Advantech PCI-1755, User Manual

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M2, M1 and M0 Select operation mode
M2
M1 M0 Mode Description
0 0 0 0 Stop on terminal count
0 0 1 1 Programmable one shot
X 1 0 2 Rate generator
X 1 1 3 Square wave rate generator
1 0 0 4 Software triggered strobe
1 0 1 5 Hardware triggered strobe
BCD Select binary or BCD countering.
BCD Type
0 Binary counting 16-bits
1 Binary coded decimal (BCD) counting
If you set the module for binary counting, the count can be any number from 0 up to 65535.
If you set it for BCD (Binary Coded Decimal) counting, the count can be any number from
0 to 9999.
If you set both SC1 and SC0 bits to 1, the counter control register is in read-back command
mode. The control register data format then becomes:
BASE+2CH 82C54 control bit, read-back mode
Bit D7 D6 D5 D4 D3 D2 D1 D0
Value 1 1 CNT STA C2 C1 C0 X
CNT=0 Latch count of selected counter(s)
STA=0 Latch status of selected counter(s)
C2, C1&C0 Select counter for a read-back operation
C2 = 1 select Counter 2
C1 = 1 select Counter 1
C0 = 1 select Counter 0
If you set both SC1 and SC0 to 1 and STA to 0, the register selected by C2 to C0 contains a
byte which shows the status of the counter. The data format of the counter read/write
register then becomes: