C8051F930-TB Silicon Laboratories Inc, C8051F930-TB Datasheet - Page 164

• Manufacturer Part Number: C8051F930-TB
• Description: BOARD TARGET/PROTO W/C8051F930
• Manufacturer: Silicon Laboratories Inc
• Type: MCUr

Specifications of C8051F930-TB

• Contents: Board
• Processor To Be Evaluated: C8051F930
• Processor Series: C8051F9xx
• Data Bus Width: 8 bit
• Interface Type: I2C, UART, SPI
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Operating Supply Voltage: 0.9 V to 3.6 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: C8051F930
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 336-1472

C8051F93x-C8051F92x
15. Cyclic Redundancy Check Unit (CRC0)
C8051F93x-C8051F92x 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 15.1. CRC0 also has a bit
reverse register for quick data manipulation.
15.1. CRC Algorithm
The C8051F93x-C8051F92x CRC unit generates a CRC result equivalent to the following algorithm:
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1. XOR the input with the most-significant bits of the current CRC result. If this is the first iteration
2a. If the MSB of the CRC result is set, shift the CRC result and XOR the result with the selected
2b. If the MSB of the CRC result is not set, shift the CRC result. 
Repeat steps 2a/2b for the number of input bits (8). The algorithm is also described in the following
example. 
of the CRC unit, the current CRC result will be the set initial value 
(0x00000000 or 0xFFFFFFFF).
polynomial.
CRC0FLIP
CRC0FLIP
CRC0PNT1
CRC0PNT0
CRC0SEL
CRC0INIT
CRC0VAL
Write
Read
Figure 15.1. CRC0 Block Diagram
CRC0IN
8
CRC Engine
Rev. 1.1
8
8
RESULT
4 to 1 MUX
32
8
8
8
Automatic CRC
8
Controller
CRC0AUTO
CRC0DAT
CRC0CNT
Memory
Flash