p89lpc904 NXP Semiconductors, p89lpc904 Datasheet - Page 8

• Manufacturer Part Number: p89lpc904
• Description: 8-bit Microcontrollers With Two-clock Accelerated 80c51 Core 1 Kb 3 V Byte-erasable Flash With 8-bit A/d Converter
• Manufacturer: NXP Semiconductors

Philips Semiconductors
7. Special function registers
9397 750 13521
Preliminary 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 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. 02 — 25 June 2004
8-bit microcontrollers with two-clock accelerated 80C51 core
© Koninklijke Philips Electronics N.V. 2004. All rights reserved.
P89LPC904
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