Author Topic: serial communication problem  (Read 12949 times)

Bill

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serial communication problem
« on: September 19, 2006, 03:43:33 PM »
I am having a problem with communication loss between my maple systems 520M and the T100MD1616+ plc.

The loss of communications is for about 3-5 seconds and happens with the touch screen configured RS485 or RS232.  The protocol is modbus.

Comms on the HMI are set to match the plc's defaults. The hmi is sending it's request every 3 seconds and I have confirmed this using hyperterminal.  All power cables are routed seperate from comms cables.

All relay coils are snubbed and all cables are shielded with shields terminated to a common ground.

support

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Re:serial communication problem
« Reply #1 on: September 19, 2006, 06:30:49 PM »
Try changing the comm delay parameter in Maple System HMI to 0. We believe there is a problem with the Maple MODBUS driver when using delay other than zero.
Email: support@triplc.com
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Dogface

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Re:serial communication problem
« Reply #2 on: April 13, 2007, 08:09:38 PM »
I was having a smiliar problem with my Maple systems OIT.  I found that setting the comm port to the specific protocol, that the problem went away.

Setprotocol 1, 1 in my case.  Hope this helps.

Dogface