IEI Technology WAFER-6820, Руководство пользователя

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2.10 COM2 RS-232, RS-422 or RS-485 Setting (J7)
The COM2 (CN15) can be set to RS-232 or RS-422/485 for industrial
field site application. Moreover when this port was set to the RS-485
mode, the board equipped with auto-direction IC will automatically
sense the data direction to eliminate the data collision. This is
especially important in WINDOWS programming which do not allow
the program to catch the control pin at your wish.
J7 DESCRIPTION
1-2 RS232
3-4 RS422/RS485
2.11 Watchdog Timer Setting (J8)
R reading port 443H enables the Watch-Dog Timer. It should be re-
triggered before the time-out period ends, otherwise it will assume the
program operation is abnormal and will issue a reset signal to start
again, or activate NMI to CPU. Reading port 043/843H disables the
watchdog Timer. Refer to Appendix A for more detailed information on
Watchdog Timer
J8 DESCRIPTION
1-2
ACTIVATE NMI TO CPU WHEN WDT TIME-OUT
2-3
RESET WHEN WDT TIME-OUT
OPEN
DISABLE WDT
2.12 Reset Button (J9)
You can press Reset Button (J9) to reset your computer easily.
PIN NO. DISCRPTION
1 Reset _In
2 GND