RE: CRC issues using Modbus/asyn on 64bit Linux

[Mark Rivers <rivers@cars.uchicago.edu>]

I should add that the CRC is only used on Modbus serial RTU, not on Modbus TCP or Modbus serial ASCII.

So 2 questions:

1) Has anyone successfully run Modbus/asyn serial RTU on 64bit Linux?

2) Has anyone run the Wave P6100 temperature controller with Modbus/asyn serial RTU on any architecture?

Mark


-----Original Message-----
From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-bounces@aps.anl.gov] On Behalf Of Ralph Lange
Sent: Thursday, March 01, 2012 11:30 AM
To: EPICS Tech Talk
Subject: CRC issues using Modbus/asyn on 64bit Linux

Hi,

I am reliably getting CRC errors on the device's answer when reading
more than two parameters (Modbus code 3) through serial RTU on RS-485
from a Wave P6100 temperature controller. The data itself looks good and
reasonable.
One or two word access (Modbus code 1 or 3) seems to work fine.
The IOC runs on 64bit Linux, using Mark Rivers' Modbus on ASYN driver.
(All from synApps 5.5)

Has anyone seen similar behaviour?
Does anyone successfully run Modbus/asyn on 64bit Linux? (To rule out 64
bit issues in the CRC checking part.)

Thanks for any help,
~Ralph