This message and any attachments may contain proprietary or confidential information. The IOC runs on 64bit Linux, using Mark Rivers' Modbus on ASYN driver.ĭoes anyone successfully run Modbus/asyn on 64bit Linux? (To rule out 64
#Modbus rtu crc code#
One or two word access (Modbus code 1 or 3) seems to work fine.
#Modbus rtu crc serial#
More than two parameters (Modbus code 3) through serial RTU on RS-485įrom a Wave P6100 temperature controller. I am reliably getting CRC errors on the device's answer when reading Subject: CRC issues using Modbus/asyn on 64bit Linux I should add that the CRC is only used on Modbus serial RTU, not on Modbus TCP or Modbus serial ASCII.ġ) Has anyone successfully run Modbus/asyn serial RTU on 64bit Linux?Ģ) Has anyone run the Wave P6100 temperature controller with Modbus/asyn serial RTU on any architecture? I thought it was probably something wrong in my setup but didn't have time to do much investigation. In my case the IOC was running on vxWorks, but like Ralph I was seeing persistent modbus CRC errors on the IOC console, although the data itself was good.
I've had a similar experience with a chain of West 2300 temperature monitors (also serial RTU on RS-485). To: Mark Rivers 'Ralph Lange' EPICS Tech Talk
#Modbus rtu crc driver#
However, when I originally wrote the driver I did buy some inexpensive Modbus server emulation software, and the driver worked OK including CRC with serial RTU and LRC with serial ASCII.įrom: Emma Shepherd [ Thursday, Ma3:54 PM I don't have any serial RTU devices I can use for testing. But if everyone is getting errors then the problem is likely in my driver. I would like to figure out if this is a problem with bad CRC being generated by the devices, or whether my code is incorrectly computing the CRC on the received message.Ĭan anyone report whether they are using Modbus/asyn with serial RTU without getting CRC error messages? If so, then it would seem like Emma and Ralph have devices that are generating an incorrect CRC. Subject: RE: CRC issues using Modbus/asyn on 64bit Linux
To: Emma Shepherd 'Ralph Lange' EPICS Tech Talk It had CRC bytes swapped! So I modified the modbus driver to accomodate this, also had to add some delays in the asyn interface (again the device's weakness because it did not follow time insertion recommendations from the standard).Īfter that had no CRC errors and it worked.įrom: On Behalf Of Mark Rivers Friday, 2 March 2012 9:13 AM Mark Rivers, Emma Shepherd, "'Ralph Lange'", EPICS Tech Talk Ĭan confirm I have used modbus/asyn without bad CRC generated by a serial RTU.(a neutron radiation monitor BDKN-01), but on 32-bit linux.Īlthough I had to do some changes because the device itself was not in accordance with the standard i.e. RE: CRC issues using Modbus/asyn on 64bit Linux
0 kommentar(er)
