P89LPC901 PHILIPS [NXP Semiconductors], P89LPC901 Datasheet - Page 9

• Manufacturer Part Number: P89LPC901
• Description: 8-bit microcontrollers with two-clock 80C51 core 1 kB 3 V Flash with 128-byte RAM
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
Table 3:
9397 750 12293
Product data
Symbol
P3.0 - P3.1
V
V
SS
DD
P89LPC901 pin description
Pin
2, 3
3
2
8
1
Type
I/O
I/O
O
O
I/O
I
I
I
Description
Port 3: Port 3 is an I/O port with a user-configurable output types. During reset Port 3
latches are configured in the input only mode with the internal pull-up disabled. The
operation of port 3 pins as inputs and outputs depends upon the port configuration
selected. Each port pin is configured independently. Refer to
configurations”
All pins have Schmitt triggered inputs.
Port 3 also provides various special functions as described below:
P3.0 — Port 3 bit 0.
XTAL2 — Output from the oscillator amplifier (when a crystal oscillator option is
selected via the FLASH configuration).
CLKOUT — CPU clock divided by 2 when enabled via SFR bit (ENCLK - TRIM.6). It
can be used if the CPU clock is the internal RC oscillator, Watchdog oscillator or
external clock input, except when XTAL1/XTAL2 are used to generate clock source
for the real time clock/system timer.
P3.1 — Port 3 bit 1.
XTAL1 — Input to the oscillator circuit and internal clock generator circuits (when
selected via the FLASH configuration). It can be a port pin if internal RC oscillator or
Watchdog oscillator is used as the CPU clock source, and if XTAL1/XTAL2 are not
used to generate the clock for the real time clock/system timer.
Ground: 0 V reference.
Power Supply: This is the power supply voltage for normal operation as well as Idle
and Power-down modes.
…continued
Rev. 04 — 21 November 2003
and
Table 13 “DC electrical characteristics”
8-bit microcontrollers with two-clock 80C51 core
P89LPC901/902/903
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
for details.
Section 8.12.1 “Port
9 of 55