Microhard Systems 00P3 User Manual
Operating Manual
And Professional Installation Guide
TM
CompactRF
OEM Spread Spectrum Transceiver
Revision 1.00, Sept 15, 2000
Microhard Systems Inc.
#110, 1144 - 29th Ave. N.E.
Calgary, Alberta T2E 7P1
Phone: (403) 248-0028
Fax: (403) 248-2762
www.microhardcorp.com
CompactRF
900 MHz
OEM Spread Spectrum
Transceiver
TM
This manual contains information of proprietary interest to
Microhard Systems Inc. It has been supplied in confidence to
purchasers and users of the CompactRF, and by accepting this
material the recipient agrees that the contents will not be copied
or reproduced, in whole or in part, without prior written consent
of Microhard Systems Inc.
Microhard Systems Inc. has made every effort to assure that this
document is accurate and complete. However, the company
reserves the right to make changes or enhancements to the
manual and/or the product described herein at any time and
without notice. Furthermore, Microhard Systems Inc. assumes
no liability resulting from any omissions in this document, or
out of the application or use of the device described herein.
Microhard Systems’ products are appropriate for home, office,
or industrial use, but are not authorized for utilization in
applications where failure could result in damage to property or
human injury or loss of life.
The electronic equipment described in this manual generates,
uses, and radiates radio frequency energy. Operation of this
equipment in a residential area may cause radio interference, in
which case the user, at his own expense, will be required to take
whatever measures necessary to correct the interference.
Microhard Systems Inc.
Leaders in Wireless Telecom
#110, 1144 - 29th Ave. N.E.
Calgary, Alberta T2E 7P1
Phone: (403) 248-0028
Fax: (403) 248-2762
www.microhardcorp.com
FCC Declaration of Conformity
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 caused undesired operation.
Microhard Systems Inc.’s products are warranted against all
failures which occur as a result of defective material or
workmanship within 12 months of purchase by the user. This
warranty does not extend to products that, in the opinion of
Microhard Systems Inc., have been subject to misuse, accidents,
lightning strikes, improper installation or application, nor shall
it extend to units which have, in Microhard Systems Inc.’s
opinion, been opened, tampered with or repaired by an
unauthorized facility.
© 2000 by Microhard Systems Inc., All Rights Reserved.
HyperTerminal is copyrighted by Hilgraeve Inc, and developed for Microsoft.
Microsoft and Windows are registered trademarks of Microsoft Corporation.
pcANYWHERE and Symantec are registered trademarks of Symantec Corp.
All other products mentioned in this document are trademarks or registered
trademarks of their respective holders.
Manual Revision 1.00, Sept 15, 2000.
ii CompactRFTM Operating Manual
Contents
1. Introduction
1.0 Product Overview .............................................................................................................................................................................. 1
1.1 Features.............................................................................................................................................................................................. 1
1.2 About this Manual............................................................................................................................................................................. 2
1.3 Unpacking and Inspection ................................................................................................................................................................. 3
2. Electrical/Physical
2.0 Functional Block Diagram................................................................................................................................................................. 5
2.1 Pinout................................................................................................................................................................................................. 6
2.2 DC Characteristics............................................................................................................................................................................. 8
2.3 AC Characteristics.............................................................................................................................................................................. 9
3. Mode of Operation
3.1 Data Mode ....................................................................................................................................................................................... 11
3.2 Command Mode .............................................................................................................................................................................. 12
3.2.1 Menu Interface......................................................................................................................................................................... 13
3.2.2 AT Command Interface........................................................................................................................................................... 13
3.3 Switching Between Command and Data Modes.............................................................................................................................. 14
3.3.1 Switching Between AT Command Interface and Data Mode................................................................................................... 14
3.3.2 Switching Menu Interface and Data Mode.............................................................................................................................. 15
3.4 Sleep Mode...................................................................................................................................................................................... 15
4. Configuration
4.1 Quick Start Approach ...................................................................................................................................................................... 17
4.2 AT Commands................................................................................................................................................................................. 18
4.3 AT Registers .................................................................................................................................................................................... 21
4.4 Configuration Settings..................................................................................................................................................................... 22
S Register 101 - Operating Mode..................................................................................................................................................... 23
S Register 102 - Serial Baud Rate.................................................................................................................................................... 25
S Register 104 - Network Address................................................................................................................................................... 26
