HT48CXX/HT48RXX
Pin Description of HT48C50
Pin Name
I/O
Mask
Option
Wake-up
Pull-high
or None
Function
Bidirectional 8-bit input/output ports
Each bit can be configured as a wake-up input by mask option.
Software instructions determine the CMOS output or schmitt
trigger input with or without a pull high resistor (by mask option).
Bidirectional 8-bit input/output ports
Software instructions determine the CMOS output or schmitt
trigger input with or without a pull high resistor (by mask
option).
Negative power supply, GND
External interrupt schmitt trigger input with a pull high
resistor. Edge triggered is activated on a high to low transition.
Schmitt trigger input for timer/event counter 0
Schmitt trigger input for timer/event counter 1
Bidirectional 8-bit input/output ports
Software instructions determine the CMOS output or schmitt
trigger input with or without a pull high resistor (by mask
option).
Schmitt trigger reset input, active low
Positive power supply
OSC1 and OSC2 are connected to an RC network or a crystal
(by mask option) for the internal system clock. In the case of RC
operation, OSC2 is the output terminal for 1/4 system clock.
Bidirectional 8-bit Input/Output port. Software instructions
determine the CMOS output or schmitt trigger input with or
without a pull high resistor (by mask option).
PA0~PA7
I/O
PB0~PB7
I/O
Pull-high
or None
—
—
—
—
Pull-high
or None
—
—
Crystal or
RC
Pull-high
or None
VSS
INT
TMR0
TMR1
—
I
I
I
PC0~PC7
I/O
RES
VDD
OSC1
OSC2
I
—
I
O
PD0~PD7
I/O
8
25th May ’99
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
