8-bit two-clock 80C51 microcontroller with 32 segment × 4 LCD driver
s Serial ﬂash In-System Programming (ISP) allows coding while the device is mounted
in the end application.
s In-Application Programming (IAP) of the ﬂash code memory. This allows changing the
code in a running application.
s Watchdog timer with separate on-chip oscillator, requiring no external components.
The watchdog prescaler is selectable from eight values.
s Low voltage detect (brownout) allows a graceful system shutdown when power fails.
May optionally be conﬁgured as an interrupt.
s Idle and two different power-down reduced power modes. Improved wake-up from
Power-down mode (a LOW interrupt input starts execution). Typical power-down
current is 9 µA typical (total power-down with voltage comparators disabled).
s Active-LOW reset. On-chip power-on reset allows operation without external reset
components. A reset counter and reset glitch suppression circuitry prevent spurious
and incomplete resets. A software reset function is also available.
s Conﬁgurable on-chip oscillator with frequency range options selected by user
programmed ﬂash conﬁguration bits. Oscillator options support frequencies from
20 kHz to the maximum operating frequency of 18 MHz.
s Oscillator fail detect. The watchdog timer has a separate fully on-chip oscillator
allowing it to perform an oscillator fail detect function.
s Programmable port output conﬁguration options: quasi-bidirectional, open drain,
s Port ‘input pattern match’ detect. Port 0 may generate an interrupt when the value of
the pins match or do not match a programmable pattern.
s LED drive capability (20 mA) on all port pins. A maximum limit is speciﬁed for the
s Controlled slew rate port outputs to reduce EMI. Outputs have approximately 10 ns
minimum ramp times.
s Only power and ground connections are required to operate the P89LPC9401 when
internal reset option is selected.
s Four interrupt priority levels.
s Eight keypad interrupt inputs, plus two additional external interrupt inputs.
s Schmitt trigger port inputs.
s Second data pointer.
Preliminary data sheet
Rev. 01 — 5 September 2005
© Koninklijke Philips Electronics N.V. 2005. All rights reserved.
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