User's Manual

MSM80C154S/83C154S/85C154HVS
160
Figure 4-63 Soft power down mode setting and I/O floating time chart (external ROM mode)
S1 S2 S3 S4 S5 S6
M1 or M2 M1
XTAL1
1 0
ALE
1 0
PSEN PORT 0 PORT 1
1 0
PORT 2
1 0
PORT 3
1 0
W-PCON
1 0
*PCON-bit 1
1 0
SOFT POWER DOWN MODE
S6
PORT DATA PORT DATA
PD SET CYCLE
1 0 1 0
IOCON-bit 0
*ALF=“1”
S1
FLOATING FLOATING FLOATING FLOATING
PCLPCL PCL
PCH PCHPCH
PORT DATA
1 0