Accesses to the registers follow these rules:
- If both the CPU and CLA request access at the
same time, then the CLA has priority and the main CPU is stalled.
- If a CPU access is in-progress and another CPU
access is pending, then the CLA has priority over the pending CPU access. In
this case, the CLA access begins when the current CPU access completes.
- While a CPU access is in-progress, any incoming
CLA access is stalled.
- While a CLA access is in-progress, any incoming
CPU access is stalled.
- A CPU write operation has priority over a CPU read operation.
- A CLA write operation has priority over a CLA read operation.
- If the CPU is performing a read-modify-write
operation and the CLA performs a write to the same location, the CLA write
can be lost if the operation occurs in-between the CPU read and write. For
this reason, do not mix CPU and CLA accesses to same location.