Fujitsu MB89950/950A Pager User Manual


 
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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.