W742C813 Datasheet, PDF (30/56 Pages) Winbond – 4 BIT MICROCONTROLLER

W742E/C813
Input/Output Pin of the P0
DATA
BUS
Output
Buffer
Enable
PM6.n
MOV P0,R instruction
I/O PIN
P0.n
Enable
MOVA R,P0 instruction
Figure 5-11 Architecture of P0 Input/Output pins
5.17.1 Port Mode 0 Register (PM0)
The port mode 0 register is organized as 4-bit binary register (PM0.0 to PM0.3). PM0 can be used to
determine the port structure; it is controlled by the MOV PM0, #I instruction. The bit description is as
follows:
3210
PM0 w w w w
Note: W means write only.
Bit 0 = 0 RA port is CMOS output type. Bit 0 = 1 RA port is NMOS open drain output type.
Bit 1 = 0 RB port is CMOS output type. Bit 1 = 1 RB port is NMOS open drain output type.
Bit 2 = 0 RC port pull-high resistor is disabled. Bit 2 = 1 RC port pull-high resistor is enabled.
Bit 3 = 0 RD port pull-high resistor is disabled. Bit 3 = 1 RD port pull-high resistor is enabled.
5.17.2 Port Mode 1 Register (PM1)
The port mode 1 register is organized as 4-bit binary register (PM1.0 to PM1.3). PM1 can be used to
control the input/output mode of port RA. PM1 is controlled by the MOV PM1, #I instruction. The bit
description is as follows:
3210
PM1 w w w w
Note: W means write only.
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