ST SPWF04S Series User Manual

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User manual

TCP/IP protocol stack for SPWF04Sx Wi-Fi modules

Introduction

The SPWF04Sx series of Wi-Fi modules integrate a complete TCP/IP protocol stack and a rich set of applications including, but
not limited to, web server, web client RESTful API, TFTP, MQTT and SMTP.

Security is added in the multiple layers of Wi-Fi and peer-to-peer protocols. The stack implements the WPS protocol, WPA2 in
both the Personal and Enterprise options, and the TLS for end-to-end secure transactions.

Users access the features of the SPWF04Sx modules via UART using the simple AT command syntax, or via SPI using a
custom packet format and protocol.

To enable a complete customization of the application on the module, the SPWF04Sx software integrates a MicroPython
interpreter that provides the user with MicroPython standard libraries and a customized set of classes to export the specific
SPWF04Sx features.

The diagram below summarizes the possible integrations of an SPWF04Sx module in a target application.

Figure 1. SPWF04Sx user integration modes

This user manual is intended as a guide to the set of commands available on the UART or the SPI console. A description and
explanation of the configuration variables, status variables and asynchronous indication messages is available in the Appendix
of the manual.

This manual is not intended as a technical guide of Wi-Fi and TCP/IP, or other technologies available in the module.

UM2114 - Rev 3 - November 2018
For further information contact your local STMicroelectronics sales office.

www.st.com

SPWF04Sx software architecture description

1 SPWF04Sx software architecture description

The complete SW architecture of SPWF04S is shown in the diagram below.

Figure 2. SPWF04Sx software architecture

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A block diagram of the SPWF04Sx protocol stack is provided in Figure 3. SPWF04Sx protocol stack diagram.

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SPWF04Sx software architecture description

Figure 3. SPWF04Sx protocol stack diagram

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2 Interface and message types

As shown in Figure 1. SPWF04Sx user integration modes, the SPWF04Sx enables three options for integration of
the device in the final user application. Refer to the SPWF04Sx datasheet for information useful for
implementation, such as the pinout. The configuration variable, “console_enabled”, is used to define the module
interface to use.

• UART interface

“console_enabled=1”

The UART console provides a user-friendly interface built on a set of AT commands that allow an external
microcontroller connected to the SPWF04Sx UART to access the functions integrated in SPWF04Sx device.
UART is set as the module's default interface.

• SPI interface

“console_enabled=0”

The device can be connected as a slave to the SPI interface of an external microcontroller. An ad hoc SPI
protocol and corresponding packet format are defined.

• MicroPython scripting

"console_enabled=2” - to use Python together with AT commands over UART.

"console_enabled=3” - to use MicroPython only.

The device implements a scripting methodology based on an integrated MicroPython interpreter.
MicroPython scripts can map a target application, making it unnecessary to integrate the device with an
external processor.

The following four message types represent the type of data exchanged over the interfaces.

• Commands

Used to activate a feature defined within the stack. The list of commands supported is specified in

Table 1. SPWF04Sx commands.

• Command return messages

Synchronous messages that report the status of the execution of a command. The list of synchronous error
codes is reported in Section 8 in the Appendix.

• WINDs

Asynchronous messages reporting a network or radio status at the application level. The list of WIND
messages is reported in Section 8 in the Appendix.

• Data

Data sent to, or received (data payload) from, a remote device.

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Interface and message types

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Table 1. SPWF04Sx commands

Command ID

Utils: commands for debugging and retrieving module status

0x01 AT Null command

0x02 AT+S.HELP Help command

0x05 AT+S.STS Status configuration

0x35 AT+S.PEERS Peers configuration

Management: commands for module management and configuration

0x03 AT+S.RESET SW reset

0x04 AT+S.PMS Set power mode

0x08 AT+S.PYTHON Enter MicroPython execution

0x09 AT+S.GCFG Read Configuration status

AT command Description

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Command ID AT command Description