S Register 105 - Unit Address.......................................................................................................................................................... 26
S Registers 106 and 206 - Primary and Secondary Hopping Patterns.............................................................................................. 26
S Register 107 - Encryption Key...................................................................................................................................................... 28
S Register 108 - Output Power Level............................................................................................................................................... 28
S Register 109 - Hopping Interval.................................................................................................................................................... 29
S Register 110 - Data Format............................................................................................................................................................ 29
S Registers 111 and 112 - Packet Minimum and Maximum Size..................................................................................................... 30
S Register 116 - Packet Character Timeout ...................................................................................................................................... 30
S Registers 113 and 213 - Packet Retransmission/Packet Retry Limit ............................................................................................. 31
S Register 115 - Packet Repeat Interval........................................................................................................................................... 31
S Register 122 - Link Handshaking.................................................................................................................................................. 32
S Register 117 - Modbus Mode ........................................................................................................................................................ 32
S Register 120 and 121- RTS/DCD Framing/Timeout ..................................................................................................................... 33
5. Installation
A. Modem Command Summary...................................................................................................................................................................... 41
B. Serial Interface............................................................................................................................................................................................ 43
C. Factory Default Settings.............................................................................................................................................................................. 45
D Performance Tables...................................................................................................................................................................................... 47
..... ..............................................................................................................................................................................
F. Technical Specifications............................................................................................................................................................................. 51
G. Development Board Schematics ................................................................................................................................................................. 53
H. Mechanical Drawing................................................................................................................................................................................... 59
I. Glossary...................................................................................................................................................................................................... 61
S Register 123 - RSSI Reading......................................................................................................................................................... 33
5.1 Estimating the Gain Margin............................................................................................................................................................. 35
5.2 Antennas and Cabling...................................................................................................................................................................... 37
5.2.1 Internal Cabling ....................................................................................................................................................................... 37
5.2.2 Installing External Cables, Antennas and Lightning Arrestors................................................................................................ 38
iii CompactRFTM Operating Manual
iv CompactRFTM Operating Manual
1. Introduction
1.0 Product Overview
The CompactRFTM is a high-performance embedded wireless data
transceiver. Operating in the 902-928 MHz ISM band, this frequencyhopping spread-spectrum module is capable of providing reliable wireless
data transfer between almost any type of equipment which uses an
asynchronous serial interface. The small-size and low operating current of
this module make it ideal for mobile and battery powered applications.
Typical uses for this module include:
n Automated Meter Reading (AMR);
n Vending Machines;
n Point of Sale Devices;
n Fleet Management;
n Telemetry;
n Remote Camera/Robot Control;
n Security Systems; and,
n Display Signs.
While a pair of CompactRFTM modules can link two terminal devices (“pointto-point” operation), multiple modules can be used together to create a
network of various topologies, including “point-to-multipoint” and “repeater”
operation. Multiple independent networks can operate concurrently, so it is
possible for unrelated communications to take place in the same or a nearby
area without sacrificing privacy or reliability.
1.1 Features
Key features of the CompactRFTM include:
n transmission within a public, license-exempt band of the radio
spectrum1 – this means that it can be used without access fees
(such as those incurred by cellular airtime);
n a serial I/O data port with handshaking and hardware flow
control, allowing the CompactRFTM to interface directly to any
equipment with an asynchronous serial interface.
1
902-928 MHz, which is license-free within North America; may need to be factory-configured
differently for some countries.
CompactRFTM Operating Manual: Chapter 1 Introduction. 1
n 30 sets of user-selectable pseudo-random hopping patterns,
intelligently designed to offer the possibility of separately
operating multiple networks while providing security, reliability
and high tolerance to interference;
n encryption key with 65536 user-selectable values to maximize
security and privacy of communications;
n built-in CRC-16 error detection and auto re-transmit to provide
100% accuracy and reliability of data;
n ease of installation and use – the CompactRFTM gives the user
the choice of a menu interface, or a subset of standard AT style
commands, very similar to those used by traditional telephone
line modems.
