HMS87C5216 Datasheet, PDF (60/76 Pages) List of Unclassifed Manufacturers – CMOS SINGLE-CHIP 8-BIT MICROCONTROLLER FOR UR(Universal Remocon) & WIRELESS KEYBOARD

HMS87C5216
15. STANDBY FUNCTION
To save power consumption, there is STOP modes. In this modes,
the execution of program stops.
15.1 Sleep Mode
SLEEP mode can be entered by setting the bit of SLEEP mode
register (SLPM). In the mode, CPU clock stops but oscillator
keeps running. B.I.T and a part of peripheral hardware execute,
but prescalerís output which provide clock to peripherals can be
stopped by program. (Except, PS10 canít stopped.) In SLEEP
mode, more consuming power can be saved by not using other
peripheral hardware except for B.I.T. By setting ENPCK (periph-
eral clock control bit) of CKCTLR (clock control register) to
``0``, peripheral hardware halted, and SLEEP mode is entered. To
release SLEEP mode by BITR (basic interval timer interrupt),
bit10 of prescaler should be selected as B.I.T input clock before
entering SLEEP mode. ``NOP`` instruction should be follows set-
ting of SLEEP mode for rising precharge time of data bus line.
(ex) setting of SLEEP mode : set the bit of SLEEP
; mode register (SLPM)
NOP
: NOP instruction
7
SLPM
-
SLEEP MODE CONTROL Register
-
-
-
-
-
-
0
SLPM0
W <00F0 h>
SLPM0
0
1
condition
sleep mode release
sleep mode
7
CKCTLR
-
Colck Control Register
0
-
WDTON ENPCK BTCL
BTS2
BTS1
BTS0
W <00C8 h>
ENCPK
0
1
Peripheral Clock
stopped
provided
15.2 STOP MODE
STOP mode can be entered by STOP instruction during program.
In STOP mode, oscillator is stopped to make all clocks stop,
which leads to less power consumption. All registers and RAM
data are preserved. ``NOP`` instruction should be follows STOP
instruction for rising precharge time of Data Bus line.
(ex) STOP : STOP instruction execution
NOP : NOP instruction
SEP. 2004 Ver 1.01