FoxESS
MDSP SPI Fault

DSP Internal Communication Fault

Serial communication between master DSP and slave DSP (or manager board) has failed. H1(G2) internal hardware/firmware issue.

Firmware version mismatch between internal boardsTransient communication errorInternal board hardware fault
STEP 1
Power cycle inverter. Check firmware in Fox Cloud -- all boards should be on the same release. Update via USB if outdated
STEP 2
If firmware is current, check for power supply instability (loose AC connection, voltage fluctuations at supply)
Persists after power cycle and firmware update — board fault, escalate
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