While the typical application for the CompactRFTM is to provide a short- to
mid-range wireless communications link between DTEs, it can be adapted to
almost any situation where an asynchronous serial interface is used and data
intercommunication is required.
1.2 About this Manual
This manual has been provided as a guide and reference for installing and
using CompactRFTM wireless transceivers. The manual contains instructions,
suggestions, and information which will help you set up and achieve optimal
performance from your equipment using the CompactRFTM.
It is assumed that users of the CompactRFTM have either system integration or
system design experience. Chapter 2 details the physical/electrical
characteristics of the module. Chapter 3 gives an overview of the modes of
operation. Chapter 4 describes the AT command register/menu setup and
configuration. Chapter 5 is an installation/deployment guide. The
Appendices, including the Glossary of Terms, are provided as informational
references which you may find useful throughout the use of this manual as
well as during the operation of the product.
Throughout the manual, you will encounter not only illustrations that further
elaborate on the accompanying text, but also several symbols which you
should be attentive to:
Caution or Warning: Usually advises against some action which could
result in undesired or detrimental consequences.
Point to Remember: Highlights a key feature, point, or step which is worth
noting, Keeping these in mind will make using the CompactRF more
useful or easier to use.
Tip: An idea or suggestion is provided to improve efficiency or to make
something more useful.
With that in mind, enjoy extending the boundaries of your communications
with the CompactRFTM.
2 CompactRFTM Operating Manual: Chapter 1 Introduction
1.3 Unpacking and Inspection
The following items should be found in the shipping carton. Inspect the
contents for any shipping damage. Report damages or shortages to the
distributor from which the unit was purchased. Keep all packing materials in
the event that transportation is required in the future.
Package contents for the CompactRF development kit (normal distribution):
1
CompactRFTM Wireless Module
2 Operating Manual (this document) 1
3 12V Wall Adapter 2
4 DB9 Straight-through Serial Cable 2
5 Rubber Duck Antenna 2
6
CompactRFTM Development Board
2
2
CompactRFTM Operating Manual: Chapter 1 Introduction. 3
4 CompactRFTM Operating Manual: Chapter 1 Introduction
2. Electrical/Physical
2.0 Functional Block Diagram
DVcc
AVcc
GND
\Config
\Reset
\Sleep
TxD
RTS
DTR
Comparator
A/D
IF Demod
-
+
SRAM
SRAM
Mixer
Frequency
Synthesizer
uC
8 bit data bus
UART
(DCE)
ARSSI
LNAMixer
Antenna
Switch
PA
GAIN
RSSI1-3
SYNC
RXMODE
TXMODE
EEPROM
RxD
CTS
DSR
DCD
CompactRFTM Operating Manual: Chapter 2 Electrical/Physical 5
2.1 Pinout
Figure 1 provides a top-view pinout drawing of the CompactRF module. The
corner pins (1,18,19,36) are labeled directly on the module.
NC
NC
NC
NC
\Config
SYNC
RSSI1
RSSI2
RSSI3
Rx Mode
Tx Mode
PGM
GND
GND
GND
GND
GND
AVcc
1
2
3
4
5
6
7
8
CompactRF
9
10
900MHz
11
12
13
14
15
16
17
18
T M
36
35
34
33
32
31
30
29
28
27
26
25
24
23
22
21
20
19
AVcc
GND
ARSSI
NC
NC
\Reset
DVcc
GND
TxD
RxD
GND
DSR
CTS
DCD
RTS
DTR
SCK
\Sleep
Figure 1 - Pinout (Top View)
Pin Name No. Description I/O
ARSSI 34 Provides an analog level of the received signal
strength. This is an uncalibrated signal, and will
provide only rough measurements of signal
strength.
AVcc 18,36 Positive Supply for Radio Circuitry. See Section
2.1 for DC Characteristics
\Config 5 Momentarily assert low to enter configuration
mode. See Section 2.2
CTS 24 RS-232 Clear to Send. Active low (TTL level)
output. See Appendix B for a complete description
of all RS-232 signals.
