Switching OTA slots

The code

Embedded C for Cortex-M. It compiles. There are 3 real bugs in it: the kind that pass a bench test and fail in the field.

void ota_finish(void)
{
    flash_erase(META_SECTOR);
    meta.active_slot = new_slot;
    meta.crc = crc32(&meta, sizeof meta);
    flash_write(META_SECTOR, &meta, sizeof meta);
    NVIC_SystemReset();
}

What an interviewer expects

• Point to each line you'd stop in a code review.
• Say what actually breaks: the failure mode, not just the rule it violates.
• Fix it, then defend the fix when asked the follow-up.

The bugs, reference fixes and the follow-up question are in the practice app, after you've tried it.

Companies that test this

Matched on the skills each company's embedded roles emphasise.

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