0x0A AT+S.SCFG Set configuration variables

0x0B AT+S.WCFG Save configuration to Flash

0x0C AT+S.FCFG Restore factory configuration

0x57 AT+S.FSWRITE FS update via serial UART/SPI

0x58 AT+S.FSUPDATE FS download

0x56 AT+S.FWUPDATE FW download

STM32 peripherals: commands to manage the peripherals and related values

0x13 AT+S.GPIOC Configure GPIO

0x14 AT+S.GPIOR Read GPIO

0x15 AT+S.GPIOW Write GPIO

0x16 AT+S.DAC Disable/Enable DAC

0x17 AT+S.ADC Read ADC value

0x18 AT+S.PWM Set PWM

0x11 AT+S.TIME Get/Set time

0x12 AT+S.RANDOM Provide random number

File system management

0x21 AT+S.FSM Mount volume

0x22 AT+S.FSU Umount/Erase volume

0x23 AT+S.FSC Create file, append data

0x25 AT+S.FSD Delete file

0x26 AT+S.FSR Rename file

0x27 AT+S.FSL List existing files

0x28 AT+S.FSP Print file content

0x29 AT+S.HASH Compute digest

Security: commands to interact with the security features

0x2A AT+S.WPAECERT Manage WPA-Enterprise certificates

0x2B AT+S.TLSCERT Manage TLS certificates

0x36 AT+S.WPS Initiate a WPS Exchange

Radio: commands to manage main Wi-Fi operations

0x32 AT+S.WIFI Set Wi-Fi radio

0x33 AT+S.SCAN Network scan

0x34 AT+S.SSIDTXT Get/Set ASCII SSID

0x39 AT+S.PING Ping a specified host

Sockets: commands to manage socket read and write

0x41 AT+S.SOCKON Open a socket client

0x42 AT+S.SOCKQ Query a socket client for pending data

0x43 AT+S.SOCKC Close a socket client

0x44 AT+S.SOCKW Write data to a socket server

0x45 AT+S.SOCKR Read data from a socket client

0x46 AT+S.SOCKL List opened socket clients

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Interface and message types

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Interface and message types

Command ID AT command Description

0x47 AT+S.SOCKDON Open a socket server

0x48 AT+S.SOCKDQ Query socket server for pending data

0x49 AT+S.SOCKDC Close a socket server

0x4A AT+S.SOCKDW Write data to a socket server

0x4B AT+S.SOCKDR Read data from a socket server

0x4C AT+S.SOCKDL List bound socket clients

Web sockets

0x61 AT+S.WSOCKON Open a web socket client

0x62 AT+S.WSOCKQ Query a web socket client for pending data

0x63 AT+S.WSOCKC Close web socket client

0x64 AT+S.WSOCKW Write data to a web socket client

0x65 AT+S.WSOCKR Read data from web socket client

0x66 AT+S.WSOCKL List open web socket client

Trivial FTP

0x51 AT+S.TFTPGET Get request to a TFTP server

0x52 AT+S.TFTPPUT Put request to a TFTP server

SMTP

0x53 AT+S.SMTP Send an email

HTTP

0x54 AT+S.HTTPGET Get a request to an HTTP server

0x55 AT+S.HTTPPOST Post request to an HTTP server

0x59 AT+S.INPUTSSI Fill buffer for raw text input SSI

MQTT

0x5A AT+S.MQTTCONN MQTT connect

0x5B AT+S.MQTTSUB MQTT subscribe

0x5C AT+S.MQTTPUB MQTT publish

0x5D AT+S.MQTTUNSUB MQTT unsubscribe

0x5E AT+S.MQTTDISC MQTT disconnect

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3 AT commands over the UART

The factory module configuration sets the UART console mode as the default interface for the SPWF04Sx. This
corresponds to the configuration variable “console_enabled” being set to 1.

AT commands over the UART have a max length of 512 bytes; they are case insensitive and are always in the
form of:

AT+S. <cmd-parameters><cr>[data]

Note: Any command requiring data after the <cr> is not reentrant. If bytes are lost during data transfer over the

UART, the module remains in the waiting stage for incoming bytes.

A command is followed by a variable number of response lines that have the following format:

AT-S. <response-string><optional-parameters>

The AT command line, up to the terminating <cr>, is sent from the host. Response lines are sent from the module
to the host.

AT-S.OK:<free_heap>:<wifi_state>

AT-S.ERROR:<error-code>:<error-string>

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AT commands over the UART

returned when a command is successfully executed.

Note that free_heap and wifi_state are shown depending on
the "console_verbose" configuration variable value (0 to 2).

qualifies a synchronous error. The <error-code> field of each
asynchronous indication type is unique. The descriptive string
may be safely ignored.

Note that error_code and error_string are shown depending
on the "console_errs" configuration variable value (0 to 2).

Command parameters

A command can require parameters that follow an “=” character. The parameters are positional and separated by
a configurable separator (by default, a comma).

