SIM 900R - GSM/GPRS module used in the Wiren Board. Manufactured by SIMCOM.
See the full documentation here:
- Dual Band 900/1800 MHz
- Operates in Russia and CIS countries
- GPRS multi-slot class 10/8 max. 85.6 kbps (downlink)
- Ready-to-use ppp configuration to work as a modem in Linux
- It is possible to control AT-commands (including non-standard ones – for example, remote control via SMS)
POWER KEY and RESET
Modem power can be controlled via two inputs: PWRKEY and RESET.
PWRKEY should be located in the state of logic zero when enabled and the module. Submission on PWRKEY pulse with a duration of not less than a second includes the modem. Resubmitting turns off the modem. When you turn off the modem reports to the port line NORMAL POWER DOWN.
Feeding on the logical unit RESET reboots the module.
== Port speed (Baud Rate)
By default, the module is in Auto-Bauding mode. The port speed is determined automatically after the modem is turned on. In order for the modem to determine the speed, it is necessary to send the symbol "A" preferably for several times.
The module can be set to a fixed port speed mode using THE at+IPR= command (see at-command reference). The port speed settings are stored in the modem's flash memory and stored after power is turned off.
Maximum port speed: 115200. Auto-bauding is guaranteed to work at 38400 speeds but works at 115200 too (sometimes you have to send multiple "A" characters in a row).
Managing the module from Wiren Board interface
Default power settings
AT+CRTXVMA? +CRTXVMA: (0204,01C9,0184,0149,0118,00EF,00CE,00B3,009E,008E,0081,0077,006F,0067,005F,0053),(021A,01B6 ,016D,0131,0105,00E0,00C4,00AE,009B,008C,0080,0078,0071,006A,0065,0053),(023A,01B7,0181,014F,0122,00FC ,00DC,00C1,00AB,009A,008B,007F,0076,0072,006B,0068),(01F4,01AF,0165,012A,00FB,00D7,00BB,00A5,0093,0086 ,007A,0071,006B,0065,0061,005D)