W77IE58 Datasheet, PDF (5/90 Pages) Winbond – 8-BIT MICROCONTROLLER

Preliminary W77IE58
Pin Description, continued
SYMBOL TYPE
DESCRIPTIONS
P3.0−P3.7 I/O PORT 3: Port 3 is a bi-directional I/O port with internal pull-ups. All bits have
alternate functions, which are described below:
RXD (P3.0) : Serial Port 0 input
TXD (P3.1) : Serial Port 0 output
INT0 (P3.2) : External Interrupt 0
INT1 (P3.3) : External Interrupt 1
T0 (P3.4) : Timer 0 External Input
T1 (P3.5) : Timer 1 External Input
WR (P3.6) : External Data Memory Write Strobe
P4.0−P4.3
RD (P3.7) : External Data Memory Read Strobe
I/O PORT 4: Port 4 is a 4-bit bi-directional I/O port. The P4.0 also provides the
alternate function WAIT which is the wait state control signal.
* Note: TYPE I: input, O: output, I/O: bi-directional.
Publication Release Date: July 2000
-5-
Revision A1