Parameters can require mandatory or optional values. In the latter case, if the value is not specified a default
value will be used. In the format of the command, an optional parameter is represented in squared brackets.

Asynchronous indications

Asynchronous indications may arrive at any time (except as noted below), and have the format:

+WIND:<number>:<descriptive-string>[:<variables>]<cr><lf>

The <number> field of each asynchronous indication type is unique. The descriptive string may be safely ignored.

Note that number and descriptive strings are shown depending on the "console_winds" configuration variable
value (0 to 2).

Refer to Section 8 in the Appendix for a complete list of WIND messages.

Note: Immediately after reset, no commands should be sent and only asynchronous indications are present until
the indication “+WIND:0:Console active<cr><lf>” is received. After this event, AT commands may be safely sent to
the device.

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4 SPI protocol

By setting to 0 the configuration variable "console_enabled", the module is enabled to use the SPI interface in
place of the UART.

The data transferred over the MISO and MOSI signals are packed using a well-defined API packet format as
represented below.

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SPI protocol

Figure 4. SPI packet formats

Table 2. KindOfEvent Byte SubField

Bits 0:3

Bits 4:7

Bits

Status variable wifi_state values range. Refer to

Table 8. Status variables.

Allowed values are:

• 0x01 for common indications like WIND or action
confirmations

• 0x02 for critical error notifications

• 0x03 for incoming data sent over the SPI (in this case
normally data are filled into payload field)

Event type

Table 3. Indication number field

Event type Bits 4:7

0x01 Refer to Table 14. WIND messages.

0x02

0x03 Data payload.

Refer to Table 10. AT-S.ERROR:=ERROR ID= =ERROR

String=.

Indication number

Commands over the SPI have a max length of 512 bytes.

To map an AT command in the equivalent SPI command, the following procedure applies:

1. Use the corresponding CMD ID specified in Table 1. SPWF04Sx commands and fill the 4th bytes of the
master packet.

2. If optional parameters are available, count the number of comma-separated items after the “=” character and
with that number the 6th byte of the message. Starting from the 7th byte, start to write 1 byte containing the

field lengths and then copy the field bytes. Then continue with the remaining parameters.

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SPI protocol

3. Once the full payload has been filled, calculate the full message payload lengths and accordingly fill bytes 1
and 2 in the SPI message packet request.

First example

AT command: AT+S.FSL

1. Command ID: 0x25

2. Number of parameters: 0x00

3. Full message payload length: 0x02

Result: SPI message 0x02 0x00 0x02 0x25 0x00

Second example

AT command: AT+S.SCAN=d,/scan.txt

1. Command ID: 0x33

2. Number of parameters: 0x02

a. First Parameter: 0x01,d

b. Second Parameter: 0x09,"/scan.txt"

3. Full message payload length: 0x0D

Result: SPI Message 0x02 0x00 0x0D 0x33 0x02 0x01 d 0x09 "/scan.txt"

Third example

AT command: AT+S.SOCKW=0,5<Cr>hello

1. Command ID: 0x44

2. Number of parameters: 0x02

a. First Parameter: 0x01,0

b. Second Parameter: 0x01,5

3. Payload: "hello"

Result: SPI Message 0x02 0x00 0x0B 0x44 0x02 0x01 0 0x01 5 "hello"

Fourth example

Asynchronous event: +WIND:1:Poweron:170726-b7ac1ba-SPWF04S

1. kind of event (4bits): 0x01

2. wifi_state (4 bits): 0x0

3. Indication number: 0x01

4. Full message payload length: 0x16

Result: SPI Message 0x02 0x10 0x01 0x16 0x00 (170726-b7ac1ba-SPWF04S)

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5 MicroPython scripting

The SPWF04Sx supports the MicroPython modes represented in Figure 5. MicroPython modes. The configuration
variable “console_enabled” identifies the use of the console together with MicroPython. In detail:

• "console_enabled" set to 2: this setting allows using both AT commands over the UART and MicroPython
REPL shell.

• "console_enabled" set to 3: this setting allows only a MicroPython preloaded script to be executed. No
UART/SPI communication is allowed to/from a host processor.

Consequently, the following Python modes are defined:

• Python Interactive Console (REPL – Read Evaluation Print Loop). Mainly used for debugging purposes,
it is activated by the AT+S.Python (Python command) launched without parameters. The REPL is exited by
using a CTRL-D escape character.

• Run Time Script execution. Activated with the Python command, it allows to execute the script specified as
parameter. After script execution, control returns to the AT console.

