Internet PLC Forum

General => Technical support => Topic started by: acxysty on November 17, 2016, 07:17:05 AM

Title: Priority issues TCP and RS485
Post by: acxysty on November 17, 2016, 07:17:05 AM

Dear all
We are using Nano (great board) at its full capilities, working with both connections TCP (server) and RS port (Master).
Sometimes we have RS response that are not properly handled and we wonder whether this could arised from interrupt priority linked with TCP ?
Thank you in advance
Regards
Thierry

Title: Re:Priority issues TCP and RS485
Post by: support on November 17, 2016, 01:21:48 PM

Is the RS485 port working as a Modbus RTU master?

If the PLC failed to receive a complete response packet from the RTU slave it will usually re-try by resending the packet and get another response. This usually should not be affected by the Modbus TCP server operation. However, if the CPU is kept very busy handling Modbus TCP server activities it is conceivable that the CPU may have less time to handle the serial port.

Also do you know the firmware version of the Nano-10 that you have issue with? You may want to try to update the firmware (if your firmware is >= r83) to see if the performance would improve as there are some recent improvement with the PLC working as a Modbus RTU master.

Title: Re:Priority issues TCP and RS485
Post by: acxysty on November 22, 2016, 08:56:34 AM

Our problem might comes from the OUTCOM commands . Therefore I prefer to start a new post. Regards Thierry