GSM GPRS A6 Module

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General Parameters

  • A6 Dimensions 22.8 × 16.8 × 2.5mm;
  • A7 diemsnions: 22.8×19.8×2.5mm;
  • Operating temperature -30 ℃ to + 80 ℃;
  • Operating Voltage 3.3V-4.2V;
  • Power voltage> 3.4V;
  • Standby average current 3ma less;
  • Support for GSM / GPRS four bands, including 850,900,1800,1900MHZ;
  • Support China Mobile and China Unicom's 2G GSM network worldwide;
  • GPRS Class 10;
  • Sensitivity <-105;
  • Support voice calls;
  • Support SMS text messaging;
  • Support GPRS data traffic, the maximum data rate, download 85.6Kbps, upload 42.8Kbps;
  • Supports standard GSM07.07,07.05 AT commands and extended commands Ai-Thinker;
  • It supports two serial ports, a serial port to download an AT command port;
  • AT command supports the standard AT and TCP / IP command interface;
  • Supports digital audio and analog audio support for HR, FR, EFR, AMR speech coding;
  • Support ROHS, FCC, CE, CTA certification;
  • SMT 42PIN

Main Parameters

  • Quad-band 850/900/1800/1900 MHz
  • GPRS multi-slot 12, 1 to 12 may be configured
  • GPRS mobile station Class B
  • Compatible with GSM Phase 2/2 +
  1. Class 4 (2W @ 850/900 MHz)
  2. Class 1 (1W @ 1800 / 1900MHz)
  • Supply voltage 3.3 ~ 4.2V 4.0V typ.
  • Current consumption
  1. 1.3mA @ DRX = 5
  2. 1.2mA @ DRX = 9
  • Operating temperature -30 ° C to +80 ° C
  • Dimensions 22.8 × 16.8 × 2.5mm
  • Weight Approximately 3.0g
  • AT command control standards GSM07.07,07.05 AT commands and extended commands
  • SIM Application Tool Package

Data Transmission

GPRS

  • GPRS Class10 up 85.6 kbps (upstream) & 42.8mbps (downlink)
  • PBCCH support
  • Coding scheme CS 1, 2, 3, 4
  • CSD supports up to 14.4 kbps
  • Support USSD
  • Stack PPP / TCP / UDP / HTTP / FTP / SMTP / MUX

SMS

  • To-point messaging
  • Cell Broadcast messages
  • Text / PDU mode

Voice A speech coding mode:

  • Half Rate (HR)
  • Full Rate (EFR)
  • Enhanced Full Rate (EFR)

AMR:

  • Audio processing mechanism
  • Echo cancellation
  • Echo suppression
  • Noise Suppression

Interface

  • SIM / USIM card 3V / 1.8V
  • UART 2 Ge
  • Analog audio interface
  • 2 channels (1 channel built Class AB audio amplifier)
  • RTC

Certificate

  • CE/ FCC/ RoHS/ CTA

Pin Maps

  • Pin Map A6

  • Pin Map A6

  • updated pins, add extra gpios

  • A7 pin map

  • A7 dimension

  • pin definition

  • support cam

  • A20 Pin Definition

  • A20 Dimension front

  • A20 dimension backside

A6 Pin Definitions

Pin Definition Pin Definition
  • 1 NC Reserved foot
  • 2 NC reserved feet
  • 3 NC Reserved feet
  • 4 NC Reserved feet
  • 5 NC Reserved feet
  • 6 NC Reserved feet
  • 7 NC Reserved feet
  • 8 PWR_KEY power button,> 1.9V more than 2s to boot
  • 9 GPIO1 / INT module for controlling whether to enter a low-power mode
  • high TTL to quit, low to enter, in this standby mode background current <1mA
  • Note that in this mode can not use the serial port
  • 10 UART_CTS / GPIO5 AT serial port CTS pin
  • 11 UART_RTS / GPIO7 AT RTS pin serial port
  • 12 Module hardware RESET pin, this pin is used when the low <0.05V, current 70ma or so
  • NMOS can be used to control; pulled down after the fact is the module hardware shutdown,
  • 13 GND feet
  • 14 SIM_RST SIM card RST pin
  • 15 SIM_CLK SIM card CLK pin
  • 16 VSIM SIM supply pin
  • 17 SIM_DATA SIM data pin
  • 18 GND feet
  • 19 MIC- MIC negative
  • 20 MIC + MIC positive
  • 21 MIC2_P headset MIC interface
  • 22 GND feet
  • 23 EAR_L headset left channel
  • 24 EAR_R headset right channel
  • 25 GND feet
  • 26 REC + horn positive
  • 27 REC- speaker negative
  • 28 GND feet
  • 29 VDD_1V8_OUT Foreign 1.8V supply pins
  • 30 UART_TXD AT serial TXD pin
  • 31 UART_RXD AT serial RXD pin
  • 32 HST_RXD download serial RXD pin
  • 33 HST_TXD download serial TXD pin
  • 34 GND feet
  • 35 GSM_RF foot antenna, the antenna can be connected,
  • if connected to the PCB line, pay attention to the PCB using a 50 ohm trace
  • 36 GND feet
  • 37 NC Reserved foot
  • 38 NC Reserved foot
  • 39 GND feet
  • 40 GND feet
  • 41 VBAT access external power supply pin 3.3V-4.2V, the maximum supply current of not less than 2A
  • 42 VBAT

