
HMS87C1304A/HMS87C1302A
HYUNDAI MicroElectronics
6
Preliminary
Jan. 2001
5. PIN FUNCTION
V
DD
: Supply voltage.
V
SS
: Circuit ground.
RESET
: Reset the MCU.
X
IN
: Input to the inverting oscillator amplifier and input to
the internal main clock operating circuit.
X
OUT
: Output from the inverting oscillator amplifier.
RA0~RA7
: RA is an 8-bit, CMOS, bidirectional I/O port.
RA pins can be used as outputs or inputs according to “1”
or “0” written the their Port Direction Register(RAIO).
In addition, RA serves the functions of the various special
features in Table 5-1 .
RB0~RB7
: RB is a 8-bit, CMOS, bidirectional I/O port.
RB pins can be used as outputs or inputs according to “1”
or “0” written the their Port Direction Register(RBIO).
RB serves the functions of the various following special
features
in
Table 5-2
RC0, RC1
: RC is a 2-bit, CMOS, bidirectional I/O port.
RC pins can be used as outputs or inputs according to “1”
or “0” written the their Port Direction Register(RCIO).
RD0~RD3
: RD is a 4-bit, CMOS, bidirectional I/O port.
RC pins can be used as outputs or inputs according to “1”
or “0” written the their Port Direction Register(RDIO).
Port pin
Alternate function
Preimnary
RA0
RA1
RA2
RA3
RA4
RA5
RA6
RA7
EC0 ( Event Counter Input Source )
AN1 ( Analog Input Port 1 )
AN2 ( Analog Input Port 2 )
AN3 ( Analog Input Port 3 )
AN4 ( Analog Input Port 4 )
AN5 ( Analog Input Port 5 )
AN6 ( Analog Input Port 6 )
AN7 ( Analog Input Port 7 )
Table 5-1 RA Port
Port pin
Alternate function
RB0
RB1
RB2
RB3
RB4
AN0 ( Analog Input Port 0 )
AVref ( External Analog Reference Pin )
BUZ ( Buzzer Driving Output Port )
INT0 ( External Interrupt Input Port 0 )
INT1 ( External Interrupt Input Port 1 )
PWM0 (PWM0 Output)
COMP0 (Timer1 Compare Output)
Table 5-2 RB Port