M30626FJPFP#D5C Renesas Electronics America, M30626FJPFP#D5C Datasheet - Page 271

• Manufacturer Part Number: M30626FJPFP#D5C
• Description: MCU 3/5V 512K 100-QFP
• Manufacturer: Renesas Electronics America
• Series: M16C™ M16C/60r

Specifications of M30626FJPFP#D5C

• Core Processor: M16C/60
• Core Size: 16-Bit
• Speed: 24MHz
• Connectivity: I²C, IEBus, UART/USART
• Peripherals: DMA, WDT
• Number Of I /o: 85
• Program Memory Size: 512KB (512K x 8)
• Program Memory Type: FLASH
• Ram Size: 31K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 26x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 85°C
• Package / Case: 100-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

M16C/62P Group (M16C/62P, M16C/62PT)
Rev.2.41
REJ09B0185-0241
Figure 20.3
Setup procedure and CRC operation when generating CRC code “80C4h”
• CRC operation performed by the M16C
• Setting procedure
• Details of CRC operation
(1) Reverse the bit positions of the value “80C4h” by program in 1-byte units.
(2) Write 0000h (initial value)
(3) Write 01h
(4) Write 23h
Jan 10, 2006
CRC code: Remainder of a division in which the value written to the CRCIN register with its bit positions reversed is
Generator polynomial: X
As shown in (3) above, bit position of “01h” (00000001b) written to the CRCIN register is inversed and becomes
“10000000b”.
Add “1000 0000 0000 0000 0000 0000b”, as “10000000b” plus 16 digits, to “0000 0000 0000 0000 0000 0000b”,
as “0000 0000 0000 0000b” plus 8 digits as the default value of the CRCD register to perform the modulo-2 division.
“0001 0001 1000 1001b (1189h)”, the remainder “1001 0001 1000 1000b (9188h)” with inversed bit position, can
be read from the CRCD register.
When going on to (4) above, “23h (00100011b)” written in the CRCIN register is inversed and becomes
“11000100b”.
Add “1100 0100 0000 0000 0000 0000b”, as “11000100b” plus 16 digits, to “1001 0001 1000 1000 0000 0000b”, as
“1001 0001 1000 1000b” plus 8 digits as a remainder of (3) left in the CRCD register to perform the modulo-2 division.
“0000 1010 0100 0001b (0A41h)”, the remainder with inversed bit position, can be read from CRCD register.
“80h”
Generator polynomial
CRC Calculation
1 0001 0000 0010 0001 1000 0000 0000 0000 0000 0000
divided by the generator polynomial
“01h”, “C4h”
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16
+ X
12
“23h”
+ X
b15
b15
b15
5
1000 1000 0001 0000 1
+ 1 (1 0001 0000 0010 0001b)
CRC code
1000 0001 0000 1000 0
1000 1000 0001 0000 1
1001 0001 1000 1000
0A41h
1189h
b7
b7
1000 1000
b0
b0
b0
b0
b0
CRCD register
CRCIN register
CRCD register
CRCIN register
CRCD register
Two cycles later, the CRC code for “80h”, i.e.,
9188h, has its bit positions reversed to become
“1189h” which is stored in the CRCD register.
Two cycles later, the CRC code for “80C4h”, i.e.,
8250h, has its bit positions reversed to become
“0A41h” which is stored in the CRCD register.
Data
Modulo-2 operation is
operation that complies
with the law given below.
0 + 0 = 0
0 + 1 = 1
1 + 0 = 1
1 + 1 = 0
-1 = 1
20. CRC Calculation