Renesas RH850: Software Trace FIFO Overflows
RH850 Software Trace uses a small FIFO that can easily overflow when too many trace messages are generated. This can cause sampling time to decrease or overflow error messages in the Analyzer Trace window (indicated by brown colored lines).
Possible solutions
Increase the LPD-4 clock
Open Hardware | CPU Options | SoC and increase the LPD clock until debugging works reliably. If the overflows still happen check the next possible solutions.
Generate fewer messages
This can be achieved in different ways, for example:
- Using shorter DBTAG (single 16-bit LPD frame) vs. bandwidth-hungry DBPUSH (sends three LPD frames) messages
- Short functions and tasks create more messages - avoid instrumenting them
- Using message filtering in winIDEA - it's possible to configure a filter to skip some high-frequent messages (check SFT Software Trace in winIDEA Help)
- Instrumenting sequences of two or multiple OS Runnables, instead of
instrumenting every Runnable individually, where applicable
Use an Emulation Adapter
Emulation Adapters for some RH850 devices utilize NEXUS or Aurora trace interface that is faster, thus enabling more trace data to be transferred off-chip for the same time frame without overflows.
Check out Knowledge Base article about Buffer (FIFO) overflows to see some generic solutions.