DCD 23 RS-232 Data Carrier Detect. Active low (TTL
level) output.
DSR 25 RS-232 Data Set Ready. Active low (TTL level)
output.
O
I
O
O
O
6 CompactRFTM Operating Manual: Chapter 2 Electrical/Physical
Pin Name No.
DTR 21
Description
RS-232 Data Terminal Ready. Active low
(TTL level) input.
I/O
I
DVcc 30
GND 13-17
26,29,
35
PGM 12
\Reset 31
SYNC 6
RSSI1 7
RSSI2 8
RSSI3 9
RTS 22
RxD 27
RXMODE 10
SCK 20
TxD 28
TXMODE 11
\Sleep 19
Positive Supply for Logic circuitry and I/O
pins. See Section 2.2 for DC Characteristics
Ground reference for logic, radio and I/O pins.
Programming Status indicator. This output is
for factory use only, and should normally be
left disconnected.
Active low reset input to the module. See
Section 2.3 for timing information.
Active high output indicates the modem is
synchronized with at least one other modem
Receive Signal Strength Indicator 1. This
output is the first of the three RSSI indicators
to become active high as the signal strength
increases. See Table 2 for details
Receive Signal Strength Indicator 2. This
output is the second RSSI indicator to become
active high as the signal strength increases.
See Table 2 for details.
Receive Signal Strength Indicator 3. This
output is the last RSSI indicator to become
active high as the signal strength increases.
See Table 3 for details.
RS-232 Request to Send. Active low (TTL
level) input.
RS-232 Receive Data. TTL level output.
Active high output indicates module is
receiving data over the RF channel.
ISP Programming Clock. Used in conjunction
with RxD and TxD when upgrading the
FLASH-based firmware.
RS-232 Transmit Data. TTL level input.
Active high output indicates module is
transmitting data over the RF channel.
Assert low to put the unit to sleep. See
Section 2.3 for timing information.
O
I
O
O
O
O
I
O
O
I
I
O
I
NC 1-4,
32,33
CompactRFTM Operating Manual: Chapter 2 Electrical/Physical 7
No Connect
For detailed mechanical drawings, refer to Appendix H
2.2 DC Characteristics
Sym Characteristic Min Typ Max Units
AV
DV
V
V
AI
AI
0
AI
1
AI
2
AI
3
AI
DI
DI
V
V
V
V
I
POT
RST
IL
IH
OL
OH
SRCE
Radio Supply Voltage 4.9 5.0 5.5 V
CC
Logic Supply Voltage 4.75 5.0 5.5 V
CC
Power On Reset Threshold Voltage 1.8 2 2.2 V
Reset Pin Threshold Voltage DVCC/
2
Radio Supply Current in Receive Mode 54 60 66 mA
CCR
Radio Supply Current at 1mW Transmit 68 75 82 mA
CCT
Radio Supply Current at 10mW Transmit 96 107 118 mA
CCT
Radio Supply Current at 100mW Transmit 185 206 227 mA
CCT
Radio Supply Current at 1W Transmit 517 575 633 mA
CCT
Radio Sleep Current 500 uA
SL
Logic Supply Current 22 25 28 mA
CC
Logic Sleep Current 1.0 mA
SL
Input Low Voltage (Pins 5,19,21,22,28) -0.5 .3DV
Input High Voltage (Pins 5,19,21,22,28) 0.6V
CC
Output Low Voltage (Pins 6-11,23-25,27) 0.6 V
Output High Voltage(Pins 6-11,23-25,27) 4.2 V
Sourcing Current (Pins 6-11,23-25,27) Per
Pin
CC
VCC+.5 V
10 mA
V
V
8 CompactRFTM Operating Manual: Chapter 2 Electrical/Physical
2.3 AC Characteristics
Sym Characteristic Min Typ Max Units
T
T
T
T
T
T
Reset Delay Time-Out Period 12.8 16.0 19.2 ms
TOUT
\Config. pulse duration See Note ms
CFG
\Sleep low to internal sleep delay 0 See Note ms
S2SD
Snooze duration 10 ms
SN
Sniff duration 100 us
SNIFF
\Sleep high to internal wakeup 0 T
WDLY
SN
ms
Note: The minimum duration for T
and is stored in register S109. The maximum delay for T
is one hop interval. The hop interval is set by the user,
CFG
is also one hop interval.
