p89lpc932ba NXP Semiconductors, p89lpc932ba Datasheet - Page 26

• Manufacturer Part Number: p89lpc932ba
• Description: P89lpc932 8-bit Microcontroller With Accelerated Two-clock 80c51 Core 8 Kb Flash With 512-byte Data Eeprom And 768-byte Ram
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 12379
Product data
8.16.1 Mode 0
8.16.2 Mode 1
8.16.3 Mode 2
8.16.4 Mode 3
8.16.5 Mode 6
8.16.6 Timer overflow toggle output
8.16 Timers/counters 0 and 1
The P89LPC932 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.
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.
Mode 1 is the same as Mode 0, except that all 16 bits of the timer register are used.
Mode 2 configures the Timer register as an 8-bit Counter with automatic reload.
Mode 2 operation is the same for Timer 0 and Timer 1.
When Timer 1 is in Mode 3 it is stopped. Timer 0 in Mode 3 forms two separate 8-bit
counters and is provided for applications that require an extra 8-bit timer. When
Timer 1 is in Mode 3 it can still be used by the serial port as a baud rate generator.
In this mode, the corresponding timer can be changed to a PWM with a full period of
256 timer clocks.
Timers 0 and 1 can be configured to automatically toggle a port output whenever a
timer overflow occurs. The same device pins that are used for the T0 and T1 count
inputs are also used for the timer toggle outputs. The port outputs will be a logic 1
prior to the first timer overflow when this mode is turned on.
Rev. 04 — 06 January 2004
8-bit microcontroller with accelerated two-clock 80C51 core
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
P89LPC932
26 of 60