P89LPC901 PHILIPS [NXP Semiconductors], P89LPC901 Datasheet - Page 42

• 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
9397 750 12293
Product data
8.26.6 In-application programming
8.26.7 Using flash as data storage
8.26.8 User configuration bytes
8.26.9 User sector security bytes
In-Application Programming is performed in the application under the control of the
microcontroller’s firmware. The IAP facility consists of internal hardware resources to
facilitate programming and erasing. The Philips In-Application Programming has
made in-application programming in an embedded application possible without
additional components. This is accomplished through the use of four SFRs consisting
of a control/status register, a data register, and two address registers. Additional
details may be found in the P89LPC901/902/903 User’s Manual .
The Flash code memory array of this device supports individual byte erasing and
programming. Any byte in the code memory array may be read using the MOVC
instruction, provided that the sector containing the byte has not been secured (a
MOVC instruction is not allowed to read code memory contents of a secured sector).
Thus any byte in a non-secured sector may be used for non-volatile data storage.
Some user-configurable features of the P89LPC901/902/903 must be defined at
power-up and therefore cannot be set by the program after start of execution. These
features are configured through the use of the Flash byte UCFG1. Please see the
P89LPC901/902/903 User’s Manual for additional details.
There are four User Sector Security Bytes, each corresponding to one sector. Please
see the P89LPC901/902/903 User’s Manual for additional details.
Rev. 04 — 21 November 2003
8-bit microcontrollers with two-clock 80C51 core
P89LPC901/902/903
© Koninklijke Philips Electronics N.V. 2003. All rights reserved.
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