Machsupport Forum

Mach Discussion => Mach4 General Discussion => Topic started by: maroskoxx@gmail.com on March 03, 2023, 01:28:51 AM

Title: Mach4 modbus issue
Post by: maroskoxx@gmail.com on March 03, 2023, 01:28:51 AM

Im trying to migrate working vfd modbus control from mach3 to mach4. However if I use the same register numbers, some get “Illegal data address exception response”
Read registers work fine. Write registers have this issue.
Im using Delta VFD-E. Troublesome registers are 2000H(control) and 2001H (frequency) (8192 and 8193)

Title: Re: Mach4 modbus issue
Post by: joeaverage on March 03, 2023, 03:22:35 PM

Hi,
there was/is a current thread which has an idea that you should investigate:

https://www.machsupport.com/forum/index.php?topic=47113.0 (https://www.machsupport.com/forum/index.php?topic=47113.0)

It concerns register addressing. Some installations number the registers 0,1,2,3......8192......etc whereas some others number them 1,2,3.....8192....etc.
There is a setting in the Mach4 Modbus plugin which allows you to select either protocol.

Craig

Title: Re: Mach4 modbus issue
Post by: maroskoxx@gmail.com on March 05, 2023, 09:12:24 AM

Thank you very much, it worked. im just going to mention, that it’s useful to restart mach4 between some modbus configuration changes.