S2SD
Figure 2 provides timing information for both power-up reset and the \Reset
line operation. A fixed internal reset delay timer of roughly 16ms is triggered
as the V
Internal Reset
or V
POT
\Reset
threshold is reached.
RST
CC
VDV
POT
V
RST
T
TOUT
Figure 2. Reset Timing
Figure 3 illustrates the sleep operation for the CompactRF. When the \Sleep
line is asserted, the modem will internally go to sleep within one hop interval.
While sleeping, the modem will “sniff” every 10 ms to check if the \Sleep
line has again gone high. If the \Sleep line is low, the modem goes back to
sleep. If it is high, the modem wakes up and resumes normal operation.
\Sleep
T
S2SD
\Internal Sleep
T
SN
T
SNIFF
T
WDLY
Figure 3. Sleep/Wakeup Timing
CompactRFTM Operating Manual: Chapter 2 Electrical/Physical 9
10 CompactRFTM Operating Manual: Chapter 2 Electrical/Physical
3. Modes of Operation
The CompactRFTM modem can be easily configured to meet a wide range of
needs and applications. The module is designed such that all
communication is through one serial port (Pins 21 to 28 on the module).
This port has two functions:
1. It provides the asynchronous interface with the host equipment for data
that is sent/received on the RF channel. When operating in this fashion,
the module is said to be in data mode.
2. It is also used for configuring and programming the module. When
operating in this fashion, the module is said to be in command mode.
In addition to data mode and command mode, there is a third mode of
operation called sleep mode. The module will always be in one of these
three modes.
3.1 Data Mode
Data mode is the normal operating mode of the CompactRF. When in data
mode, the CompactRF is communicating with other CompactRF modules,
and facilitating wireless asynchronous serial communication amongst two or
more terminal devices. There are three basic elements to any CompactRF
communications network:
• One module configured as the Master
• Zero or more modules configured as Repeaters
• One or more modules configured as Slaves
The function of the Master is to provide synchronization for the entire
network, and to control the flow of data. There is always one Master per
network. The Master is the ultimate destination for all data collected at the
various Repeater’s and Slave’s serial ports. With the network set up for
Point-to-Multipoint communication, all data received at the Master’s serial
port is transmitted to every Repeater and Slave in the network. The
CompactRF is a frequency hopping transceiver, meaning that it “hops” to a
new frequency after a predetermined time interval. This time interval is a
fixed time set by the user, and can range from 14ms to 180ms. The
CompactRF hops according to a pseudorandom pattern of 50 different
channels.
CompactRFTM Operating Manual: Chapter 3 Modes of Operation 11
M
Network 1
MSRM
Network 2
S
M
Network 3
M
Network 4
When configured as a Slave, the CompactRF searches for synchronization
with a Master. Network topologies consisting of a single Master and
S
virtually any combination of Slaves and Repeaters may be deployed. The
functionality of any particular CompactRFTM can be configured as follows:
n Master Point-to-Point: The modem is configured to
communicate with a single Slave, either directly, or through one
or more Repeaters.
SR
n Master Point-to-Multipoint: The modem is configured to
communicate with one or more Slaves and/or Repeaters.
n Slave: The modem is configured to communicate with one
Master either directly or through one or more Repeaters..
n Repeater: The modem is configured to pass information from
either a Master or another Repeater onto subsequent Repeaters
and/or Slaves and vice versa. The Repeater also acts as a Slave
S
in the sense that, like a Slave, it passes information to/from its
serial port.
S
Examples of different network topologies are shown in Figure 4. Network
1 shows Point-to-Point communication between a Master and Slave.
Network 2 makes use of a Repeater to communicate with the Slave.
Network 3 illustrates a simple Point-to-Multipoint network with no
S
R
Repeaters. Networks 4 and 5 gives examples of Point-to-Multipoint
networks consisting of both Repeaters and Slaves. There is effectively no
restriction to the number of Repeaters and Slaves that can be added to a
network. As seen in Network 4, a Master can communicate directly with
S
S
both Slaves and Repeaters.
