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Technical support / DM wiping when reading from EEPROM
« on: December 17, 2010, 04:46:17 PM »
I'm interfacing with a T100M over serial coms, using multi-point protocol commands. When reading EEPROM integer data (RXI...), sometimes timeouts occur at the PLC and this appears to correspond with timer based operations on the PLC. the problem gets worse as it also causes the DM to be wiped.
I'm flying blind on this as I don't have the PLC's code; everything is based on external observations so any input would be most welcome. I've observed that one timer appears to reset when this timeout occurs. What's even more interesting is I can only get it to do that when reading more than 16 words at a time. If it is Hex 20, (32 words), the timeouts when they occur will correspond with one of the timers restarting and the DM being wiped. If I only use Hex 10 words, timeouts are benign.
What could cause this conflict ?
Thanks
I'm flying blind on this as I don't have the PLC's code; everything is based on external observations so any input would be most welcome. I've observed that one timer appears to reset when this timeout occurs. What's even more interesting is I can only get it to do that when reading more than 16 words at a time. If it is Hex 20, (32 words), the timeouts when they occur will correspond with one of the timers restarting and the DM being wiped. If I only use Hex 10 words, timeouts are benign.
What could cause this conflict ?
Thanks