87C51F Intel Corporation, 87C51F Datasheet - Page 4

• Manufacturer Part Number: 87C51F
• Description: CHMOS SINGLE-CHIP 8-BIT MICROCONTROLLER
• Manufacturer: Intel Corporation

AUTOMOTIVE 87C51FA FB FC FC-20
Port 0 is also the multiplexed low-order address and
data bus during accesses to external Program and
Data Memory In this application it uses strong inter-
nal pullups when emitting 1’s and can source and
sink several LS TTL inputs
Port 0 also receives the code bytes during EPROM
programming and outputs the code bytes during
program verification External pullup resistors are re-
quired during program verification
Port 1 Port 1 is an 8-bit bidirectional I O port with
internal pullups The Port 1 output buffers can drive
LS TTL inputs Port 1 pins that have 1’s written to
them are pulled high by the internal pullups and in
that state can be used as inputs As inputs Port 1
pins that are externally pulled low will source current
(I
ups
In addition Port 1 serves the functions of the follow-
ing special features of the 87C51FB FC
Port 1 receives the low-order address bytes during
EPROM programming and verifying
Port 2 Port 2 is an 8-bit bidirectional I O port with
internal pullups The Port 2 output buffers can drive
LS TTL inputs Port 2 pins that have 1’s written to
them are pulled high by the internal pullups and in
that state can be used as inputs As inputs Port 2
pins that are externally pulled low will source current
(I
ups
4
IL
IL
Port Pin
P1 0
P1 1
P1 2
P1 3
P1 4
P1 5
P1 6
P1 7
on the data sheet) because of the internal pull-
on the data sheet) because of the internal pull-
T2 (External Count Input to
Timer Counter 2)
T2EX (Timer Counter 2 Capture
Reload Trigger and Direction Control)
ECI (External Count Input to the PCA)
CEX0 (External I O for Compare
Capture Module 0)
CEX1 (External I O for Compare
Capture Module 1)
CEX2 (External I O for Compare
Capture Module 2)
CEX3 (External I O for Compare
Capture Module 3)
CEX4 (External I O for Compare
Capture Module 4)
Alternate Function
PACKAGES
87C51FA FB FC
Diagrams are for pin reference only Package sizes are
not to scale
Do not connect reserved pins
EPROM only
Figure 3 Pin Connections (Top View)
Part
PAD (PLCC)
Prefix
DIP
N
P
40-Pin Plastic DIP
44-Pin PLCC
Package Type
270961 – 3
270961 – 4