1 operating states in standby mode, Operating states in standby mode – FUJITSU Semiconductor Controller MB89950/950A User Manual

Page 72

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CHAPTER 3 CPU

3.7.1

Operating States in Standby Mode

This section describes the operating states of the CPU and peripheral functions in
standby mode.

■ Operating states during standby mode

●

Pin States in Standby Mode

Almost all I/O pins will either keep the state they were placed in, or go to the high-impedance state

according to the pin state control bit of the standby control register (STBC: SPL) just prior to going to the

stop mode. This is true regardless of the clock mode.

See Appendix E "MB89950/950A Series Pin States" for pin states in standby mode.

Table 3.7-1 Operating states of the CPU and peripheral functions in standby mode

Function

Main clock mode

Run

Sleep

Stop

(SPL = "0")

Stop

(SPL = "1")

Main clock

Operating

Operating

Stop

Stop

CPU

Instructions

Operating

Stop

Stop

Stop

ROM

Operating

Hold

Hold

Hold

RAM

Peripheral
functions

I/O ports

Operating

Hold

Hold

Hi-Z

(*1)

Timebase timer

Operating

Operating

Stop

Stop

8-bit PWM timer

Operating

Operating

Stop

Stop

8-bit PWC timer

Operating

Operating

Stop

Stop

Watchdog timer

Operating

Stop

Stop

Stop

LCD controller/driver

Operating

Operating

Stop

Stop

External Interrupts

Operating

Operating

Operating

Operating

Serial I/O

Operating

Operating

Stop

Stop

UART

Operating

Operating

Stop

Stop

*1: If pull-up is selected, it will be "H" level.

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