Toshiba TLCS-900/L1 Series Manual page 21

Example 1: Setting the clock
Changing from high frequency (fc) to low frequency (fs).
SYSCR0 EQU
SYSCR1 EQU
SYSCR2 EQU
WDMOD EQU
LD
SET
SET
WUP: BIT
JR
SET
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
Enables
low frequency
00E0H
00E1H
00E2H
005CH
(SYSCR2), X−11− − − −B ; Sets warm-up time to 2
6, (SYSCR0) ; Enables low-frequency oscillation.
2, (SYSCR0) ; Clears and starts warm-up timer.
2, (SYSCR0) ;
Detects stopping of warm-up timer.
NZ, WUP ;
3, (SYSCR1) ; Changes f
7, (SYSCR0) ; Disables high-frequency oscillation.
Counts up by fs
SYS
fc
Clears and starts
warm-up timer
End of warm-up timer
91C824-19
TMP91C824
16
/fs.
from fc to fs.
SYS
fs
Chages f Disabiles
SYS
from fc to fs high frequency
2008-02-20