or sending data to the remote device.

4. LED1 should be off when there is no active data transfer on the Bluetooth connection.

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LM074 SPP with GAP Central Application v1.1

7.4 LED2

SPP Connected state:

1. LED2 (Blue LED) shall be constantly ON when the module/adapter is connected to the remote device over a SPP connection.

2. LED2 will be constantly ON when it is connected to a remote device while its role is slave or master.

Slave-mode:

1. When the module/adapter is in slave mode, LED2 will keep blinking fast until the module/adapter enters into Connected state or Pairing mode.

Master-mode:

1. When the module/adapter is not connected to a remote device and is in master mode, LED2 will blink slowly until the module/adapter enters into Pairing state or Connected state.

7.5 Pairing State

1. When the module/adapter is in pairing mode, LED-1 and LED2 will keep blinking fast until pairing is completed.

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SSP

Simple Secure Pairing

Bluetooth

BLE

Bluetooth low energy

BD-Address

Bluetooth address of device

BT2.0

Bluetooth 2.0 stack

BT2.1

Bluetooth 2.1 stack

MITM

Man In The Middle protection

IOTYPE

Input Output Type (IO capability of device)

DPIN

Dynamic PIN

Personal Identification Number

Characteristic

Bit field for characteristic

Indication on LM074

Description

broadcast

0x01

“Bd”

Broadcasts of the Characteristic Value User cannot read or write on this characteristic

read

0x02

"Rd "

Reads of the Characteristic Value. User can read this characteristic with RDCHARVAL command

write_cmd

0x04

"Wr_cmd "

Writes of the Characteristic Value without response. User can write on this characteristic with AT*WRWORESP command

8. Appendix

8.1 Abbreviations

LM074 SPP with GAP Central Application v1.1

8.2 BLE Peripheral characteristics

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LM074 SPP with GAP Central Application v1.1

write

0x08

"Wr_req "

Writes of the Characteristic Value with response. User can write on this characteristic with AT*WRCHARVAL command

notify

0x10

"CCFG "

Client configuration flag for notification enable If user enables this flag, remote device shows notification

indicate

0x20

"Indi "

Indications of a Characteristic Value with acknowledgement. LM074

will show indication message if receives data form this characteristic

write_sig

0x40

"Wr_signed "

Signed writes to the Characteristic Value using Signed Write Command. User can write on this characteristic with AT*SIWRWORESP command

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8.3 GATT UUID type

1. All UUID values are in Hex.

2. 16-bit Attribute UUID is represented as “1801”

3. 32-bit UUID is represented as “32005b32”

4. All UUIDs are Big Endian, i.e. for example 128-bit UUID 001122334455-6677-8899-aabbccddeeff

LM074 SPP with GAP Central Application v1.1

Sr No

Error code

Error description

0x0

gatt_status_success

0x1

gatt_status_invalid_handle

0x2

gatt_status_read_not_permitted

0x3

gatt_status_write_not_permitted

0x4

gatt_status_invalid_pdu

0x5

gatt_status_insufficient_authentication

0x6

gatt_status_request_not_supported

0x7

gatt_status_invalid_offset

0x8

gatt_status_insufficient_authorization

0x9

gatt_status_prepare_queue_full

0xa

gatt_status_attr_not_found

0xb

gatt_status_not_long

0xc

gatt_status_insufficient_encr_key_size

0xd

gatt_status_invalid_length

0xe

gatt_status_unlikely_error

0xf

gatt_status_insufficient_encryption

0x10

gatt_status_unsupported_group_type

0x11

gatt_status_insufficient_resources

0x12

gatt_status_application_error

0x13

gatt_status_initialising

5. uuid[0] = 0x00112233, uuid[1] = 0x44556677, uuid[2] = 0x8899aabb, and uuid[3] = 0xccddeeff.

6. If the service-UUID is 128-bit, it is completely mentioned in the report of FindServ e.g. “00005500-d102-11e1-9b23-00025b00a5a5”

7. If the characteristic has 128-bit UUID then only first 32 bits are shown e.g.

8. “00005501” is shown whereas the actual 128-bit UUID is “00005501D10211E1-9B230002-5B00a5a5” here the remaining bits are same as that of the 128-bit Service UUID shown above.

8.4 GATT_Status_code

The BLE stack outputs an error if the required operation fails. The table below lists the possible error codes with a description.

