C
Hi all
I've breadboarded the Freeduino running the MCP 23S17 and that works. I also
modified the backplane to 4 slots and installed a header to allow an IDC
connection. I was pondering what to write on the FD to talk to the Linux host.
What I sketched out began to look like a lot of work and Yet Another Duplicative
Protocol (YADP tm.). So I searched and lo and behold, there is a Modbus RTU
slave program for the 'duinos. I may pull it down and see what it gives. The
advantage there is that there is also OSS Linux Modbus RTU master software, so I
wouldn't have to write that either.
> http://sites.google.com/site/jpmzometa/arduino-mbrt/arduino-modbus-slave
This would allow me to produce something useful while waiting on the PLC engine,
a 64 point DIY Modbus RTU slave. The cost should compare very favorablyHi all
I've breadboarded the Freeduino running the MCP 23S17 and that works. I also modified the backplane to 4 slots and installed a header to allow an IDC connection. I was pondering what to write on the FD to talk to the Linux host. What I sketched out began to look like a lot of work and Yet Another Duplicative Protocol (YADP tm.). So I searched and lo and behold, there is a Modbus RTU slave program for the 'duinos. I may pull it down and see what it gives. The advantage there is that there is also OSS Linux Modbus RTU master software, so I wouldn't have to write that either.
> http://sites.google.com/site/jpmzometa/arduino-mbrt/arduino-modbus-slave
This would allow me to produce something useful while waiting on the PLC engine, a 64 point DIY Modbus RTU slave. The cost should compare very favorably with the OTS products :^).
The shrink on the backplane brings the cost for 3 down to $26.50 plus postage. This is doable, so, I'm going to attempt to get it in the 4/19 run. IO cards are still problematic at about twice that for 3, so that may be a while. I think this may play well with the arduino crowd as well as automation types. That's good as it's a larger audience. And less hidebound :^)
Regards
cww
I've breadboarded the Freeduino running the MCP 23S17 and that works. I also
modified the backplane to 4 slots and installed a header to allow an IDC
connection. I was pondering what to write on the FD to talk to the Linux host.
What I sketched out began to look like a lot of work and Yet Another Duplicative
Protocol (YADP tm.). So I searched and lo and behold, there is a Modbus RTU
slave program for the 'duinos. I may pull it down and see what it gives. The
advantage there is that there is also OSS Linux Modbus RTU master software, so I
wouldn't have to write that either.
> http://sites.google.com/site/jpmzometa/arduino-mbrt/arduino-modbus-slave
This would allow me to produce something useful while waiting on the PLC engine,
a 64 point DIY Modbus RTU slave. The cost should compare very favorablyHi all
I've breadboarded the Freeduino running the MCP 23S17 and that works. I also modified the backplane to 4 slots and installed a header to allow an IDC connection. I was pondering what to write on the FD to talk to the Linux host. What I sketched out began to look like a lot of work and Yet Another Duplicative Protocol (YADP tm.). So I searched and lo and behold, there is a Modbus RTU slave program for the 'duinos. I may pull it down and see what it gives. The advantage there is that there is also OSS Linux Modbus RTU master software, so I wouldn't have to write that either.
> http://sites.google.com/site/jpmzometa/arduino-mbrt/arduino-modbus-slave
This would allow me to produce something useful while waiting on the PLC engine, a 64 point DIY Modbus RTU slave. The cost should compare very favorably with the OTS products :^).
The shrink on the backplane brings the cost for 3 down to $26.50 plus postage. This is doable, so, I'm going to attempt to get it in the 4/19 run. IO cards are still problematic at about twice that for 3, so that may be a while. I think this may play well with the arduino crowd as well as automation types. That's good as it's a larger audience. And less hidebound :^)
Regards
cww