Checksum is a value calculated, by the programmer, from the data stream used to program the device. There is no specific checksum for a device, as this value is computed by the programmer from the code used to program the CPLD. Therefore, it will depend on the software algorithm used by the programmer. The checksum will change once the code is modified. This stored checksum value is compared to the one computed when the data is read back from the programmed device. If the two do not match, a checksum error is reported idicating that there was a programming error.
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