A20 Pin Definition

Pin Definition Pin Definition
  • 1 CAM_Y1 Camera data pin Y1,
  • 2 CAM_Y2 Camera data pin Y2
  • 3 CAM_Y3 Camera data pin Y3
  • 4 CAM_Y4 Camera data pin Y4
  • 5 CAM_Y5 Camera data pin Y5
  • 6 CAM_Y6 Camera data pin Y6
  • 7 CAM_Y7 Camera data pin Y7
  • 8 PWR_KEY power button,> 1.9V more than 2s to boot; boot after the pin can not be cut off;
  • the foot voltage can be provided only, do not need to consider the power supply.
  • 9 CAM_VSYNC The VSYNC pin of the camera
  • 10 CAM_Y0 Camera data pin Y0
  • 11 CAM_PCLK camera PCLK
  • 12 CAM_CLK Camera master clock
  • 13 CAM_HREF Camera HREF
  • 14 SIM_RST SIM card RST pin
  • 15 SIM_CLK SIM card CLK pin
  • 16 VSIM SIM power supply pin
  • 17 SIM_DATA SIM data pin

This part pin is Wifi

  • 18 WF_IO5 8285 GPIO5
  • 19 VDD3V3 8285 3.3V main power supply
  • 20 WF_RST 8285 RESET
  • 21 WF_RF 8285 RF section
  • 22 WF_TXD 8285 UART0 TXD
  • 23 WF_RXD 8285 UART0 RXD
  • 24 WF_IO12 8285 GPIO12
  • 25 WF_IO13 8285 GPIO13
  • 26 WF_IO15 8285 GPIO15
  • 27 WF_IO2 8285 GPIO2
  • 28 WF_IO0 8285 GPIO0
  • 29 WF_IO4 8285 GPIO4

Above pin is wifi

  • 30 I2C_SDA camera chip I2C data pin
  • 31 I2C_SCL Camera chip I2C clock pin
  • 32 VDD_1V8_OUT external 1.8V power supply pin, then the camera chip 1.8V
  • 33 UART_RXD AT serial port RXD pin, pin level 2.8V
  • 34 UART_TXD AT serial port TXD pin, pin level 2.8V
  • 35 GPIO1 / SLEEP is used to control whether the module enters the low power mode,
  • high level exit, low level entry, in this mode standby current <1mA
  • Note that in this mode the serial port can not be used in this mode phone
  • GPRS data and so can wake up the module.
  • 36 HST_TXD Download the serial port TXD pin, pin level 2.8V
  • 37 HST_RXD Download the serial port RXD pin, pin level 2.8V
  • 38 FLASH_EN Flash control pin, the general need for an external amplifier circuit in order to power LED lights
  • 39 GSM_RF foot antenna, the antenna can be connected,
  • if connected to the PCB line, pay attention to the PCB using a 50 ohm trace
  • 40 GPIO3 General GPIO, in the phone, text messages, data, the module will automatically exit the low-power
  • this pin will out signal, the first high and then pull down.
  • 41 CAM_PDN Camera Power down feet
  • 42 V_CAM The main power supply for the camera
  • 43 CAM_RST Camera RESET pin
  • 44 GND Ground wire
  • 45 VBAT is connected to external power supply pin 3.5V-4.2V, the maximum power supply current is not less than 2A,
  • the pin is GPRS / GSM part of the power supply pin.
  • 46 VBAT

