RS485 Wiring to An I-Motor

Owned by Marisol Hernandez (Unlicensed)
Last updated: Aug 07, 2024 by Eric Rojas (Unlicensed)
2 min read

All i-Motors have the capability of communicating RS485 to many different RS485 ASCII compatible devices, such as Industrial Computers, Label Makers, etc. Specifically, i-Motors communicate using the 2-wire RS485 protocol and connects to the motor according to the drawing below. A maximum of 32 nodes are supported in one RS485 multidrop as depicted by the RS485 protocol.

 

 

Port E is Pin 5 on the i-Motor 15 Pin I/O connector.
Port F is Pin 6 on the i-Motor 15 Pin I/O connector.
GND is Pin 13 on the i-Motor 15 Pin I/O connector.
All motors are connected in parallel to each other.

In some cases, a biasing resistor is needed to bias the hardware to the receive state. This can typically be done with a 500-Ohm resistor from Port F to GND. Also, if there are long distances between motors, it may be necessary to provide resistance across Port E and F. A 200-Ohm resistor wired from E to F at the remote end of the RS485 line should provide ample biasing.

 

Use the following commands to setup the RS485 port since it is not configured by default.

  1. Open the channel.

OCHN(RS4,1,N,9600,1,8,C)

This will open Ports E and F with RS485 protocol, no parity, 9600 baud*, 1 stop bit, 8 data bits and in command mode**.

  • Only 2400, 4800, 9600, 19200, 38400 baud rates are supported.

** Command and Data mode are possible, but command mode is the only mode that should be used!

  1. Turn off echo for the RS485 channel. Echo must be turned off for proper operation of the RS485 channel.

ECHO_OFF1

The 1 means set this parameter for the RS485 channel.

At this point you can print out this channel with the PRINT1 command or send commands just like a terminal to the i-Motor.

Finally, for addressing information, refer to the Addressing i-Motors FAQ.NOTE: When sending ASCII text to i-Motors always end the transmission with a carriage return and no line feed or the response will be garbled.