A.4 Digital Output
Besides setting by the set digital output commands, the digital
outputs can be set by two other conditions.
When the host watchdog is enabled and a host watchdog
timeout occurs, the "safe value" is loaded into the digital
output ports. The set digital output commands have no effect
on the digital output ports until the host watchdog timeout
status is cleared. The host watchdog timeout status is saved in
the EEPROM. The status is not changed even after power-on
reset. It can be cleared only by the reset host watchdog timeout
status command ~AA1. See Section A.2 for host watchdog
details.
When the module is powered on and the host watchdog
timeout status is cleared, the "power-on value" is loaded into
the digital output ports. If the host watchdog timeout status is
not cleared on power-on, then the safe value is loaded into the
digital output ports.
Both the safe value and power-on value are set by the ~AA5V
command. Refer to Section 2.32 for details.
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