UPD784224 Datasheet, PDF (52/92 Pages) NEC – 16/8-BIT SINGLE-CHIP MICROCONTROLLERS

µPD784224, 784225, 784224Y, 784225Y
10. STANDBY FUNCTION
This function is to reduce the power consumption of the chip, and can be used in the following modes:
• HALT mode
: Stops supply of the operating clock to the CPU. This mode is used in combination
with the normal operation mode for intermittent operation to reduce the average
power consumption.
• IDLE mode
: Stops the entire system with the oscillator continuing operation. The power
consumption in this mode is close to that in the STOP mode. However, the time
required to restore the normal program operation from this mode is almost the
same as that from the HALT mode.
• STOP mode
: Stops the main system clock and thereby to stop all the internal operations of the
chip. Consequently, the power consumption is minimized with only leakage
current flowing.
• Power-saving mode
: The main system clock is stopped with the subsystem clock used as the system
clock. The CPU can operate on the subsystem clock to reduce the current
consumption.
• Power-saving HALT mode : This is a standby function in the power-saving mode and stops the operation clock
of the CPU, to reduce the power consumption of the entire system.
• Power-saving IDLE mode : This is a standby function in the power-saving mode and stops the entire system
except the oscillator, to reduce the power consumption of the entire system.
These modes are programmable.
The macro service can be started from the HALT mode and power-saving HALT mode.
After executing macro service processing, it returns to the HALT mode.
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Data Sheet U12376EJ1V0DS00