Fujitsu MB89950/950A Pager User Manual


 
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CHAPTER 4 I/O PORTS
Operation in stop mode
The pins go to the high-impedance state, if the pin state specification bit in the standby control register
(STBC: SPL) is "1" when the device goes to stop mode. This is achieved by forcibly setting the output
transistor "OFF" regardless of the DDR4 register value.
Table 4.6-4 "Port 4 pin state" lists the port 4 pin states.
Reference:
Pins with a pull-up resistor go to the "H" level (pull-up state) rather than to the high-impedance state
when the output transistor is turned "OFF".
Table 4.6-4 Port 4 pin state
Pin name
Normal operation
sleep mode
stop mode (SPL = "0")
Stop mode (SPL = "1") Reset
P40 to P46/INT0 General-purpose I/O port/peripheral I/O Hi-Z Hi-Z
SPL: Pin state specification bit in the standby control register (STBC)
Hi-Z: High impedance