FastScan Test Pattern File Format

Test Pattern File Formats

 

 

CHAIN_TEST =

APPLY “test_setup” <value> <time>; PATTERN = <number>;

APPLY “scan_group_load_name” <time> = CHAIN “scan_chain_name1” = “values....”;

CHAIN “scan_chain_name2” = “values....”;

....

....

END;

APPLY “scan_group_unload_name” <time> = CHAIN “scan_chain_name1” = “values....”;

CHAIN “scan_chain_name2” = “values....”;

....

....

END;

END;

The optional “test_setup” line is applied at the beginning of the functional chain test pattern if there is a test_setup procedure in the Setup_Data section. The number for the pattern is a zero-based pattern number where a functional scan chain test for all scan chains in the circuit is to be tested. The scan group load and unload name and the scan chain name will be enclosed in double quotes. The values to load and unload the scan chain will be enclosed in double quotes.

During the loading of the scan chains, each value of the corresponding scan chain will be placed at its scan chain input pin. The shift procedure will shift the value through the scan chain and continue shifting the next value until all values for all the scan chains have been loaded. Since the number of shifts is determined by the length of the longest scan chain, X’s (don’t care) are placed at the beginning of the shorter scan chains. This will ensure that all the values of the scan chains will be loaded properly.

During the unloading of the scan chains, each value of the corresponding scan chain will be measured at its scan chain output pin. The shift procedure will shift the value out of the scan chain and continue shifting the next value until all values for all the scan chains have been unloaded. Again, since the number of shifts is determined by the length of the longest scan chain, X’s (don’t measure) are placed at the end of the shorter scan chains. This will ensure that all the values of the scan chains will be unloaded properly.

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FastScan and FlexTest Reference Manual, V8.6_4

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Mentor v8.6_4 manual Chaintest =