W742S81A Datasheet, PDF (28/47 Pages) Winbond – 4 BIT MICROCONTROLLER

W742S81A
Bit 3 = 0 RB.3 works as output pin; Bit 3 = 1 RB.3 works as input pin
At initial reset, the port RB is input mode (PM2 = 1111B).
6.17.4 Port Mode 5 Register (PM5)
The port mode 5 register is organized as 4-bit binary register (PM5.0 to PM5.3). PM5 can be used to
control the input/output mode of port RD. PM5 is controlled by the MOV PM5, #I instruction. The bit
descriptions are as follows:
3210
PM5 w w w w
Note: W means write only.
Bit 0 = 0 RD.0 works as output pin; Bit 0 = 1 RD.0 works as input pin
Bit 1 = 0 RD.1 works as output pin; Bit 1 = 1 RD.1 works as input pin
Bit 2 = 0 RD.2 works as output pin; Bit 2 = 1 RD.2 works as input pin
Bit 3 = 0 RD.3 works as output pin; Bit 3 = 1 RD.3 works as input pin
At initial reset, the port RD is input mode (PM5 = 1111B).
6.18 Input Ports RC
Port RC consists of pins RC.0 to RC.3. Each pin of port RC can be connected to a pull-up resistor, which is
controlled by the port mode 0 register (PM0). When the PEF, HEF, and IEF corresponding to the RC port
are set, a signal change at the specified pins of port RC will execute the hold mode release or interrupt
subroutine. Port status register 0 (PSR0) records the status of ports RC, i.e., any signal changes on the pins
that make up the ports. PSR0 can be read out and cleared by the MOV R, PSR0, and CLR PSR0
instructions. In addition, the falling edge signal on the pin of port RC specified by the instruction MOV
SEF, #I will cause the device to exit the stop mode. Refer to Figure 6-12 and the instruction table for
more details.
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