Rockwell Automation 1746-HSCE2 Multi-Channel High Speed Counter Module - Manual (Page 86)

Publication 1746-UM002B-EN-P - August 2004
5-4 Start Up, Operation, Troubleshooting, and Debug Mode
Application Errors
The module can encounter the following application errors.
Linear Counter Overflow/Underflow
When the maximum count would be exceeded, the counter overflow
bit in the counter status byte is set.
When the count would become one lower than the minimum count,
the count underflow bit in the counter status byte is set.
When the module is in overflow condition, the programmed
maximum count value is reported and ranges that include the value
will still be acted upon. Likewise, in underflow condition, the
minimum count value is reported, and ranges including it are affected.
Rate Overflow/Underflow
The rate overflow bit is set when the rate is more than the maximum
rate value.
Min./Max.
Rate Value
• Counter number bits are not set to a valid number.
(Operating Mode may be incorrect.)
• The minimum rate is outside its valid range.
• The maximum rate is outside its valid range.
• The maximum rate is less than or equal to the Minimum Rate.
• Programmed output rate ranges are outside the boundaries of
the new minimum/maximum rate values.
• Rate values may be in the wrong format.
Program
Ranges • The counter number bits are not set to a valid number.
(Operating mode may be incorrect.)
• The range number is greater than the programmed range
allocation value
• The range start value is outside its valid range.
• The range stop value is outside its valid range.
• Range values may be in the wrong format.
Counter
Control
• The soft preset bit is set while in No Preset mode.
• The internal direction bit is set while not in the internal
direction mode.
• A counter that is not valid in the selected mode has its enable
counter bit set.
Table 5.1 Error Conditions by Programming Block
Programming
Block Error Conditions