• DefaultScript Hard Execution. By using the GPIO(8) set to high at boot time, or when "console_enabled" is
set to 3, the module automatically enters the execution of the script specified by the variable “python_script”.
This mode allows the use of the module without a connected host. Note that "console_enabled" is not
changed by GPIO(8) access: this means that on the subsequent reboot, accessing Python mode again will
require GPIO(8) to be high.

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MicroPython scripting

Figure 5. MicroPython modes

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6 Command reference guide

This section details each of the SPWF04Sx commands listed in Table 1. SPWF04Sx commands, including a brief
description of its behavior and complete list of parameters. Examples and syntax are described in the “AT” format
introduced in Section 3 AT commands over the UART. The mapping mechanism described in Section 4 SPI

protocol is used to map the AT command in the packet format used by the SPI.

6.1 AT

AT, by itself, is a null command that always returns an OK result code. It is useful for testing the module interface
for readiness.

Usage:

AT<cr>

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Command reference guide

Parameters:

None

6.2 AT+S.HELP

AT+S.HELP prints the list of all the AT commands supported with a brief help text for each of them. Refer to

Table 1. SPWF04Sx commands for a complete list of the commands available.

Usage:

1) AT+S.HELP<cr>

2) AT+S.HELP=<keyword><cr>

Parameters:

<keyword>

Result:

to get the full list of commands

to get the list of commands containing the specified keyword

Specifies the name of a keyword

AT-S.Command:<command> -- <help>

<command>

<help>

6.3 AT+S.STS

AT+S.STS displays the current values of all the status variables.

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Specifies the command

Specifies the description of the command

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Usage:

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AT+S.PEERS

1) AT+S.STS<cr>

2) AT+S.STS=<variable><cr>

Parameters:

<variable>

Result:

AT-S.Var:<var>=<value>

<var>

<value>

6.4 AT+S.PEERS

AT+S.PEERS displays the current values of the peer table. These values are useful to obtain additional
information about the module connected to the AP or about the client connected to the module when it is
configured in Mini AP mode.

Usage:

to get the full list of configuration variables

to get the value of the specified variable

Specifies the name of a variable. See Table 8. Status

variables for a list of the available status variables

Specifies the status variable name

Specifies the status variable value

1) AT+S.PEERS<cr>

2) AT+S.PEERS=<peer_number><cr>

3) AT+S.PEERS=<peer_number>,<peer_var><cr>

Parameters:

<peer_number>

<peer_var>

Result:

AT-S.Var:<id>.<var>=<value>

<id>

returns the list of peers variable

returns the list of peers variable for the peer_number peer

returns the specific value of a peer_variable

identifier of the peer

displays the current value of the specified peer variable. Refer
to Table 9. Peer variables in the Appendix for a complete list
of the peer variables

Specifies the peer number

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AT+S.RESET

<var>

<value>

6.5 AT+S.RESET

Command used to provide a SW reset to the module.

Usage:

AT+S.RESET<cr>

Parameters:

None

6.6 AT+S.PMS

The SPWF04Sx features different power states as a consequence of the different operating modes of the radio
and the STM32 microcontroller. This command is used to manage the module power state.

The table that follows summarizes the power state conditions supported by the module. The values of the
variables affecting the output of the command are also reported in the following table.

Specifies the peer variable name

Specifies the peer variable value

Table 4. Power states and configuration

Module state <Mode> option value STM32 state WLAN state AT variable default values

Rx Idle

Active 0 Run

(1)

PowerSave

(1)

Sleep

StandBy

1. Variables wifi_beacon_wakeup, wifi_operational_mode, and wifi_listen_interval, need to be set to the desired value.

2. The variable standby_time to be set to the desired value.

(2)

1 Run PS or Fast PS

2 Stop PS or Fast PS

3 Standby Off

Rx Active

Tx Active

AT+S.SCFG=sleep_enabled,0

AT+S.SCFG=wifi_powersave,0

AT+S.SCFG=standby_enabled,0

AT+S.SCFG=sleep_enabled,0

AT+S.SCFG=standby_enabled,0

AT+S.SCFG=wifi_powersave,1

AT+S.SCFG=sleep_enabled,1

AT+S.SCFG=standby_enabled,0

AT+S.SCFG=wifi_powersave,1

AT+S.SCFG=standby_enabled,1

AT+S.SCFG=sleep_enabled,0

Usage:

AT+S.PMS=[<mode>]<cr>

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Parameters:

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<mode>

6.7 AT+S.PYTHON

The command has a Python script executed when the file name is specified or allows to enter a Python shell
when the option is not used.

