IBM MiEM78P468L Product Specification page 30

EM78P468N/EM78P468L
8-Bit Microcontroller
WDT Setting Flowchart
TCC Setting Flowchart
from External Input
*set clock source from external TCC pin
(set bit 4 of IOC71 to "1")
*set P5.6/TCC for TCC input Pin
( set bit 2 of RE to "1" and set bit 6 of IOC 50 to "1")
*choose TCC pin operation edge
(set by bit 4 of IOC71)
*choose TCC prescaler
(set by bit 0 to bit 3 of IOC71)
* Enable TCC interrupt Mask
(set bit 0 of IOCF0 to "1")
*Clear TCC interrupt Flag
(set bit 0 of RF to "0")
Enable TCC to start count
(use ENI instruction)
24 •
START
N
Use WDT function ?
Y
Enable WDT function : set bit 7 of
Code option Word 0 to "0"
Setting WDT prescaler
(IOC81 register)
Enable WDT
(bit 3 of IOC81)
END
START
TCC clock source?
External/ instruction cycle
END
Disable WDT function : set bit 7 of
Code option Word 0 to "1"
WDTtime= prescaler*256/Fs
Fs: sub-oscillator frequency
from Instruction Cycle
*choose TCC clock source from instruction cycle
(set bit 4 of IOC71 to "0")
*choose TCC prescaler
(set by bit 0 to bit 3 of IOC71)
Product Specification (V1.5) 02.15.2007
(This specification is subject to change without further notice)