EMC EM78612 - Manual (Page 14)

EM78612
Universal Serial Bus Microcontroller
12 • ••• Product Specification(V1.0) 03.22.2006
(This specification is subject to change without further notice)
R3 [2] Zero flag. It will be set to 1 when the result of an arithmetic or logic operation is
zero.
R3 [3] Power down flag. It will be set to 1 during Power-on phase or by “WDTC”
command and cleared when the MCU enters into Power down mode. It remains
in previous state after WatchDog Reset.
1: Power-on.
0: Power down
R3 [4] Time-out flag. It will be set to 1 during Power-on phase or by “WDTC” command.
It is reset to 0 by WDT time-out.
1: WatchDog timer without overflow.
0: WatchDog timer with overflow.
The various states of Power down flag and Time-out flag at different conditions are
shown below:
Condition
1
1
0
1
1 1
1
*P
0
0
Power-on reset
WDTC instruction
WDT time-out
Power down mode
Wakeup caused by port change during Power down mode
*P: Previous status before WDT reset
R3 [5] Page selection bit. This bit is used to select a page of program memory (refer to
R2, Program Counter).
PS0 Program Memory Page [Address]
0 Page 0 [0000-03FF]
1 Page 1 [0400-07FF]
R3 [6,7] Reserved registers.