Canvys AOpen DE965, Assembly Manual

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CODE FLOW-CHART
Start
Initial Watchdog Pin
Stop Timer and
Clear Status
1. Initial Watchdog Pin
(1)set -> Logical Device: Global
CR: 0x2D
Bit: 0 = 0 WDTO.
(2)set -> Logical Device: 0x09
CR: 0X30
Bit:3 = 1 activate GPIO5
CR: 0xE0, 0xE1, 0xE2
Bit: 6, Bit: 7, Bit: 6
= 0 GPIO port is programmed as an output port.
1. Stop timer
(1)set -> Logical Device: 0x08
CR: 0xF6
Bit: 7~0 = 0x00 Stop timer
(2)Set -> Logical Device 0x08
CR 0x30
Bit:0 = 1, activate WDTO
2. Clear Status
(1)set -> Logical Device: 0x08
CR: 0xF7
Bit: 4 = 0 Timer counting