c8051f410 Silicon Laboratories, c8051f410 Datasheet - Page 121

• Manufacturer Part Number: c8051f410
• Description: 2.0 V, 32/16 Kb Flash, Smartclock, 12-bit Adc
• Manufacturer: Silicon Laboratories

14. Cyclic Redundancy Check Unit (CRC0)
C8051F41x devices include a cyclic redundancy check unit (CRC0) that can perform a CRC using a 16-bit
or 32-bit polynomial. CRC0 accepts a stream of 8-bit data written to the CRC0IN register. CRC0 posts the
16-bit or 32-bit result to an internal register. The internal result register may be accessed indirectly using
the CRC0PNT bits and CRC0DAT register, as shown in Figure 14.1. CRC0 also has a bit reverse register
for quick data manipulation.
14.1. CRC Algorithm
The C8051F41x CRC unit generates a CRC result equivalent to the following algorithm:
Step 1. XOR the input with the most-significant bytes of the current CRC result. If this is the first
Step 2a. If the MSB of the CRC result is set, shift the CRC result and XOR the result with the
Step 2b. If the MSB of the CRC result is not set, shift the CRC result.
Step 3. Repeat Steps 2a/2b for the number of input bits (8).
selected polynomial.
iteration of the CRC unit, the current CRC result will be the set initial value (0x00000000
or 0xFFFFFFFF).
CRC0PNT1
CRC0PNT0
CRC0SEL
CRC0INIT
CRC0VAL
Figure 14.1. CRC0 Block Diagram
CRC0IN
8
Rev. 1.0
CRC Engine
8
RESULT
4 to 1 MUX
8
32
8
8
8
C8051F410/1/2/3
CRC0DAT
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