gc80c520g CORERIVER Semiconductor, gc80c520g Datasheet - Page 22

• Manufacturer Part Number: gc80c520g
• Description: Eprom / Rom / Romless Based 8-bit Turbo Microcontrollers
• Manufacturer: CORERIVER Semiconductor

P3SEL (E7h) : P3 Pull-up Control Register
P3 (B0h) : PORT3 Register
P3SEL.7 P3SEL.6 P3SEL.5 P3SEL.4 P3SEL.3 P3SEL.2 P3SEL.1 P3SEL.0
R/W(0) R/W(0) R/W(0) R/W(0) R/W(0) R/W(0) R/W(0) R/W(0)
R/W(1) R/W(1) R/W(1) R/W(1) R/W(1) R/W(1) R/W(1) R/W(1)
6.5. I/O Ports : PORT3[7:0]
P3.7
Quasi bi-directional port (Intel 8052 Compatible).
Pull-up resistors are switched on/off by changing the value of the P3SEL SFR.
The alternative functions are available only when the corresponding SFR bit is “1”
Read-Modify-Write instructions do not read port pin but the port SFR.
PORT3 Description
P3SEL[7:0] :
P3.0 = RXD
ANL
P3.6
/
ORL
P3.5
Pull-up resistor Enable
0 = Pull-up resistor ON / 1 = Pull-up resistor Off
PORT3 Pull-up resistor is
/
/
XRL
P3.1 = TXD
P3.4
/
JBC
/
P3.3
CPL
/
P3.2 = INT0
/
INC
P3.2
ON
/
after reset.
DEC
P3.1
/
/
P3.3 = INT1
DJNZ
P3.0
/
MOV PX.Y, C
/
P3.4 = T0, PWM0
CPU BUS
Alternative Function Output
/
CLR PX.Y
P3.0
SFR
Digital Input
/
/
QB
P3.5 = T1
SETB PX.Y
Q
2 OSC
Pulse
/
P3.6 = WR
MiDAS1.0 Family
/
P3.7 = RD
Pull-
up
P3SEL.0
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