P89LPC932A1 View Datasheet(PDF) - Philips Electronics

Part Name

Description

Manufacturer

P89LPC932A1

8-bit microcontroller with accelerated two-clock 80C51 core 8 kB 3 V byte-erasable flash with 512-byte data EEPROM

Philips Electronics 

Philips Semiconductors

P89LPC932A1

8-bit microcontroller with accelerated two-clock 80C51 core

After power-up this input will function either as an external reset input or as a digital input

as defined by the RPE bit. Only a power-up reset will temporarily override the selection

defined by RPE bit. Other sources of reset will not override the RPE bit.

Reset can be triggered from the following sources:

• External reset pin (during power-up or if user configured via UCFG1).

• Power-on detect.

• Brownout detect.

• Watchdog timer.

• Software reset.

• UART break character detect reset.

For every reset source, there is a flag in the Reset Register, RSTSRC. The user can read

this register to determine the most recent reset source. These flag bits can be cleared in

software by writing a logic 0 to the corresponding bit. More than one flag bit may be set:

• During a power-on reset, both POF and BOF are set but the other flag bits are

cleared.

• For any other reset, previously set flag bits that have not been cleared will remain set.

7.16.1 Reset vector

Following reset, the P89LPC932A1 will fetch instructions from either address 0000H or

the Boot address. The Boot address is formed by using the Boot Vector as the high byte of

the address and the low byte of the address = 00H.

The Boot address will be used if a UART break reset occurs, or the non-volatile Boot

Status bit (BOOTSTAT.0) = 1, or the device is forced into ISP mode during power-on (see

P89LPC932A1 User manual). Otherwise, instructions will be fetched from address 0000H.

7.17 Timers/counters 0 and 1

The P89LPC932A1 has two general purpose counter/timers which are upward compatible

with the standard 80C51 Timer 0 and Timer 1. Both can be configured to operate either as

timers or event counter. An option to automatically toggle the T0 and/or T1 pins upon timer

overflow has been added.

In the ‘Timer’ function, the register is incremented every machine cycle.

In the ‘Counter’ function, the register is incremented in response to a 1-to-0 transition at its

corresponding external input pin, T0 or T1. In this function, the external input is sampled

once during every machine cycle.

Timer 0 and Timer 1 have five operating modes (modes 0, 1, 2, 3 and 6). Modes 0, 1, 2

and 6 are the same for both Timers/Counters. Mode 3 is different.

7.17.1 Mode 0

Putting either Timer into Mode 0 makes it look like an 8048 Timer, which is an 8-bit

Counter with a divide-by-32 prescaler. In this mode, the Timer register is configured as a

13-bit register. Mode 0 operation is the same for Timer 0 and Timer 1.

9397 750 14871

Product data sheet

Rev. 02 — 10 May 2005

© Koninklijke Philips Electronics N.V. 2005. All rights reserved.

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