NXP Semiconductors
P89LPC932A1
8-bit microcontroller with accelerated two-clock 80C51 core
7. Functional description
Remark: Please refer to the P89LPC932A1 User manual for a more detailed functional
description.
7.1 Special function registers
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 ‘-’, logic 0 or logic 1 can only be written and read as follows:
– ‘-’ Unless otherwise specified, must be written with logic 0, but can return any
value when read (even if it was written with logic 0). It is a reserved bit and may be
used in future derivatives.
– Logic 0 must be written with logic 0, and will return a logic 0 when read.
– Logic 1 must be written with logic 1, and will return a logic 1 when read.
P89LPC932A1_3
Product data sheet
Rev. 03 — 12 March 2007
© NXP B.V. 2007. All rights reserved.
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