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LM074 SPP with GAP Central Application v1.1

Sr No

Error code

Error description

0x14

gatt_status_failure

0x15

gatt_status_att_reg_failure

0x16

gatt_status_att_db_failure

0x17

gatt_status_max_connections

0x18

gatt_status_abnornal_disconnection

0x19

gatt_status_link_loss

0x1a

gatt_status_mtu_already_exchanged

0x1b

gatt_status_value_mismatch

0x1c

gatt_status_rej_psm

0x1d

gatt_status_rej_security

0x1e

gatt_status_key_missing

0x1f

gatt_status_connection_timeout

0x20

gatt_status_retrying

0x21

gatt_status_peer_aborted

0x73

gatt_status_device_not_found

0x74

gatt_status_sign_failed

0x75

gatt_status_busy

0x76

gatt_status_timeout

0x77

gatt_status_invalid_mtu

0x78

gatt_status_invalid_uuid

0x79

gatt_status_success_more

0x7a

gatt_status_success_sent

0x7b

gatt_status_invalid_cid

0x7c

gatt_status_invalid_db

0x7d

gatt_status_db_full

0x7e

gatt_status_invalid_phandle

0x7f

gatt_status_invalid_permissions

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Sr No

Service

UUID

Generic Access

0x1800

Alert Notification Service

0x1811

Automation IO

0x1815

Battery Service

0x180F

Blood Pressure

0x1810

Body Composition

0x181B

Bond Management Service

0x181E

Continuous Glucose Monitoring

0x181F

Current Time Service

0x1805

Cycling Power

0x1818

Cycling Speed and Cadence

0x1816

Device Information

0x180A

Environmental Sensing

0x181A

Fitness Machine

0x1826

Generic Attribute

0x1801

Glucose

0x1808

Health Thermometer

0x1809

Heart Rate

0x180D

HTTP Proxy

0x1823

Human Interface Device

0x1812

Immediate Alert

0x1802

Indoor Positioning

0x1821

Internet Protocol Support Service

0x1820

Link Loss

0x1803

Location and Navigation

0x1819

Mesh Provisioning Service

0x1827

Mesh Proxy Service

0x1828

Next DST Change Service

0x1807

Object Transfer Service

0x1825

Phone Alert Status Service

0x180E

Pulse Oximeter Service

0x1822

Reference Time Update Service

0x1806

Running Speed and Cadence

0x1814

Scan Parameters

0x1813

Transport Discovery

0x1824

Tx Power

0x1804

User Data

0x181C

Weight Scale

0x181D

8.5 BLE Service UUIDs

BLE Service UUIDs for reference only.

LM074 SPP with GAP Central Application v1.1

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2.2 List of applicable FCC rules

FCC Part 15.247

2.3 Specific operational use conditions

This product is a Dual-modular transmitter policy independent of any host. Not applicable.

2.4 Limited module procedures

This product is a S Dual-modular transmitter. It is not a limited module. Not applicable.

2.5 Trace antenna designs

This product has an Integral antenna. Not applicable.

2.6 RF exposure considerations

This equipment complies with the FCC RF radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with a minimum distance of 20cm between the radiator and any part of your body.

2.7 Antennas

This product has an Integral antenna. Not applicable.

2.8 Label and compliance information

Remind end customers to add "Contain FCC ID: VVXLM074"

2.9 Information on test modes and additional testing

requirements

Contact LM Technologies Ltd. will provide stand-alone modular transmitter test mode. Additional testing and certification may be necessary when multiple modules are used in a host.

2.10 Additional testing, Part 15 Subpart B disclaimer

To ensure compliance with all non-transmitter functions the host manufacturer is responsible for ensuring compliance with the modu le(s) installed and fully operational. For example, if a host was previously authorized as an unintentional radiator under the Supplier’s Declaration of Conformity procedure without a transmitter certified module and a module is added, the host manufacturer is responsible for ensuring that the after the module is installed and operational the host continues to be compliant with the Part 15B unintentional radiator requirements. Since this may depend on the details of how the module is integrated with the host, LM Technologies Ltd. shall provide guidance to the host manufacturer for compliance with the Part 15B requirements.

FCC Warning

This device complies with Part 15 of the FCC Rules. Operation is subject to the following two

conditions:

(1) This device may not cause harmful interference, and (2) this device must accept any

interference received, including interference that may cause undesired operation.

NOTE 1: Any changes or modifications to this unit not expressly approved by the party

responsible for compliance could void the user's authority to operate the equipment.

FCC Radiation Exposure Statement:

This equipment complies with FCC radiation exposure limits set forth for an uncontrolled

environment. End users must follow the specific operating instructions for satisfying RF exposure

compliance.

This module certified that complies with RF exposure requirement under mobile or fixed

condition, this module is to be installed only in mobile or fixed applications.

