EM78451
8-Bit Microcontroller
Symbol
Pin No.
Type
Function Description
By connecting P75 and P77 together, P75 can be pulled-high by software
and it is also a pin-change wake-up pin.
P77 can be defined as an open-drain output.
General bi-directional port. All of its pins can be pulled-high by software,
and pin-change wake-up pins.
General bi-directional I/O port. All of its pins can be pulled-high * * by
software.
Power supply pin.
Ground pin.
An interrupt schmitt-triggered pin. The function of interrupt triggers at the
falling edge. Users can enable it by software. The internal pull-up resistor
is around 50K ohm.
Serial data in for SPI
Serial data out for SPI.
Serial clock for SPI.
/Slave select for SPI.
DATA
3
I/O
P60~P67
P50~P57
VDD
VSS
/INT
SDI
SDO
SCK
/SS
27~34
11~18
38
1
2
7
8
9
10
I/O
I/O
-
-
I
I/O
I/O
I/O
I/O
4
FUNCTION DESCRIPTION
W DT Tim er
W DT
Tim e-out
PC
STACK 1
STACK 2
STACK 3
Prescaler
O scillator/
Tim m ing
Control
/ INT
ROM
STACK 4
STACK 5
R1(TCC)
Interrupt
Control
Instruction
Register
ALU
RAM
Instruction
Decoder
R3
R4
ACC
TM R1
Sleep
&
W ake Up
Control
DAT A & CONT ROL BUS
IOC5
R5
IOC6
R6
IOC7
R7
IOC8
R8
IOC9
R9
SPI
ENG IN
PPPPPPPP
55555555
01234567
PPPPPPPP
66666666
01234567
P
7
0
P
7
1
P
7
2
PPPPPPPP
88888888
01234567
P PP P P
9 9 9 9 9
0 1 2 3 4
/ / /
S S S
DD C
I O K
P
5
5
/
/
S
S
Fig. 2 Functional Block Diagram
Product Specification (V1.2) 05.27.2004
(This specification is subject to change without further notice)
•
3
EMC [ ELAN MICROELECTRONICS CORP ]
