GMS81C50 datasheet(13/99 Pages) HYNIX

13 / 99 page

GMS81C50 Series

HYUNDAI

5. PIN FUNCTION

VDD: Supply voltage.

VSS: Circuit ground.

TEST: Used for shipping inspection of the IC. For normal

operation, it should be connected to VDD.

RESET: Reset the MCU.

XIN: Input to the inverting oscillator amplifier and input to

the internal main clock operating circuit.

XOUT: Output from the inverting oscillator amplifier.

R00~R07: R0 is an 8-bit CMOS bidirectional I/O port. R0

pins 1 or 0 written to the Port Direction Register can be

used as outputs or inputs.

R10~R17: R1 is an 8-bit CMOS bidirectional I/O port. R1

pins 1 or 0 written to the Port Direction Register can be

used as outputs or inputs.

In addition, R1 serves the functions of the various follow-

ing special features.

R20~R22, R30~R37 : R2 & R3 is a 8-bit CMOS bidirec-

tional I/O port. Each pins 1 or 0 written to the their Port Di-

rection Register can be used as outputs or inputs.

R40 : R40 is 1-bit CMOS bidirectional I/O port. This pin 1

or 0 written to the its Port Direction Register can be used

as outputs or inputs.

Port pin

Alternate function

R11

R12

R14

R15

R16

R17

INT1 (External Interrupt input 1)

INT2 (External Interrupt input 2)

/EC (Event Counter input )

T2 (Timer / Counter input 2)

T1 (Timer / Counter input 1)

T0 (Timer / Counter input 0)

GMS81C50 Datasheet(PDF) 13 Page - Hynix Semiconductor