A mobile device is defined as a transmitting device designed to be used in other than fixed

locations and to generally be used in such a way that a separation distance of at least 20

centimeters is normally maintained between the transmitter's radiating structure(s) and the body of

the user or nearby persons. Transmitting devices designed to be used by consumers or workers that

can be easily re-located, such as wireless devices associated with a personal computer, are

considered to be mobile devices if they meet the 20 centimeter separation requirement.

A fixed device is defined as a device is physically secured at one location and is not able to be

easily moved to another location.

Note 2: Any modifications made to the module will void the Grant of Certification, this module is

limited to OEM installation only and must not be sold to end-users, end-user has no manual

instructions to remove or install the device, only software or operating procedure shall be placed

in the end-user operating manual of final products.

Note 3: Additional testing and certification may be necessary when multiple modules are used.

Note 4: The module may be operated only with the antenna with which it is authorized. Any

antenna that is of the same type and of equal or less directional gain as an antenna that is

authorized with the intentional radiator may be marketed with, and used with, that intentional

radiator.

Note 5: To ensure compliance with all non-transmitter functions the host manufacturer is

responsible for ensuring compliance with the module(s) installed and fully operational. For

example, if a host was previously authorized as an unintentional radiator under the Supplier’s

Declaration of Conformity procedure without a transmitter certified module and a module is added,

the host manufacturer is responsible for ensuring that the after the module is installed and

operational the host continues to be compliant with the Part 15B unintentional radiator

requirements. Since this may depend on the details of how the module is integrated with the host,

LM Technologies Ltd. shall provide guidance to the host manufacturer for compliance with the

Part 15B requirements.

Note 6: FCC ID label on the final system must be labeled with “Contains FCC ID: VVXLM074”

or “Contains transmitter module FCC ID: VVXLM074”.

Note 7: For all products market in US, OEM has to limit the operation channels in CH1 to CH11

for 2.4G band by supplied firmware programming tool. OEM shall not supply any tool or info to

the end-user regarding to Regulatory Domain change.

IC WARNING

This device contains licence-exempt transmitter(s) that comply with Innovation, Science and

Economic Development Canada’s licence-exempt RSS(s). Operation is subject to the following

two conditions:

(1) This device may not cause interference.

(2) This device must accept any interference, including interference that may cause undesired

operation of the device.

L’émetteur/récepteur exempt de licence contenu dans le présent appareil est conforme aux CNR

d’Innovation, Sciences et Développement économique Canada applicables aux appareils radio

exempts de licence. L’exploitation est autorisée aux deux conditions suivantes:

1. L’appareil ne doit pas produire de brouillage;

2. L’appareil doit accepter tout brouillage radioélectrique subi, même si le brouillage est

susceptible d’en compromettre le fonctionnement.

This radio transmitter [enter the device’s ISED certification number] has been approved by Innovation, Science and Economic Development Canada to operate with the antenna types listed below, with the maximum permi ssible gain indicated. Antenna ty pes not included in this list that have a gain greater than the maximum gain indicated for any type listed are strictly prohibited for use with this device.

No. Antenna Type Gain Impedance

1 External uniqueness Antenna 2dBi 50ohm

1 Internal uniqueness Antenna 2dBi 50ohm

IC Radiation Exposure Statement:

This device and its antenna(s) must not be co-located with any other transmitters except in

accordance with IC multi-transmitter product procedures. Referring to the multi-transmitter policy,

multiple-transmitter(s) and module(s) can be operated simultaneously without reassessment

permissive change.

Cet appareil et son antenne (s) ne doit pas être co-localisés ou fonctionnement en association avec

une autre antenne ou transmetteur.

This equipment complies with IC RSS-102 radiation exposure limits set forth for an uncontrolled

environment. This equipment should be installed and operated with minimum distance 20cm

between the radiator & your body.

Cet équipement est conforme aux limites d'exposition aux rayonnements IC établies pour un

environnement non contrôlé. Cet équipement doit être installé et utilisé avec un minimum de

20cm de distance entre la source de rayonnement et votre corps.

This module is limited to OEM installation only and must not be sold to end-users, end-user has

no manual instructions to remove or install the device, only software or operating procedure shall

be placed in the end-user operating manual of final products. Additional testing and certification

may be necessary when multiple modules are used.

Any changes or modifications not expressly approved by the manufacturer could void the user's

authority to operate this equipment.

The final end product must be labeled in a visible area with the following " Contains IC:

10531A-LM074 ".

LM Technologies LM074 Users Manual

Specifications and Main Features

Frequently Asked Questions

User Manual