The DSKSYNC register is used to synchronize the input stream. This is highly useful when reading disks. If the WORDSYNC bit is enabled in ADKCON , no data is transferred until a word is found in the input stream that matches the word in the DSKSYNC register. On read, DMA will start with the following word from the disk. During disk read DMA, the controller will resync every time the word match is found. Typically the DSKSYNC will be set to the magic MFM sync mark value, $4489. In addition, the DSKSYNC bit in INTREQ is set when the input stream matches the DSKSYNC register. The DSKSYNC bit in INTREQ is independent of the WORDSYNC enable.
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