Answers Database
CPLD: XC9500: Difference between all the checksums for the XC9500 family
Record #3214
Product Family: Hardware
Product Line: 9500
Product Part: 9500
Problem Title:
CPLD: XC9500: Difference between all the checksums for the XC9500 family
Problem Description:
Urgency: Standard
General Description:
There are three different checksums associated with the XC9500
devices. What are they?
Solution 1:
The XC9500 JEDEC files have two checksums as defined by the JEDEC
standard. The last line in the JEDEC file beginning with the ^C
character is the file checksum. The second to last line in the
JEDEC file beginning with a C and ending with an * is the fuse
checksum.
The JEDEC file checksum is the sum of only the actual programmed
bit locations in the device adjusted into eight bits (as
specified in the JEDEC file). The JEDEC checksum is therefore
missing some device bit locations in its calculated checksum.
The EZTag/JTAG Programmer softwares report a third checksum, which
is actually a sum of all the eight bit programmed bytes in the
device (as read back directly from the device without any
adjustments). This checksum includes all the programmable bits in
the device and is completely different from the JEDEC file
checksum.
End of Record #3214 - Last Modified: 12/20/99 10:10 |