A7 Pin Definitions

Header text Header text
  • 1 NC retention feet,
  • 2 NC reserved feet
  • 3 NC reservations feet, V3 version after hardware GPIO16
  • 4 NC Reserved feet, V3 version after hardware GPIO15
  • 5 NC reservations feet, V3 version after hardware GPIO14
  • 6 NC Reserved feet, V3 version after hardware GPIO6, (used as an internal network status indicator)
  • 7 NC reservations feet, V3 version after hardware GPIO3
  • 8 PWR_KEY power button,> 1.9V more than 2s to boot; boot after the broken foot can continue to develop;
  • 9 GPIO1 / INT module for controlling whether to enter a low-power mode
  • high TTL to quit, low to enter, in this standby mode background current <1mA
  • Note that in this mode can not use the serial port
  • 10 UART_CTS / GPIO5 AT serial port CTS pin
  • 11 UART_RTS / GPIO7 AT RTS pin serial port
  • 12 Module hardware RESET pin, this pin is used when the low <0.05V, current 70ma or so
  • NMOS can be used to control; pulled down after the fact is the module hardware shutdown,
  • The foot in the normal working mode can not have leakage, otherwise it will lead to unstable modules, it is difficult to register the network;
  • Note that when the RESET pin PWR_KEY first pull low, and then pulled high.
  • 13 GND feet
  • 14 SIM_RST SIM card RST pin
  • 15 SIM_CLK SIM card CLK pin
  • 16 VSIM SIM supply pin
  • 17 SIM_DATA SIM data pin
  • 18 GND feet
  • 19 MIC- MIC negative
  • 20 MIC + MIC positive
  • 21 MIC2_P headset MIC interface
  • 22 GND feet
  • 23 EAR_L headset left channel
  • 24 EAR_R headset right channel
  • 25 GND feet
  • 26 REC + horn positive
  • 27 REC- speaker negative
  • 28 GND feet
  • 29 VDD_1V8_OUT Foreign 1.8V supply pins
  • 30 UART_TXD AT serial TXD pin, pin 2.8V
  • 31 UART_RXD AT serial RXD pin, pin 2.8V
  • 32 HST_RXD download serial RXD pin, pin 2.8V
  • 33 HST_TXD download serial TXD pin, pin 2.8V
  • 34 GND feet
  • 35 GSM_RF foot antenna, the antenna can be connected,
  • if connected to the PCB line, pay attention to the PCB using a 50 ohm trace
  • 36 GND feet
  • 37 NC Reserved foot
  • 38 NC Reserved foot
  • 39 GND feet
  • 40 GND feet
  • 41 VBAT access external power supply pin 3.5V-4.2V, the maximum supply current of not less than 2A
  • 42 VBAT

