mpc82l54 Megawin Technology, mpc82l54 Datasheet - Page 57

• Manufacturer Part Number: mpc82l54
• Description: 8-bit Micro-controller
• Manufacturer: Megawin Technology

Power Management
MEGAWIN
IDLE Mode
An instruction setting PCON.0 causes the device go into the idle mode, the internal clock is
gated off to the CPU but not to the interrupt, timer, PCA, SPI, ADC, WDT and serial port
functions.
There are two ways to terminate the idle. Activation of any enabled interrupt will cause
PCON.0 to be cleared by hardware in order to terminating the idle mode. The interrupt will be
serviced, and following RETI instruction: the next instruction to be executed will be performed
right after the instruction that puts the device into idle. Another way to wake-up from idle is to
pull pin RST high to generate internal hardware reset.
Divider for system clock
A clock divider(CLKDIV) in the frond end of the device is designed to slow down the operation
speed of MPC82x54A, and by doing that is to save the operating power dynamically. Different
from the same register in MPC82x54A MCU, the content in PCON2 is always effective without
the need to operate in IDLE mode.
SFR: PCON2 (Power Control 2)
{CKS2, CKS1, CKS0}: Clock selector under idle mode
Bit-7
-
{0, 0,0} : = (default)
{0, 0, 1} : =
{0, 1, 0} : =
{0, 1, 1} : =
{1, 0, 0} : =
{1, 0, 1} : =
{1, 1, 0} : =
{1, 1, 1} : =
In idle mode, clock is not divided (default state)
In idle mode, clock is divided by 2
In idle mode, clock is divided by 4
In idle mode, clock is divided by 8
In idle mode, clock is divided by 16
In idle mode, clock is divided by 32
In idle mode, clock is divided by 64
In idle mode, clock is divided by 128
Bit-6
-
Bit-5
-
MPC82x54A Data Sheet
Bit-4
-
Bit-3
-
CKS2
Bit-2
CKS1
Bit-1
CKS0
Bit-0
57