3.2 Command Mode
M R
S
Network 5
Figure 4 - Sample Network
Topologies. Virtually any
Combination of Slaves and
Repeaters May be Used.
SR
between two different Command Mode interfaces: Menu Interface; or, AT
Command Interface. The menu interface is ideal for applications which
involve human configuration of the operating parameters of the modem.
The AT Command interface is more suited for direct interface with another
microcontroller or for higher level Windows-based software applications.
The CompactRF development board is a useful tool for familiarizing
yourself with the various operating parameters and user interface.
Reference schematics for the development board can be found in Appendix
G. To access the CompactRF’s command mode using the development
board:
1. Insert the module into the socket with the antenna connector towards
the edge of the board.
2. Attach the supplied antenna.
3. Connect a straight through serial cable between the DB9 connector and
the serial port on your PC
4. Apply power to the development board
5. Run any terminal application program such as Hyperterminal
6. Set the serial port to 9600 baud, 8N1
7. Momentarily press the configure (CFG) button
The CompactRF firmware has been designed to allow the user to select
12 CompactRFTM Operating Manual: Chapter 3 Modes of Operation
Menu selections are
immediately stored to the
module’s non-volatile
memory.
3.2.1 Menu Interface
At this point, you should see a menu similar to the following appear:
Microhard Systems Inc
CompactRF Configuration
1) Operating Mode S101=1 MasterPP 2) Serial Baud Rate S102=4 9600
3) Network Address S104=255 4) Unit Address S105=65535
5) Hopping Pattern S106=0 6) Encryption Key S107=65535
7) Output Power Level S108=0 1 mW 8) Retry Limit S213=255
9) Hop Interval S109=20 x 0.74 ms = 14 ms
D) Autoanswer S0=1 E) Interface S6=0 AT style
A) Handshaking &K3 Enabled N) DTR &D0 Ignored
O) DSR &S0 ON in Data Mode M) DCD &C1 ON when sync'd
S2=43 S3=13 S4=10 S5=8
Type AT for AT interface or hit Enter for menu
You now have the option of choosing between the menu interface, or the AT
Command interface.
For menu operation, hit ENTER. You should see the following prompt:
Enter Command :
Now, the CompactRF will respond to your menu selection. For example, to
change the unit’s Operating Mode, press the 1 key. The following sub-menu
will appear:
Operating Mode
* 1) MasterPP
2) SlavePP
ESC to exit
Select Operating Mode :
The instant a selection is made, it is immediately stored into the module’s
non-volatile memory.
3.2.2 AT Command Interface
The CompactRF may also be controlled through an AT Command line
interface, using a command set which is very similar to a traditional Hayes
telephone modem command set.
For AT Command operation, instead of hitting ENTER at the prompt, type
AT <ENTER>. The characters ‘AT’ are known as the attention characters
and must be typed at the beginning of each command line. The modem
should respond with OK. Illustrating the same example as above to
configure the Operating Mode using AT Commands, type the following:
ATS101=2 <ENTER>
The modem should respond with ’OK.’ The above command will set the
operating mode to SlavePP (Slave Point to Point).
CompactRFTM Operating Manual: Chapter 3 Modes of Operation 13
When using AT Commands,
use the &W command to
store the most current
settings to memory.
With AT Commands, the settings are not immediately stored to non-volatile
memory, therefore if the modem is powered down at this point, the
Operating Mode would revert to its previous value. To store any recently
updated command registers, the following “write” command must be
entered.
AT&W <ENTER>
3.3 Switching Between Command and Data Modes
The method for switching between data and command modes depends on
which interface you are using (Menu or AT). There is a parameter called
“Interface” (Menu item E) which defines whether the modem is currently
operating in AT mode or Menu mode.
3.3.1 Switching Between AT Command Interface and Data
Mode
Your modem must be in Command Mode for it to execute a command. If
you send characters when the modem is in Data Mode, the modem transmits
the characters over the air.
