Specifications

Smart Machine Smart Decision
SIM900_AT Commands Manual_V1.07 157 2012.12.10
<GPIO> The GPIO you want to be set. (It has relations with the
hardware, please refer to the hardware manual)
<function> Only when <Operation> is set to 0, this option takes
effect.
0 Set the GPIO to input.
1 Set the GPIO to output
2 Set the GPIO to keypad
<level> 0 Set the GPIO low level
1 Set the GPIO high level
Reference Note
Only GPIO1, GPIO2, GPIO3, GPIO4, GPIO6, GPIO7, GPIO8, GPIO9 can
b
e used as Keypad. And if one of them is set to gpio function, others will
be set to GPIO output and low level automatically.
6.2.46 AT+SPWM Generate the Pulse-Width-Modulation
AT+SPWM Generate the Pulse-Width-Modulation
Response
+SPWM: (list of supported <index>s),(list of supported <period>s),(list of
supported <level>s)
OK
Test Command
AT+SPWM=?
Parameters
See Write Command
Response
OK
If error is related to ME functionality:
+CME ERROR: <err>
Write Command
AT+SPWM=<in
dex>,<period>,
<level>
Parameters
<index> Integer type: the index number of PWM port, which value is
0-2;
0: for buzzer (according to the hardware support or not).
1: corresponding to PWM_OUT0 in the hardware circuit
2: corresponding to PWM_OUT1 in the hardware circuit
<period> The range of <period> is 0-126 if <index> is set to 1 or 2,
the range of <period> is 0-65535 if <index> is set to 0,
the output frequency equals to (26MHz/8)/(period+1).
<level> 0-100: tone level, which can be converted to duty ratio.
Reference Note
z We have a 26MHz crystal oscillator. The MAX frequency of PWM is
26/8=3.25Mhz.
z The equation of final frequency and <period> is this: