SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
To create tests that produce a unique signature, software must take care to ensure that the order of transactions (and resulting data/address phases) to a given MISR are consistent. Varying time between transactions does not affect the signature, because it is not updated on idle or not-ready cycles.
For cases that use a single initiator to access a given MISR, crossing asynchronous boundaries is acceptable. This is always true for ARP MISRs, but not necessarily for the WBUF MISRs.
For example if TC0 reads the OCP initiator bus and writes to WBUF MISR, the result is a consistent signature. And when TC0 reads EMIF address space (which is asynchronous) and writes to WBUF, while TC1 is also writing to WBUF results in different order of transactions.
For cases where all transactions/interactions are synchronous, using multiple initiators results in a consistent signature.