P89LPC920FDH PHILIPS [NXP Semiconductors], P89LPC920FDH Datasheet - Page 9

• Manufacturer Part Number: P89LPC920FDH
• Description: 8-bit microcontrollers with two-clock 80C51 core 2 kB/4 kB/8 kB 3 V low-power Flash with 256-byte data RAM
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
7. Special function registers
9397 750 14469
Product data
Remark: Special Function Registers (SFRs) accesses are restricted in the following
ways:
•
•
•
User must not attempt to access any SFR locations not defined.
Accesses to any defined SFR locations must be strictly for the functions for the
SFRs.
SFR bits labeled ‘-’, ‘0’ or ‘1’ can only be written and read as follows:
– ‘-’ Unless otherwise specified, must be written with ‘0’, but can return any value
– ‘0’ must be written with ‘0’, and will return a ‘0’ when read.
– ‘1’ must be written with ‘1’, and will return a ‘1’ when read.
when read (even if it was written with ‘0’). It is a reserved bit and may be used in
future derivatives.
Rev. 08 — 15 December 2004
P89LPC920/921/922/9221
8-bit microcontrollers with two-clock 80C51 core
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
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