Embedded Systems — question 6 of 10
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This is a classic hardware/software boundary bug that appears as soon as DMA is combined with any kind of double-use buffer.
You set up a DMA channel to fill a 256-byte buffer from an ADC in circular mode, with an interrupt firing on transfer-complete to process the data. Occasionally the processed data looks like a mix of old and new samples, as if you read the buffer mid-transfer. Walk me through the likely causes and how you'd fix it.