4513_03 Datasheet, PDF (68/210 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCOMPUTER

HARDWARE
FUNCTION BLOCK OPERATIONS
Reset
(Stabilizing time a )
A
POF instruction
is executed
f(XIN) oscillation
Return input
(Stabilizing time a )
B
f(XIN) stop
(RAM back-up
mode)
Stabilizing time a : Time required to stabilize the f(XIN) oscillation is automatically generated by hardware.
Fig. 38 State transition
POF instruction
Reset input or
voltage drop detection
circuit output
Power down flag P
SQ
R
q Set source ^{• • • • • • •} POF instruction is executed
q Clear source ^{• • • • • •}Reset input
Software start
P = “1” ^Yes
?
No
Cold start
Warm start
Fig. 39 Set source and clear source of the P flag
Fig. 40 Start condition identified example using the SNZP in-
struction
4513/4514 Group User’s Manual
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