Overview:   
             
         1. The A9 development board is a multi-function development board based on the Axin A9G GPRS/GSM module, which can be used to verify the basic communication functions and peripheral functions of the A9 module.   
         2. A9 development board has basic telephone/sms, GPRS network communication.   
         3. A9 development board contains lithium battery charge management, microphone, speaker interface, USB communication interface, multiple user buttons / led, TF card slot, acceleration sensor, SPI interface, I2C2 interface, ADC interface.   
         4. Pudding series development board camera expansion board, can be connected to 30W/200W camera.   
         5. A9 development board slot machine expansion board, can be connected to a traditional coin machine.   
             
         Specifications:   
             
          * Chip size: 19.2*18.8*2.7mm (±0.2mm)   
          * Working temperature -30 ° C +80 ° C;   
          * Working voltage is 3.5V-4.2V, 4V power supply is recommended;   
          * Boot voltage > 3.5V;   
          * Low power average current is below 2ma;   
          * Support GSM/GPRS four frequency bands, including 850, 900, 1800, 1900MHZ;   
          * GPRS Class 10;   
          * Sensitivity <-105;   
          * Support voice calls;   
          * Support SMS SMS;   
          * GPIO level is 2.8V;   
          * Support GPRS data service, maximum data rate, download 85.6Kbps, upload 42.8Kbps;   
          * Support standard GSM07.07, 07.05 AT commands and Ai-Thinker extension commands;   
          * A9 supports 3 serial ports, one download serial port and one AT command port;   
          * AT command supports standard AT and TCP/IP command ports;   
          * Support digital audio and analog audio, support HR, FR, EFR, AMR voice coding    
     
     Package Included:    
     
 1 x A9 Core Board Pudding Development board     
      
     
     Document:    
     
        For other basic information, please refer to the WIKI/GPRS page.                         :