Fujitsu MB89950/950A Pager User Manual


 
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CHAPTER 3 CPU
Table 3.7-2 Standby control register (STBC) bits
Bit Function
Bit 7 STP:
Stop bit
Sets the CPU entering stop mode.
Writing "1" to this bit sets the CPU entering stop mode.
Writing "0" to this bit has no effect on operation.
Reading this bit always returns "0".
Bit 6 SLP:
Sleep bit
Sets the CPU entering sleep mode.
Writing "1" to this bit sets the CPU entering sleep mode.
Writing "0" to this bit has no effect on operation.
Reading this bit always returns "0".
Bit 5 SPL:
Pin state
specification
bit
Specifies the states of the external pins during stop mode.
Writing "0" to this bit specifies that external pins hold their states (levels)
when entering stop mode.
Writing "1" to this bit specifies that external pins go to high-impedance state
when entering stop mode (pin with a pull-up resistor (optional) go to "H"
level).
Initialized to "0" by a reset.
Bit 4 RST:
Software
reset bit
Specifies a software reset.
Writing "0" to this bit generates an internal reset source for four instruction
cycles.
Writing "1" to this bit has no effect on operation.
Reading this bit always returns "1".
Bit 3
Bit 2
Bit 1
Bit 0
Unused bits The read value is indeterminate.
Writing to these bits has no effect on operation.