AAEON AEC-6612 Rev.A - Manual (Page 42)

E m b e d d e d C o n t r o l l e r A E C - 6 6 1 2
Appendix A Programming the Watchdog Timer A-3
(3) Exit the W83627DHG config Mode. Undesired result may
occur if the config Mode is not exited normally.
(1) Enter the W83627DHG config Mode
To enter the W83627DHG config Mode, two special I/O write
operations are to be performed during Wait for Key state. To
ensure the initial state of the key-check logic, it is necessary to
perform two write operations to the Special Address port (2EH).
The different enter keys are provided to select configuration ports
(2Eh/2Fh) of the next step.
Address Port Data Port
87h,87h: 2Eh 2Fh
(2) Modify the Data of the Registers
All configuration registers can be accessed after entering the config
Mode. Before accessing a selected register, the content of Index
07h must be changed to the LDN to which the register belongs,
except some Global registers.
(3) Exit the W83627DHG config Mode
The exit key is provided to select configuration ports (2Eh/2Fh) of
the next step.
Address Port Data Port
0aah: 2Eh 2Fh
WatchDog Timer Register I (Index=F5h, Default=00h)
CRF5 (PLED and KBC P20 Control Mode Register)
Bit 7-5 : select PLED mode
= 000 Power LED pin is driven high.
= 001 Power LED pin outputs 0.5Hz pulse
with 50% duty cycle.