EM78P468N/EM78P468L
8-Bit Microcontroller
20
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Product Specification (V1.5) 02.15.2007
(This specification is subject to change without further notice)
6.2.15 IOC81/WDTCR (WDT Control Register)
(Address: 08h, Bit 0 of R5 = “1”)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
−
−
−
−
WDTE WDTP2 WDTP1 WDTP0
Bits 7 ~ 4:
Not used
Bit 3 (WDTE):
Watchdog timer enable. This control bit is used to enable the Watchdog
timer,
WDTE = “0”:
Disable WDT function
WDTE = “1”:
enable WDT function
Bits 2 ~ 0 (WDTP2 ~ WDTP0)
: Watchdog Timer prescaler bits. The WDT clock source
is sub-oscillation frequency.
WDTP2
WDTP1
WDTP0
WDT Rate
0 0 0 1:1
0 0 1 1:2
0 1 0 1:4
0 1 1 1:8
1 0 0
1:16
1 0 1
1:32
1 1 0
1:64
1 1 1
1:128
6.2.16 IOC91/CNT12CR (Counters 1, 2 Control Register)
(Address: 09h, Bit 0 of R5 = “1”)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
CNT2S CNT2P2 CNT2P1 CNT2P0 CNT1S CNT1P2 CNT1P1 CNT1P0
Bit 7(CNT2S):
Counter 2 clock source select 0/1
→
Fs/ Fm*
(*Fs: sub-oscillator clock, Fm: main-oscillator clock)
Bits 6~4 (CNT2P2 ~ CNT2P 0):
Counter 2 prescaler select bits
CNT2P2
CNT2P1
CNT1P0
Counter 2 Scale
0 0 0
1:2
0 0 1
1:4
0 1 0
1:8
0 1 1
1:16
1 0 0
1:32
1 0 1
1:64
1 1 0
1:128
1 1 1
1:256