A6C Pin definitions

  • Camera interface supports only 30-megapixel fixed-focus camera, the chip can be used include OV7670, GC0308, GC0328, GC0309
Header text Header text
  • 1 Data foot Y1 CAM_D1 camera
  • 2 Data foot Y2 CAM_D2 camera
  • 3 Data foot Y3 CAM_D3 camera
  • 4 Data pin Y4 CAM_D4 camera
  • 5 Data foot Y5 CAM_D5 camera
  • 6 Data foot Y6 CAM_D6 camera
  • 7 Data foot Y7 CAM_D7 camera
  • 8 PWR_KEY power button,> 1.9V more than 2s to boot; boot after the broken foot can continue to develop;
  • 9 GPIO1 / INT module for controlling whether to enter a low-power mode
  • high TTL to quit, low to enter, in this standby mode background current <1mA
  • Note that in this mode can not use the serial port
  • 10 UART_CTS / GPIO5 AT serial port CTS pin
  • 11 UART_RTS / GPIO7 AT RTS pin serial port
  • 12 Module hardware RESET pin, this pin is used when the low <0.05V, current 70ma or so
  • NMOS can be used to control; pulled down after the fact is the module hardware shutdown,
  • The foot in the normal working mode can not have leakage, otherwise it will lead to unstable modules, it is difficult to register the network;
  • Note that when the RESET pin PWR_KEY first pull low, and then pulled high.
  • 13 GND feet
  • 14 SIM_RST SIM card RST pin
  • 15 SIM_CLK SIM card CLK pin
  • 16 VSIM SIM supply pin
  • 17 SIM_DATA SIM data pin
  • 18 CAM_RST camera RESET pin
  • 19 MIC- MIC negative
  • 20 MIC + MIC positive
  • 21 CAM_CLK camera master clock
  • 22 CAM_PCLK camera PCLK
  • 23 I2C_SDA camera chip I2C data pins
  • 24 I2C_SCL camera chip I2C clock pin
  • 25 CAM_VSYNC camera VSYNC
  • 26 CAM_PDN Camera Power down leg
  • 27 CAM_HREF camera HREF
  • 28 Data foot Y0 CAM_D0 camera
  • 29 VDD_1V8_OUT Foreign 1.8V supply pins, then the camera chip 1.8V
  • 30 UART_TXD AT serial TXD pin, pin 2.8V
  • 31 UART_RXD AT serial RXD pin, pin 2.8V
  • 32 HST_RXD download serial RXD pin, pin 2.8V
  • 33 HST_TXD download serial TXD pin, pin 2.8V
  • 34 GND feet
  • 35 GSM_RF foot antenna, the antenna can be connected,
  • if connected to the PCB line, pay attention to the PCB using a 50 ohm trace
  • 36 GND feet
  • 37 GPIO3 ordinary GPIO
  • 38 FLASH_EN flash control pin, generally require an external amplifier to power the LED lights
  • The main power supply 39 V_CAM camera
  • 40 GND feet
  • 41 VBAT access external power supply pin 3.5V-4.2V, the maximum supply current of not less than 2A
  • 42 VBAT

Quick Start Guide

  • Refer to development board
    A7 setup.png

A6

  • See the demo video.
  • Use Mini Development board, connect VIN, GND, RX and TX, optinally add microUSB power and GSM antenna if the board failed on make calls later
  • Connect PWR_KEY to VCC for more than 2 seconds
  • Open serial monitor set rate 115200, send commands "AT" return "OK"
  • Maybe some extra message info:
+CIEV: "MESSAGE",1
+CMT: ,156
0891683110606605F06005800110F00008614011516372238C050003E70202621670B951FB8FDB51650068007400740070003A002F002F007700610070002E00310030003000310030002E0063006F006D002067E58BE28BE660C53002000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

+CIEV: "MESSAGE",1
+CMT: ,156
0891683110606605F06405800110F00008614011516372238C050003E702016E2999A863D0793AFF1A622A6B620030003467080031003065E50032003465F6FF0C60A85F5367087D2F8BA14F7F75286D4191CF0030002E0030004D0042300251764E2DFF0C770151856D4191CF5DF24F7F75280030002E0030004D0042FF0C52694F59003300300030002E0030004D0042FF1B002056DE590D201C6D4191CF67E58BE2201D
  • Or similar like
^CINIT: 1, 0, 0
^CINIT: 1, 0, 0
+CREG: 0
+CREG: 3
  • Making phone call, in which 18576608994 is the phone number, and use ATH to hang off the phone call:
ATD18576608994;

A6C Camera

Added AT:

  • AT + CAMSTART = N, N from 0-2, N represents the operating mode, 0 QVGA, 1 -VGA, 2-QQVGA
  • AT + CAMCAP, take pictures, the default picture format is JPG
  • AT + CAMRD, read the contents of the photo is JPG file format
  • AT + CAMSTOP, turn off the camera

A7 GPS

Instructions: Increased include AT

  • AT + GPS = 1 Open GPS
  • AT + GPS = 0 Close GPS
  • AT + AGPS = 1 Open AGPS
  • AT + AGPS = 0 Close AGPS
  • After opening the GPS / AGPS, NEMA default information from GPS_TXD pin output to 9600 baud, if you want NEMA
  • From AT serial output, you can use AT + GPSRD.
  • AT + GPSRD = 0 Close NEMA output port from the AT
  • AT + GPSRD = N NEMA information from AT N seconds once the output port, the actual use of the N into digital;

