Measurement Computing CB-7000 DIO - Manual (Page 59)

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CB-7000 DIO Manual
Command, such as @AA(Data) or #AABBDD, the module
ignores the command and returns ‘!’, and will not change the out-
put to the output command value. The host watchdog timeout
status is set and stored in EEPROM when the host watchdog
timeout interval expired, and only can be cleared by Command
~AA1. If user wants to change the output, he first needs to clear the
host watchdog timeout status, then send an output command to
change the output to a desired value.
2. PowerOn Value. When the Module Watchdog Timer is
set, and the host watchdog timeout status is clear, the module’s
output is set to the predefined PowerOn Value.
3. Output Command value. If the host watchdog timeout
status is clear, the user issues a digital output command such as
@AA(Data) or #AABBDD to the module for changing the output
value. The module will respond successful (receive >).
3.6 Latched Digital Inputs
If, for example, the user connects a PB switch to a a digital
I/O module input channel and wants to read the switch stoke. The
input is a pulse digial input, and user will lose the data. When read
by Command $AA6 in A or B position, the re-
sponse is that no input occurred and he will lose
the pulse information. However, the read latch-low digital input
Command $AAL0 will solve this problem. When $AAL0 Com-
mand in A and B position is issued, the response indicates that there
was a low pulse between A and B position for a switch closure.