Disable CMD_REBOOT: prevents agent death on serial boot mode#15
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Disable CMD_REBOOT: prevents agent death on serial boot mode#15
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Watchdog reset re-enters bootrom when boot pin is set to serial, requiring physical power cycle. Agent now rejects CMD_REBOOT with ACK_FLASH_ERROR. Python client.reboot() raises RuntimeError. Use selfupdate() to reload agent code without power cycle. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
After sf read, reads first 16 bytes via md.b and checks for garbage patterns (all-zeros, all-0xFF, all-0x55). Raises RuntimeError early instead of dumping megabytes of bad data. This catches cases where sf probe wasn't run or sf read failed silently, which produces uninitialized RAM content. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The boot log may contain flash size info (e.g. "16MB") which lets detect_flash() skip sf probe. But without sf probe in the current U-Boot session, the SPI subsystem isn't initialized and sf read silently writes nothing to RAM — producing a dump full of 0x55 (uninitialized DDR). Fix: always run sf probe 0 before sf read, regardless of how flash size was detected. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Transport errors (serial disconnect, timeout) now caught and retried up to 5 times per block instead of killing the entire dump. After each error, sends empty line to recover U-Boot prompt. Resume support: if output file already exists with partial data, continues from the last complete 4KB block boundary instead of starting over from scratch. Fixes: 1.5-hour dump lost at 87% due to transient serial error. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
sf read timeout increased from 30s to 120s to handle slow SPI clocks. Strict check for "Read: OK" in response — raises error instead of proceeding with potentially incomplete RAM data. Root cause of md.b dump corruption: sf read may have timed out before completing, leaving RAM with partial flash data + uninitialized 0xFF regions that md.b then dutifully dumped as "valid" data. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
7 new tests with MockTransport covering: - Sanity check catches all-0x55 and all-0xFF garbage - Sanity check passes valid ARM vector header - sf probe error raises RuntimeError - sf read without "Read: OK" raises RuntimeError - Resume from partial file skips completed blocks 34 total flashdump tests passing. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
Watchdog reset re-enters bootrom when boot pin is set to serial download mode, killing the agent with no way to recover except physical power cycle.
client.reboot()raises RuntimeError with explanationselfupdate()to reload agent code without power cycleContext
Discovered during flash dump verification — accidentally sent CMD_REBOOT, lost the agent, required power cycle to get it back.
Test plan
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