Hello,
I start this post based on a simple problem: communication between some devices and WinCC over Modbus RTU network (protocol).
Believe it or not WinCC (V6.2) does not "know" Modbus! I find this very intriguing: a big name with a big SCADA doesn't know the alphabet...Anyway, on Siemens support website is this link that sends us to search for Modbus driver provided by another (and presumable concurrent) "manufacturer" www.allmendinger.de where we can find the driver (here) - proprity of this guy, Jörg Allmendinger, for a very "fair" price - around 500 Euros.
I have 3 questins in my mind:
1. is this guy a former (current) Siemens employee (and they split earnings
)?
2. why Siemens discontinued the Modbus drivers starting with WinCC v6?
3. why a Modbus driver is so expensive if the Modbus protocol is free?
Besides this short history I want to know if there are some free/cheap Modbus OPC Servers?
I'm thinking to write my own driver for Modbus in WinCC...(how hard can it be? )
I start this post based on a simple problem: communication between some devices and WinCC over Modbus RTU network (protocol).
Believe it or not WinCC (V6.2) does not "know" Modbus! I find this very intriguing: a big name with a big SCADA doesn't know the alphabet...Anyway, on Siemens support website is this link that sends us to search for Modbus driver provided by another (and presumable concurrent) "manufacturer" www.allmendinger.de where we can find the driver (here) - proprity of this guy, Jörg Allmendinger, for a very "fair" price - around 500 Euros.
I have 3 questins in my mind:
1. is this guy a former (current) Siemens employee (and they split earnings
)? 2. why Siemens discontinued the Modbus drivers starting with WinCC v6?
3. why a Modbus driver is so expensive if the Modbus protocol is free?
Besides this short history I want to know if there are some free/cheap Modbus OPC Servers?
I'm thinking to write my own driver for Modbus in WinCC...(how hard can it be?
)