Usage:

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AT+S.PYTHON

Default value: 0

Possible values:

• 0 → active mode

• 1 → powersave mode

• 2 → stop mode

• 3 → standby mode

1) AT+S.PYTHON<cr>

2) AT+S.PYTHON=<filename><cr>

Parameters:

<filename>

6.8 AT+S.GCFG

This command lists all the configuration variables together with their current value.

Usage:

1) AT+S.GCFG<cr>

2) AT+S.GCFG=<cfg_var><cr>

Parameters:

to enter the MicroPython REPL shell.

to execute the specified script.

specifies the Python script to be executed. After the execution
of the script the command returns to the AT console.

to get the full list of configuration variables

to get the value of the specified variable

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<cfg_var>

Result:

AT-S.Var:<var>=<value>

<var>

<value>

configuration variable. Refer to Table 7. Configuration

variables for a complete list of the configurable variables.

Specifies the configuration variable name

Specifies the configuration variable value

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6.9 AT+S.SCFG

Command to set the value of the named configuration variable. The value is saved in the RAM until the command
AT+S.WCFG is used.

Usage:

AT+S.SCFG=<key>,<value><cr>

Parameters:

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AT+S.SCFG

<key>

<value>

6.10 AT+S.WCFG

Command to save the configuration set to the Flash.

Usage:

AT+S.WCFG<cr>

Parameters:

None

6.11 AT+S.FCFG

Command to restore the factory configuration variables from the Flash. It is mandatory to run a reset (HW or SW)
after a factory restore.

Usage:

variable to configure

value to be set

AT+S.FCFG<cr>

Note: HW factory restore of the variables is performed by pulling the pin GPIO0 high at power-up (until the

“+WIND:1:Poweron” indication is printed). In order to use the HW factory reset (GPIO0 enabled) and
FWUPDATE at the same time, see Section 6.13 AT+S.FSUPDATE.

Parameters:

None

6.12 AT+S.FSWRITE

The command is used to update the external volume via serial interface.

Note: The HW flow control MUST be enabled in order to use the command via UART.

Usage:

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AT+S.FSWRITE=<length><cr>{data}

Parameters:

<length> Data length to send (in bytes)

6.13 AT+S.FSUPDATE

To download an updated file system from the named host and path. The downloaded image overwrites the
existing one. In this case, the user needs to perform a backup of the current file system.

Usage:

AT+S.FSUPDATE=<mem>,<hostname>,[<path&queryopts>],[<port>],[<TLS>],[<username>],
[<passwd>]<cr>

Parameters:

<mem>

<hostname>

<path&queryopts>

<port>

<TLS>

<username>

<passwd>

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AT+S.FSUPDATE

specifies the memory where the file system is saved.

• e → user Flash

• i → application Flash

• x → external memory volume

Target host. DNS resolvable name or IP address.

Default:/fs.img. Document path and optional query arguments.

Default 80 (if TLS=0) or 443 (if TLS>0).

Default: 0. Values range: 0 → unsecured; 1 → autodetect; 2
→ TLS

Default: none.

Default: none.

6.14 AT+S.FWUPDATE

This command downloads an updated firmware image located at the named host and path. The downloaded
image is temporary stored in the internal Flash. The user should perform a procedure to save the content of the
file system that will be overwritten during the process.

Note: FWUPDATE can be invalidated by pulling GPIO0 high during the first reset after the execution of AT

+S.FWUPDATE command. In this case, the external filesystem is erased and the FW update is not performed.

Usage:

Note: The HW factory reset pin (GPIO0) must be tight low during F/W update. The HW factory reset can be used after

“+WIND:17:F/W update complete!”

AT+S.FWUPDATE=e,<hostname>,[<path&queryopts>],[<port>],[<TLS>],[<username>],
[<passwd>]<cr>

Parameters:

<hostname>

Target host. DNS resolvable name or IP address.

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AT+S.GPIOC

<path&queryopts>

<port>

<TLS>

<username>

<passwd>

6.15 AT+S.GPIOC

Command used to configure the function of the various GPIOs on the module. GPIOs can be configured as inputs
or outputs. When used as inputs, they generate an interrupt when the state changes that can be configured on
the signal edge.

