w78c31b Winbond Electronics Corp America, w78c31b Datasheet - Page 9

• Manufacturer Part Number: w78c31b
• Description: 8-bit Microcontroller
• Manufacturer: Winbond Electronics Corp America

Note: Ports are read during S5P2, and output data becomes available at the end of S6P2. The timing data are referenced to
TIMING WAVEFORMS
Program Fetch Cycle
Data Read Cycle
ALE, since it provides a convenient reference.
PORT 2
PORT 0
XTAL1
PSEN
ALE
RD
PORT 2
PORT 0
XTAL1
PSEN
ALE
S4
Code
S1
A0-A7
T
S5
AAH
A0-A7
S2
T
T
AAS
S6
DAR
A8-A15
T
T
PDA
S3
APL
T
PSW
Data
S1
A8-A15
S4
T
DDA
A0-A7
S2
T
S5
T
DRD
PDH,
T
- 9 -
ALW
T
S6
S3
PDZ
DATA
Code
S1
S4
T
A0-A7
DDH,
S2
S5
Publication Release Date: October 1997
T
DDZ
S3
Data
S6
S4
S1
A0-A7
S5
S2
S6
W78C31B
S3
Revision A3