Advantech 3718HG, User Manual

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2 8 PCM-3718H/3718HG User's Manual
BASE+2 (write) - start and stop scan channels
Bit D7 D6 D5 D4 D3 D2 D1 D0
Value CH3 CH2 CH1 CH0 CL3 CL2 CL1 CL0
CH3 to CH0 Stop scan channel number
CL3 to CL0 Start scan channel number
The MUX scan register low nibble, CL3 to CL0, also acts as a pointer
when you program the A/D input range (see previous section). When
you set the MUX start channel to N, the range code written to the
register BASE+1 is for channel N.
Programming example
This C code sets the range for channel 5 to ±0.625 V:
OUTPORTB (BASE+2, 5); /* SET POINTER TO CHANNEL 5*/
OUTPORTB (BASE+1, 3); /* RANGE CODE FOR ±0.625V*/
Note: The MUX start/stop channel changes each time when
you change the input range. Do not forget to reset the
MUX start and stop channels to the correct values
after your range setting.
4.5 Digital I/O Registers - BASE+3/11
The PCM-3718H/3718HG offers two 8-bit digital input/output
channels. These I/O channels use the input or output ports at address-
es Base+3 and BASE+11.