ICS ELECTRONICS 4807, Instruction Manual

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5-6
5
TABLE 5-2 TROUBLESHOOTING GUIDE
CONTINUED
Possible
Symptom Fault Action or Check
Unit fails to respond No delay after an Provide a 70 ms minimum
or responds wrong the address or delay after changing an
after an address change address mode address or address mode
or after an address change setting.
mode change
Insufficient delay Program running on faster CPU
or in a compiled form runs
faster. Change delay routine to
a called time function that
tests the CPU clock.
Byte Data transfer fails Wrong command or Start with short form
command syntax commands: BIn? or BOn data.
i.e. BI1? or BO2 85 (55 HEX)
Wrong output value Format setting BOn commands use decimal
format.
PO command uses the
format set by the FORMat
command. Check the FORMat
command setting.
Wrong input data Format setting PI?, BI? and BIn? queries use
value the format set by the FORMat
command. Check the FORMat
command setting.
Translation Table If TABLE format selected,
values check table values.
Data output did not Output command Data polarity takes place
respond to a polarity not sent with next output command.
command Write a new value to the output
port.
For configured ports Configure ports as inputs or
Polarity command outputs before assigning
out of sequence polarity.