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General => Technical support => Topic started by: Mike_PAC on November 17, 2004, 09:06:46 AM

Title: RS485 - Rs232 Communication
Post by: Mike_PAC on November 17, 2004, 09:06:46 AM
 I am using your T100MD888 to communicate to a operator display. I need to send ASCII characters to this display.  The display operates as a display only, not to communicate back to the Tri-PLC.
 I am using the RS485 port with the Tri-PLC RS232-RS485 converter.
The operator display has a fixed baud rate of 1200, with no handshaking required. The operator display is set for RS232 levels, and uses "2" start bits, 1 Stop bit, 8 Data bits and no parity.
I wired the RS232/RS485 Tri-Plc converter using pins 3 and 5.
 I have a custom function triggered from the 1st scan bit to set the buad rate on port #3
 ie; Setbaud 3, &H0F

I have another custom function that is triggered with a pushbutton input to send out a single character to the operator display.
 ie; Print #3 "A"

I get the Red LED on the RS232/RS485 to flash each time when the function is called but no data on the display.

What am I doing wrong?
 
 
Title: Re:RS485 - Rs232 Communication
Post by: support on November 17, 2004, 10:32:12 AM
The Auto485 pin 2 is the transmit pin to the external device. So you should try pin 2 and pin 5.
Title: Re:RS485 - Rs232 Communication
Post by: Mike_PAC on November 17, 2004, 08:12:15 PM
 Thanks! That fixed it! .. I must have had Brain Fade!!!!!!