Pad Description

Pad Name

I/O

Options

Description

PA0~PA7

I/O

Wake-up

Pull-high*

CMOS or Schmitt

Input

Bidirectional 8-bit input/output ports

Each bit can be configured as a wake-up input by options. Software instruc-

tions determine the CMOS output or Schmitt trigger or CMOS input with or with-

out pull high resistor (by options).

PB0~PB7

I/O

Pull-high*

Bidirectional 8-bit input/output ports

Software instructions determine the CMOS output or Schmitt trigger input

(pull-high depends on options).

VSS

¾¾

Negative power supply, ground

INT

I

¾

External interrupt Schmitt trigger without pull high resistor

Edge trigger is activated during high to low transition.

TMR0

I

¾

Schmitt trigger input for Timer/Event Counter 0

TMR1

I

¾

Schmitt trigger input for Timer/Event Counter 1

PC0~PC7

I/O

Pull-high*

Bidirectional 8-bit input/output ports

Software instructions determine the CMOS output or Schmitt trigger input

(pull-high depends on options).

RES

I

¾

Schmitt trigger reset input, active low

VDD

¾¾

Positive power supply

OSC1

OSC2

I

O

Crystal

or RC

or RTC

OSC1 and OSC2 are connected to an RC network or a crystal (by options) for

the internal system clock. In the case of RC operation, OSC2 is the output

terminal for 1/4 system clock.

These two pins also can be optioned as an RTC oscillator (32768Hz). In this

case, the system clock comes from an internal RC oscillator whose fre-

quency has 4 options (3.2MHz, 1.6MHz, 800kHz, 400kHz)

PD0~PD7

I/O

Pull-high*

Bidirectional 8-bit input/output ports

Software instructions determine the CMOS output or Schmitt trigger input

(pull-high depends on options).

PE0~PE7

I/O

Pull-high*

Bidirectional 8-bit input/output ports

Software instructions determine the CMOS output or Schmitt trigger input

(pull-high depends on options).

PF0~PF7

I/O

Pull-high*

Bidirectional 8-bit input/output ports

Software instructions determine the CMOS output or Schmitt trigger input

(pull-high depends on options).

PG0~PG7

I/O

Pull-high*

Bidirectional 8-bit input/output ports

Software instructions determine the CMOS output or Schmitt trigger input

(pull-high depends on options).

Note:

* The pull-high resistors of each I/O port (PA, PB, PC, PD, PE, PF, PG) are controlled by an option.

CMOS or Schmitt trigger option of port A is controlled by an option.

Absolute Maximum Ratings

Storage Temperature ............................

-50°Cto125°C

Operating Temperature...........................

-40°Cto85°C

Note: These are stress ratings only. Stresses exceeding the range specified under

²Absolute Maximum Ratings² may

cause substantial damage to the device. Functional operation of this device at other conditions beyond those

listed in the specification is not implied and prolonged exposure to extreme conditions may affect device reliabil-

ity.

HT48R70A-1/HT48C70-1

Rev. 1.60

5

June 9, 2004