Intel MB820 user manual JP1 RS232/422/485 COM2 Selection, JP2 COM1 RS232 +5V/+12V Power Setting

INSTALLATIONS

JP1: RS232/422/485 (COM2) Selection

COM1 is fixed for RS-232 use only.

J3, COM2 is selectable for RS232, RS-422 and RS-485.

The following table describes the jumper settings for COM2 selection.

COM2	RS-232	RS-422	RS-485
Function
	Short:	Short:	Short:
	1-2	3-4	5-6
Jumper	9-11	7-9	7-9
Setting	10-12	8-10	8-10
(pin closed)	15-17	13-15	13-15
	16-18	14-16	14-16

JP2: COM1 RS232 +5V/+12V Power Setting
JP2	Setting	Function
	Pin 1-2	+12V
	Short/Closed
	Pin 3-4	Normal
	Short/Closed
	Pin 5-6	+5V
	Short/Closed
JP3: COM2 RS232 +5V/+12V Power Setting

JP3	Setting	Function
	Pin 1-2	+12V
	Short/Closed
	Pin 3-4	Normal
	Short/Closed
	Pin 5-6	+5V
	Short/Closed

8 MB820 User’s Manual