Change COM Port Parameters

This Special Function, 310, enables you to change the serial communication port default settings for M91 controllers. M90 models do not support this function.

In Jazz controllers, use Function 310 to modify the default settings of an Add-on Port.

Since there are no Ladder elements for Special Functions, you perform them by storing values into SIs in accordance with the tables and figures shown below.

Configuration Parameters

After the parameters below have been stored into the appropriate SIs, initialize the COM port by storing 310 into SI 140.

SB 141 indicates whether the COM port has been successfully initialized with the new parameters successfully: 1 = success, 0 =fail.

Parameter

Store to SI

M91

Jazz: MJ20-RS

Jazz: MJ20-PRG

Baud Rate

141

Legal Baud rates
Store value into SI 141 to set baud rate.

 

 

  • 110

  • 300

  • 600

  • 1200

  • 2400

  • 4800

  • 9600

  • 19200

  • 38400 (store 384)

  • 57600 (store 576)

  • 300

  • 600

  • 1200

  • 2400

  • 4800

  • 9600

  • 19200

  • 300

  • 600

  • 1200

  • 2400

  • 4800

  • 9600

Data bits

142

  • 7

  • 8

Parity

143

  • 0=even

  • 1=odd

  • 2=none

Hardware Flow Control

144

  • 0=No Flow Control

  • 1=Flow Control

RS232:

  • 0=No Flow Control

  • 1=Flow Control

  • 2=enable RS485 and RS232

Note that in order to implement RS485, you must write 2 to SI144

Always write 0

Time out

145

Time out units:

10 msecs; a Time out value of 100 is equal to 1 second. Legal values:

  • 50

  • 100

  • 150

  • 200

  • 500

  • 6000

Stop bits

146

  • 1

  • 2

2 stop bits is not supported

COM Init

140

This must be the final parameter stored.

Storing the value 310 into SI 140 initializes the COM port with the new parameters.