
Programmable Configuration Data
MVME7100ET Single Board Computer Programmer’s Reference (6806800K88B
)
74
for (index = 0; index < 32; index++)
{
crcValueFlipped <<= 1;
dataBitValue = crcValue & 1;
crcValue >>= 1;
crcValueF= dataBitValue;
}
crcValue = crcValueFlipped ^ 0xffffffff;
return (crcValue);
}
A.9.2
Serial Presence Detect Checksum Calculation
The calculation process is as follows:
1. Convert binary information, in byte locations 0 - 62, to decimal.
2. Add together (sum) all decimal values for addresses 0 - 62.
3. Divide sum by 256.
4. Convert remainder to binary (will be less than 256).
5. Store result (single byte) in address 63 as “Checksum”.
The same result can be obtained by adding the binary values in addresses 0 - 62 and eliminating
all but the low order byte. The low order byte is the “Checksum”.
Table A-3 Checksum Calculation Example
SPD Byte Address
Serial PD
Convert to Decimal
00 (0x00)
0010 0100
>
36
01 (0x01)
1111 1110
>
+ 254
02 (0x02)
0000 0000
>
+ 0
Summary of Contents for MVME7100ET
Page 1: ...MVME7100ET Single Board Computer Programmer s Reference P N 6806800K88B June 2014 ...
Page 10: ...MVME7100ET Single Board Computer Programmer s Reference 6806800K88B 10 List of Figures ...
Page 24: ...Memory Maps MVME7100ET Single Board Computer Programmer s Reference 6806800K88B 24 ...
Page 50: ...Register Descriptions MVME7100ET Single Board Computer Programmer s Reference 6806800K88B 50 ...
Page 96: ...Related Documentation MVME7100ET Single Board Computer Programmer s Reference 6806800K88B 96 ...
Page 97: ......