EM78156E
8-Bit Microcontroller with MASK ROM
Table 2 EM78156EAS Pin Description
Symbol Pin No.
Type
Function
VDD
15
17
-
■ Power supply.
■ XTAL type: Crystal input terminal or external clock input pin.
■ ERC type: RC oscillator input pin.
OSCI
I
■ XTAL type: Output terminal for crystal oscillator or external clock input pin.
■ RC type: Instruction clock output.
OSCO
16
I/O
■ External clock signal input.
■ The real time clock/counter (with Schmitt trigger input pin), must be tied to
VDD or VSS if not in use.
■ Input pin with Schmitt trigger. If this pin remains at logic low, the controller
will also remain keep in reset condition.
TCC
4
5
I
I
/RESET
■ P50~P53 are bi-directional I/O pins.
18, 19,
2, 3
P50~P53
I/O
I/O
■ P50 and P51 can also be defined as the R-option pins.
■ P50~P52 can also be pulled-down by software.
■ P60~P67 are bi-directional I/O pins.
■ These can be pulled-high or can be open-drain by software programming.
■ P60~P63 can be pulled-down also by software.
P60~P67 7~14
/INT
VSS
7
6
I
■ External interrupt pin triggered by falling edge.
■ Ground.
-
Table 3 EM78156EKM Pin Description
Symbol Pin No.
Type
Function
VDD
15,16
18
-
■ Power supply.
■ XTAL type: Crystal input terminal or external clock input pin.
■ ERC type: RC oscillator input pin.
OSCI
I
■ XTAL type: Output terminal for crystal oscillator or external clock input pin.
■ RC type: Instruction clock output.
OSCO
17
I/O
■ External clock signal input.
■ The real time clock/counter (with Schmitt trigger input pin), must be tied to
VDD or VSS if not in use.
■ Input pin with Schmitt trigger. If this pin remains at logic low, the controller
will also remain in reset condition.
TCC
3
4
I
I
/RESET
■ P50~P53 are bi-directional I/O pins.
■ P50 and P51 can also be defined as the R-option pins.
■ P50~P52 can be pulled-down by software.
■ P60~P67 are bi-directional I/O pins.
■ These can be pulled-high or can be open-drain by software programming.
■ P60~P63 can also be pulled-down by software.
19, 20,
1, 2
P50~P53
I/O
I/O
P60~P67 7~14
/INT
VSS
7
I
■ External interrupt pin triggered by falling edge.
■ Ground.
5, 6
-
Product Specification (V1.3) 07.29.2004
• 3
(This specification is subject to change without further notice)
ELAN [ ELAN MICROELECTRONICS CORP ]