Other AT commands examples

^CINIT: 2, 32, 41891
^CINIT: 1, 0, 0
^CINIT: 8, 6144, 1
^CINIT: 16, 0, 1638450
^CINIT: 32, 0, 0
+CREG: 0
+CTZV:16/07/06,11:33:25,+08
+CREG: 5
 
ati                     //check version, manufacturer info
Ai Thinker Co.LTD
A6 
V03.03.20160710006H03
OK
 
at+ccid   //check ccid to see if has sim card
+SCID: SIM Card ID: 898602#4221620070426
OK
 
at+creg?  //check if network register 
+CREG: 1,5
OK
 
at+csq    //check signal
+CSQ: 31,99
OK
 
at+cgatt=1          // attached network
+CTZV:16/07/06,11:34:17,+08
OK
 
at+cgdcont=1,"IP","cmnet"   //set pdp parameter
OK
 
at+cgact=1,1                 //active this pdp
OK
 
at+cipstatus?               //check ip connection, should have 8 channels, maxium support 4 channels of tcpip
+CIPSTATUS:0,IP GPRSACT  
1,IP INITIAL  
2,IP INITIAL  
3,IP INITIAL  
4,IP INITIAL  
5,IP INITIAL  
6,IP INITIAL  
7,IP INITIAL  
OK
 
at+cipstart="TCP","121.41.97.28",60000   //connect to server 
CONNECT OK
OK
 
at+cipsend=5,qwert    //send 5 bytes, note only support visible characters in this way
OK
 
at+cipsend=5          //send 5 bytes, send any kind in binary data this way
> ��������
OK
 
at+cipsend           //send characters, end up with CTRL+Z(hex = 0x1a)
> qwert
�
OK
+CIPRCV:4,test      //receive data 4 bytes from server, content is "test", could be binary data also
 
at+cipstatus?       //插叙? insert show ip link status
+CIPSTATUS:0,CONNECT OK  
1,IP INITIAL  
2,IP INITIAL  
3,IP INITIAL  
4,IP INITIAL  
5,IP INITIAL  
6,IP INITIAL  
7,IP INITIAL  
OK
 
at+cipclose   //close the link
OK
 
at+cipmux?    //enquiry if multiple link opened查询是否开启多连接
+CIPMUX:0   
OK
 
at+cipmux=1   //turn on multiple link
OK
 
at+cipstart="TCP","121.41.97.28",60000  //send first TCP connection 
+CIPNUM:0                              //only return this when multiple link activated, 0 is the returned link number 
CONNECT OK
OK
 
at+cipstart="TCP","121.41.97.28",60001  //send 2nd TCP connection 
+CIPNUM:1                              //only return this when multiple link activated, 1 is the returned link number 
CONNECT OK
OK
 
at+cipstart="TCP","121.41.97.28",60003 //send 3th TCP connection 
COMMAND NO RESPONSE!                  //command over time, since the server did not open this port
 
at+cipstatus?                  
+CIPSTATUS:0,CONNECT OK  
1,CONNECT OK  
2,TCP/UDP CONNECTING  
3,IP INITIAL  
4,IP INITIAL  
5,IP INITIAL  
6,IP INITIAL  
7,IP INITIAL  
OK
 
at+cipclose=3                    //close the connection of link number 3 
+CME ERROR:50                    //return error because link no 3. is not established 
 
at+cipclose=2                    //close the connection of link number 2
OK
 
at+cipstart="TCP","121.41.97.28",60002  //set up new connection
+CIPNUM:2
CONNECT OK
OK
 
at+cipstart="UDP","121.41.97.28",60006  //setup new udp connection
+CIPNUM:3
UDP BIND OK
OK
 
at+cipstatus?
+CIPSTATUS:0,CONNECT OK            //can see 0-3 connection are occupied, setup 4 ip connections 
1,CONNECT OK  
2,CONNECT OK  
3,BIND OK  
4,IP INITIAL  
5,IP INITIAL  
6,IP INITIAL  
7,IP INITIAL  
OK
 
at+cipsend=0,5,qwert       //link 0 send 5 bytes data “qwert”，this command only support visible data
OK
+CIPRCV:0,4,test           //link 0 receive server data: “test”，this command support any kind of data
 
at+cipclose=2              //close link 0
OK
 
at+cipstatus?             //check link info 
+CIPSTATUS:0,CONNECT OK  
1,CONNECT OK  
2,IP CLOSE  
3,BIND OK  
4,IP INITIAL  
5,IP INITIAL  
6,IP INITIAL  
7,IP INITIAL  
OK
 
