Toshiba TLCS-900/H1 Series Manual page 27

Example 2: Setting the clock
Changing from low-frequency (fs) to high-frequency (fc).
SYSCR0 EQU
SYSCR1 EQU
SYSCR2 EQU
LD
SET
SET
WUP: BIT
JR
RES
RES
X: Don't care, −: No change
<XEN>
X1, X2 pins
<XTEN>
XT1, XT2 pins
Warm-up timer
Counts up by f
End of warm-up timer
<SYSCK>
System Clock f
SYS
10E0H
10E1H
10E2H
(SYSCR2), 0 X 1 0 − − X X B ;
7, (SYSCR0)
2, (SYSCR0)
2, (SYSCR0)
NZ, WUP
3, (SYSCR1)
6, (SYSCR0)
SYS
Enables Clears and starts
high-frequency warm-up timer
92CH21-25
Sets warm-up time to 2
; Enables high-frequency oscillation.
; Clears and starts warm-up timer.
;
Detects stopping of warm-up timer.
;
; Changes f
SYS
; Disables low-frequency oscillation.
Counts up by fc
fs fc
Changes f
SYS
from fs to fc
Disables
End of warm-up
low-frequency
timer
TMP92CH21
14
/fc.
from fs to fc.
2009-06-19