Depending on its settings, the modem will either power up in Command
Mode or Data Mode. Normally, when first received from the factory, the
unit will power up in Command Mode. In this mode of operation, the
module “autobauds,” meaning that it will adapt to the baud rate of the DTE
equipment to which it is connected. Therefore, when in Command Mode,
you may change the baud rate of your equipment, and the CompactRF will
automatically adjust to this baud rate once an AT string is issued. The new
baud rate is stored in register S102. Several baud rates ranging from 2400
to 19200 may be selected.
You can place the modem into Data Mode either by:
• Issuing the answer command (ATA <ENTER>); or,
• Issuing the online command (ATO <ENTER>).
14 CompactRFTM Operating Manual: Chapter 3 Modes of Operation
The modem will now attempt to communicate with other CompactRF
modules. While in Data Mode, the modem will communicate through the
serial port at the same baud rate as was last used in Command Mode2.
To return to Command Mode, you can either:
The escape sequence will not
be accepted unless both the
CompactRFTM and the
terminal are set to the same
baud rate
\SLEEP \CONFIG
DATA
MODE
ESC \SLEEP
COMMAND
MODE
ESC \SLEEP
\SLEEP \CONFIG
\SLEEP
\SLEEP
\SLEEP
SLEEP
MODE
\SLEEP
Figure 5a - Menu
Interface State Diagram
\SLEEP
DATA
MODE
• Send the escape sequence. (The escape sequence consists of 1 second
of inactivity, followed by the characters ‘+++’ followed by another
second of inactivity.); or,
• Toggle the DTR line (depending on the &D parameter see pg 11).
The escape sequence must be issued at the baud rate that the modem has
been set to. If the modem is set to 19200 baud, and the escape sequence is
issued at 9600 baud, for example, the modem will not recognize it, and will
not go into Command Mode.
3.3.2 Switching Between Menu Interface and Data Mode
When configured for Menu Interface operation, the CompactRF may be
placed into Command Mode from Data Mode by momentarily asserting the
\Config line. This line runs out to a pushbutton on the development board.
Press this button and wait for the menu interface to appear on the screen.
The terminal must be set to 9600 baud when using the menu interface.
To switch back to Data Mode, from the main menu, hit the ESC key. You
should see the response “Running...” The modem will run in Data Mode at
the baud rate setting defined by Menu Item 2) Serial Baud Rate.
3.4 Sleep Mode
As mentioned at the beginning of this chapter, the CompactRF has a sleep
mode of operation. Figure 5 is a state diagram representation of the three
modes of operation. Figure 5a is the menu interface state diagram, and
Figure 5b is the AT interface state diagram. The CompactRF enters into
Sleep Mode when \SLEEP is asserted (active low). The module remains in
Sleep Mode until this line is deasserted. See Chapter 2 for timing
information. When in Sleep Mode, the module drives all outputs pins (Pins
6-11,23-25,27) at their inactive levels.
(ATA or ATO Command)
COMMAND
MODE
DTR or
Escape Sequence
\SLEEP
\SLEEP
\SLEEP
SLEEP
MODE
2
It is possible to enter into Data Mode at a different baud rate from what is
currently being used in Command Mode by issuing the command
ATS102=x, where x is one of the valid baud rates. Care must be taken
when setting the baud rate in this manner. If you issue another AT string
after attempting to set the baud rate using ATS102 <ENTER>, the modem
will again autobaud and automatically revert to the baud rate of the host
\SLEEP
\SLEEP
Figure 5b - AT Interface
State Diagram
equipment. For example, if your equipment is running at 9600 baud and
you wish to set up the modem to run at 19200 baud, the following command
line entry would achieve this:
ATS102=2&WA <ENTER>
The first part (S102=2) sets the baud rate to 19200. The next characters
(&W) write this baud rate to memory. The last character (A) puts the
modem into Data Mode. Once in Data Mode, the modem is unable to
autobaud, and is fixed at 19200 baud. By combining several commands into
one command line entry, and then immediately putting the modem online,
the modem is not given a chance to autobaud back to 9600.
CompactRFTM Operating Manual: Chapter 3 Modes of Operation 15
16 CompactRFTM Operating Manual: Chapter 3 Modes of Operation
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