at+ciphcfg?              //check heartbeat config
+CIPHCFG:0,10,00,00
1,10,00,00
2,10,00,00
3,10,00,00
4,10,00,00
5,10,00,00
6,10,00,00
7,10,00,00
OK
 
at+ciphcfg=0,1,112233         //set link 0 heartbeat packet  hex: 0x11，0x22，0x33
OK
 
at+ciphcfg?                
+CIPHCFG:0,10,112233,00
1,10,00,00
2,10,00,00
3,10,00,00
4,10,00,00
5,10,00,00
6,10,00,00
7,10,00,00
OK
 
at+ciphmode=0,1     //turn on link 0 heartbeat packet
OK
 
at+cipsend=3,5,qwert    //link 3 send 5 bytes:“qwert”
OK
 
at+cipclose=3     //close link 3
OK
+TCPCLOSED:1    //server close link 1
OK
 
at+cipstatus?
+CIPSTATUS:0,CONNECT OK  
1,IP CLOSE  
2,IP CLOSE  
3,IP CLOSE  
4,IP INITIAL  
5,IP INITIAL  
6,IP INITIAL  
7,IP INITIAL  
OK
+TCPCLOSED:0    //server close link 0 
OK
 
at+cipstatus?
+CIPSTATUS:0,IP CLOSE  
1,IP CLOSE  
2,IP CLOSE  
3,IP CLOSE  
4,IP INITIAL  
5,IP INITIAL  
6,IP INITIAL  
7,IP INITIAL  
OK

A6 Module

  • Connect USB cable and make sure 2A current can be supplied
  • Connect any USB-TTL breakout tool, RXD, TXD and GND
  • Press Boot button the module will be powered up.
  • Turn on serial monitor to send test commands like "AT"

  • Board usage

  • breakout board pin list

  • Example.jpg

    Caption2

A20 Module

A20 is a GPRS and Wifi Combo module, also supports plug-Camera, Wifi chips with espressif's ESP8285. A20 GPRS part and WIFI part can be separated from a separate power supply, work alone, without disturbing each other. The A20 supports the following modes of operation:

  • 1. Separate GPRS mode: In this mode, the user only needs to power on the GPRS alone, and the MCU can control the GPRS part through the serial port.
  • 2. Separate WIFI mode: In this mode, the user only needs to power on the WIFI part, and use the MCU to control the WIFI part through the serial port.
  • 3. GPRS + WIFI mode: In this mode, the user can use two serial ports to control the GPRS part and WIIF part respectively.
  • 4. WIFI master MCU, control GPRS mode: In this mode, the user uses the ESP8285 part of the WIFI as the master, to control the GPRS part, because WIFI is only a two-way serial port, this time the user needs to develop ESP8285 side program;

A20 Breakout

A20 Breakout.jpg
  • Toggle 1,3 - GPRS uart port to Pin header,
  • Toggle 2,4 - ESP8285 secondary uart port IO13, IO15 to GPRS uart port
  • Toggle 5,6 - ESP8285 secondary uart port IO13, IO15 to Pin header

Note of this the breakout board

  • DIP switch mark 1 2 3 4 5 6 should be reversed, so if you look on the number mark
toggle 4,6 - turn on GPRS to pin U_TXD and U_RXD
toggle 3,5 - connect  GPRS uart pin to ESP8285 secondary uart port IO13, IO15
toggle 1,2 - Pin header to ESP8285 secondary uart port IO13, IO15
  • Wifi Uart pin WRXD, WTXD can always be used, regardless dip switch.
  • USB for power ONLY, not for data

Design Note

  • The maximum output current of the power supply can not be lower than 2A, otherwise it will be unstable, causing the module to restart;
  • Antenna as a result of power, SIM card, serial port will affect the position on the PCB as far as possible, and the best not to the same side of the PCB, if you go 4 layer board, you can string the serial port shielding;
  • AT serial port rate is 15200, enter the AT command to \ r \ n end;
  • After boot, at to determine whether the module boot, 
at + ccid used to determine whether the inserted card or SIM correctly identified to,
at + csq used to query the network signal, generally more than 2, 
at + creg? Used to query the network registration 1,1 is a local registration, 1,5 is roaming registration;

Documents

Core board schematic

  • A6

  • A6 R2 schematic, auto start pwr_key, etc

  • A7

  • A6C

  • A20

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