Usage:

1) AT+S.GPIOC=<number>,out<cr>

2) AT+S.GPIOC=<number>,in,

[<interrupt>]<cr>

Parameters:

Default: /fw.fota. Document path and optional query
arguments. If a secure FOTA is required, the extension of the
file needs to be “.sfota”.

Default 80 (if TLS=0) or 443 (if TLS>0).

Default: 0. Values range: 0 → unsecured; 1 → autodetect; 2
→ TLS

Default: none.

Default: none.

to configure a gpio as an output

to configure a gpio as an input

<number>

<interrupt>

6.16 AT+S.GPIOR

AT+S.GPIOR is used to read the value and the direction of a previously-configured GPIO.

Usage:

AT+S.GPIOR=<num><cr>

Parameters:

<num>

Result:

GPIO Number (see Datasheet)

Default: No interrupt (turn it off, if enabled). It can assume one
of the following values:

• R → Rising edge

• F → Falling edge

• B → Both rising and falling edges

specifies the GPIO to read

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AT-S.Value:<num>:<level>:<direction>

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AT+S.GPIOW

<num>

<level>

<direction>

6.17 AT+S.GPIOW

AT+S.GPIOW is used to set the value of a previously-configured output GPIO.

Usage:

AT+S.GPIOW=<num>,<level><cr>

Parameters:

<num>

<level>

6.18 AT+S.DAC

The DAC command enables DAC on GPIO15.

Usage:

Specifies the number of GPIO read

0 (low) or 1 (high)

0 (output pullup) or 1 (input)

specifies the GPIO to be set

specifies one possible value(0|1) for the specified GPIO.

AT+S.DAC=<value><cr>

Parameters:

<value>

6.19 AT+S.ADC

AT+S.ADC returns ADC value on the selected GPIO. The value range is between 0 and 3300 mV with a
measurement accuracy of 10 mV.

Usage:

AT+S.ADC=<num><cr>

Parameters:

<num>

must be set in mV (between 1 and 3300). The value=0
disables DAC on GPIO15

specifies the GPIO to be used for conversion. Available
GPIOs are 0, 1 and 16

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Result:

AT-S.Value:<value>

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AT+S.PWM

<value>

6.20 AT+S.PWM

The PWM command enables PWM on the selected GPIO, with a specified frequency and duty-cycle.

Usage:

AT+S.PWM=<num>,<frequency>[,<duty_cycle>]<cr>

Parameters:

<num>

<frequency>

<duty_cycle>

6.21 AT+S.TIME

Command to get or set the time (date, time)

Usage:

Specifies the ADC value

specifies the GPIO to be used for PWM. Available GPIOs are
2 and 4

value between 1 and 10 kHz. The value=0 disables PWM

default: 50%. The value is in the 0 - 100 range.

1) AT+S.TIME<cr>

2) AT+S.TIME=<time>

Parameters:

<time>

Result:

AT-S.Date:<yy>.<mo>.<dd>:<day>

AT-S.Time:<hh>.<mi>.<ss>

<yy>

returns the current date in the format “AT­S.Date:yy.mm.dd:nn” and the current time in the format “AT­S.Time:hh:mm:ss”. The time refers to UTC format and must
be expressed as the time in seconds since 1970-Jan-01.

sets the time as specified by the parameter

value to set the time. The time refers to UTC format and it
must be expressed in seconds since 1970-Jan-01.

Specifies the year

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AT+S.RANDOM

<mo>

<dd>

<day>

<hh>

<mi>

<ss>

6.22 AT+S.RANDOM

Command that provides a random number generated by the peripheral integrated in the STM32.

Usage:

AT+S.RANDOM<cr>

Parameters:

None

Specifies the month

Specifies the day

Specifies the year of the week

Specifies the hours

Specifies the minutes

Specifies the seconds

Result:

AT-S.Number:<value>

<value>

6.23 AT+S.FSC

This command has effect in the RAM memory volume and external SD card volume. The command creates a file
in the selected volume or appends the data following the command in case the file already exists. The space
available in the file system in RAM can be set using ramdisk_memsize configuration variable. Minimum size is 2
Kb, resulting in maximum 2 files.

Usage:

AT+S.FSC=<filename>,<datalen><cr>{data}

Parameters:

<filename>

<datalen>

Specifies the 32-bit random number

name of the file. Max size is 64 bytes

amount of space in bytes to allocate for the file

6.24 AT+S.FSD

The command has effect in the RAM memory volume and external SD card volume. The command deletes an
existing file.

UM2114 - Rev 3

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