p89v660 NXP Semiconductors, p89v660 Datasheet - Page 10

• Manufacturer Part Number: p89v660
• Description: P89v660/p89v662/p89v664 8-bit 80c51 5 V Low Power 16 Kb/32 Kb/64 Kb Flash Microcontroller With 512 B/1 Kb/2 Kb Ram, Dual I2c-bus, Spi
• Manufacturer: NXP Semiconductors

NXP Semiconductors
6. Functional description
P89V660_662_664_2
Product data sheet
6.1 Special function registers
Remark: SFR accesses are restricted in the following ways:
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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. 02 — 29 January 2008
80C51 with 512 B/1 kB/2 kB RAM, dual I
P89V660/662/664
© NXP B.V. 2008. All rights reserved.
2
C-bus, SPI
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