M32CSLASH86 datasheet(280/505 Pages) RENESAS

280 / 505 page

Page 257

20. CRC Calculation

)

(

8 low-order bits

8 high-

order bits

High-order bits of data bus

Low-order bits of data bus

CRCD register

CRCIN register

CRC code generation circuit

x16 + x12 + x5 + 1

Setting Range

CRC Data Register

Function

Symbol

Address

After Reset

CRCD

037D16- 037C16

Indeterminate

000016 to FFFF16

After default value is written to the CRCD

CRCD register by writing data to the CRCIN

inversed. The inversed value is read as the CRC

code.

b15

Setting Range

CRC Input Register

Function

Symbol

Address

After Reset

CRCIN

037E16

Indeterminate

Data input.

Inverse bit position of data.

0016 to FF16

20. CRC Calculation

The CRC (Cyclic Redundancy Check) calculation detects an error in data blocks. A generator polynomial

of CRC_CCITT (X16 + X12 + X5 + 1) generates CRC code.

The CRC code is a 16-bit code generated for a block of data of desired length. This block of data is in 8-bit

units.The CRC code is set in the CRCD register every time one-byte data is transferred to the CRCIN

completed in two cycles.

Figure 20.1 shows a block diagram of a CRC circuit. Figure 20.2 shows CRC-associated registers. Figure

20.3 shows an example of the CRC calculation.

Figure 20.1 CRC Calculation Block Diagram

Figure 20.2 CRCD Register and CRCIN Register

M32C/86 bảng dữ liệu(PDF) 280 Page - Renesas Technology Corp

M32C/86 bảng dữ liệu(HTML) 280 Page - Renesas Technology Corp

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

bảng dữ liệu tải về

Link URL