M30622M4 MITSUBISHI [Mitsubishi Electric Semiconductor], M30622M4 Datasheet - Page 165

• Manufacturer Part Number: M30622M4
• Description: SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
• Manufacturer: MITSUBISHI [Mitsubishi Electric Semiconductor]

CRC
Figure 1.22.3. Calculation example using the CRC calculation circuit
(1) Setting 0000
(2) Setting 01
(3) Setting 23
The code resulting from sending 01
(X
conformity with the modulo-2 operation.
Thus the CRC code becomes (1001 0001 1000 1000). Since the operation is in LSB first mode, the (1001 0001 1000 1000)
corresponds to 1189
circuit built in the M16C, switch between the LSB side and the MSB side of the input-holding bits, and carry out the CRC
operation. Also switch between the MSB and LSB of the result as stored in CRC data.
16
+ X
16
16
1 0001 0000 0010 0001
16
12
+ X
5
+ 1), becomes the remainder resulting from dividing (1000 0000) X
b15
b15
b15
16
in hexadecimal notation. If the CRC operation in MSB first mode is necessary in the CRC operation
LSB
9
1000 0000 0000 0000 0000 0000
1000 1000 0001 0000 1
1189
0A41
16
8
LSB
b7
in LSB first mode is (1000 0000). Thus the CRC code in the generating polynomial,
b7
16
1000 0001 0000 1000 0
1000 1000 0001 0000 1
16
1001 0001 1000 1000
1
1
b0
b0
b0
b0
b0
1000 1000
2 cycles
After CRC calculation is complete
CRC data register
Stores CRC code
After CRC calculation is complete
CRC data register
Stores CRC code
CRC data register CRCD
CRC input register
CRC input register
MSB
MSB
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
16
[03BD
CRCD
[03BD
CRCIN
[03BE
CRCIN
[03BE
CRCD
[03BD
by (1 0001 0000 0010 0001) in
16
16
16
16
16
Modulo-2 operation is
operation that complies
with the law given below.
, 03BC
]
, 03BC
]
, 03BC
16
16
16
0 + 0 = 0
0 + 1 = 1
1 + 0 = 1
1 + 1 = 0
]
]
]
-1 = 1
Mitsubishi microcomputers
M16C / 62 Group
165