RS232 DF1 CIP Message for SLC500 or Micrologix Channel 0 Change Mode to User

Does anyone have experience with changing the channel 0 mode to user remotely using RS232 communications? I have checked the mode change enable button and can switch from user mode to system mode by sending two bytes to the serial port <ESC>S but when in system mode I believe I need to send a DF1 CIP formatted message instead because <ESC>U does not work. Something like DLE STX <ESC>U DLE ETX CRC but I do not know for sure. I have read the DF1 command set and it provides good examples for switching from run mode to program mode, ect.. but there is no reference to the command used to switch the communications mode on channel 0.

Your help is greatly appreciated.

Thank You,
MW

What I would do is use a serial snooping software and capture the data from RS500 to the controller.
I was looking at changing the baud of the port from the port itself. Nothing Ingram the DF1 manual about that. The job never got that far along I think I had it except for calculating the CRC for the packet.

I agree about your "breed statement" and the command for placing the PLC in user mode must happen along with several other things upon applying the channel configuration because it seems to abort normal communications and goes offline in an abrupt way. You would think this is a standard command but who knows considering the security implications.

If anyone else has used this command to place the PLC channel 0 in user mode via raw RS232 messaging, please let me know.

Thank You,
MW

problem solved

I figured this out using the defined <ESC>U message - only need to match the baud rate correctly. Because I had channel 0 system at 19200 and user at 9600, when I sent the <ESC>S at 9600, it worked but <ESC>U must be sent at 19200 because once you switch to system mode, the baud rate changes. Solved by setting the baud rate the same for both modes.

Hope this makes sense.

MW