Philips Semiconductors

User’s Manual - Preliminary -

 

 

 

 

 

 

FLASH PROGRAM MEMORY

P89LPC901/902/903

 

UCFG1

Address: xxxxh

Default: 63h

7

6

5

4

3

2

1

0

WDTE

RPE

BOE

WDSE

-

FOSC2

FOSC1

FOSC0

 

 

 

 

 

 

 

 

BIT

SYMBOL

FUNCTION

UCFG1.7

WDTE

Watchdog timer reset enable. When set =1, enables the watchdog timer reset. When

 

 

 

 

cleared = 0 , disables the watchdog timer reset. The timer may still be used to generate

 

 

 

 

an interrupt. Refer to Table 12-1 for details.

UCFG1.6

RPE

Reset pin enable. When set =1, enables the reset function of pin P1.5. When cleared, P1.5

 

 

 

 

may be used as an input pin. NOTE: During a power-up sequence, the RPE selection is

 

 

 

 

overriden and this pin will always functions as a reset input. After power-up the pin will

 

 

 

 

function 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.

UCFG1.5

BOE

Brownout Detect Enable (see section "Brownout Detection").

UCFG1.4

WDSE

Watchdog Safety Enable bit. Refer to Table for details.

UCFG1.3

 

-

 

Reserved (should remain unprogrammed at zero).

UCFG1.2-0

FOSC2-FSOC0

CPU oscillator type select. See section "Low Power Select (P89LPC901)" for additional

 

 

 

 

information. Combinations other than those shown below should not be used. They are

 

 

 

 

reserved for future use.When FOSC2:0 select either the internal RC or Watchdog

 

 

 

 

oscillators, the crystal oscillator configuration is controlled by RTCCON. See Table and

 

 

 

 

Table . Note: External clock input and crystal options are available on the

 

 

 

 

P89LPC901.

 

FOSC2-FOSC0

Oscillator Configuration

 

1

1

1

External clock input on XTAL1.

 

1

0

0

Watchdog Oscillator, 400KHz (+20/ -30% tolerance).

 

0

1

1

Internal RC oscillator, 7.373MHz ±2.5%.

 

0

1

0

Low frequency crystal, 20 kHz to 100 kHz.

 

0

0

1

Medium frequency crystal or resonator, 100 kHz to 4 MHz.

 

0

0

0

High frequency crystal or resonator, 4 MHz to 12 MHz.

Factory default value for UCFG1 is set for watchdog reset disabled, reset pin enabled, brownout detect enabled, and using the internal RC oscillator

Figure 14-7: Flash User Configuration Byte 1 (UCFG1)

2003 Dec 8

100

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Philips P89LPC903, P89LPC902 user manual UCFG1, P89LPC901
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P89LPC903, P89LPC902, P89LPC901 specifications

The Philips P89LPC901, P89LPC902, and P89LPC903 are a series of 8-bit microcontrollers designed for embedded system applications. These models, which belong to the LPC900 series, are notable for their affordability and versatility, making them an attractive choice for both hobbyists and professional developers.

One of the core features of the P89LPC901, P89LPC902, and P89LPC903 microcontrollers is their powerful 8-bit architecture. Operating at clock speeds up to 20 MHz, they deliver efficient performance suited for a range of tasks. Each model includes a comprehensive instruction set that supports various data manipulation and arithmetic functions, enabling extensive programming capabilities.

These microcontrollers come with built-in memory, with configurations that vary among the three models. The P89LPC901 typically features 4 KB of Flash memory and 256 bytes of RAM, while the P89LPC902 and P89LPC903 offer enhanced memory options. This Flash memory allows for reprogrammability, making it easier to update and modify applications as needed.

Another significant characteristic of the LPC900 series is their integrated peripherals. These models are equipped with a variety of I/O ports, allowing for easy interfacing with other devices and components. The P89LPC901 supports up to 32 I/O pins, while the P89LPC902 and P89LPC903 provide additional features such as analog-to-digital converters (ADCs), timers, and serial communication interfaces. This broad range of peripherals empowers developers to design complex applications without needing extra hardware.

Power consumption is also a key consideration for microcontroller applications. The P89LPC901, P89LPC902, and P89LPC903 are designed with low power consumption in mind, making them ideal for battery-operated devices and energy-efficient projects. They can operate in various power modes, allowing for greater flexibility in deployment.

In terms of technology, these microcontrollers utilize advanced CMOS technology, ensuring high reliability and durability. Their design offers a robust solution for numerous applications, including consumer electronics, industrial controls, and automation systems.

In summary, the Philips P89LPC901, P89LPC902, and P89LPC903 microcontrollers present an attractive combination of performance, integrated peripherals, low power consumption, and versatility. Their features cater to a wide array of applications, keeping them relevant in a rapidly evolving technology landscape. For hobbyists and professionals alike, these microcontrollers represent a reliable foundation for embedded system development.
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