AXIOMTEK SYM76996VGGA Manual page 18

JSEL1/JSEL2: RS-232/422/485 Switch Headers for JCOM1
The headers determine that JCOM1 belongs to RS-232 (Default), 422, or 485.
JSEL1
RS-232 RS-422 RS-485
1-3 3-5 3-5
2-4 4-6 4-6
7-9 9-11 9-11
8-10 10-12 10-12
JSEL2
1-2 RS-232
3-4 RS-422
5-6 RS-485
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