Advantech PCA-6774 user manual COM2 RS232-422-485 Select J3, Watchdog timer configuration

2.7 COM2 RS232-422-485 Select (J3)

Table 2.4: COM2 RS232-422-485 Select

PIN	RS232*	RS422	RS484
1-2	Closed	Open	Open
3-4	Open	Closed	Open
5-6	Open	Open	Closed

2.8 Watchdog timer configuration

An on-board watchdog timer reduces the chance of disruptions which EMP (electro-magnetic pulse) interference can cause. This is an invalu- able protective device for standalone or unmanned applications. Setup involves one jumper and running the control software (refer to Appendix A).

2.8.1 Watchdog timer output option (J2)

When the watchdog timer activates (CPU processing has come to a halt), it can reset the system or generate an interrupt on IRQ11. This can be set via setting J2 as shown below:

Table 2.5: Watchdog timer output option (J2)

*System reset IRQ 11

* default setting

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