Modbus and serial printer

[AlanH]

  Hi have a Jazz application where I was hoping to use a MJ20-RS4 with 1 output driving a couple of scales via modbus/RS485 and the 2nd output to drive a serial printer via RS232. Both outputs appear to work fine if I use them separately however every time I poll the scales via modbus I appear to also be sending a character or character group to the printer which is being interpreted as an = . After 80 characters (I think) hit the printer it prints a line of ='s. I only need to print out about 10 lines of text from the printer over a half hour batch whereas the modbus is updating at a few Hz. I can't think of a solution to isolating the 2 ports communications from each other. If necessary I could fiddle with baud rates when I need to swap between devices but that may generate an issue with weird characters being interpreted by the printer. I can't appear to clear the printers cache as it requires an ascii control c code to be sent and it doesn't look like I can put that into a SMS message.

  Any ideas on how I can stop the extraneous ='s would be great.

 

Thanks in advance.