5.3 Host Commands
(20) READ MULTIPLE (X’C4’)
The READ MULTIPLE Command performs the same as the READ SECTOR(S) Command except that when the device is ready to transfer data for a block of sectors, and enters the interrupt pending state only before the data transfer for the first sector of the block sectors. In the READ MULTIPLE command operation, the DRQ bit of the Status register is set only at the start of the data block, and is not set on each sector.
The number of sectors per block is defined by a successful SET MULTIPLE MODE Command. The SET MULTIPLE MODE command should be executed prior to the READ MULTIPLE command.
If the number of requested sectors is not divided evenly (having the same number of sectors [block count]), as many full blocks as possible are transferred, then a final partial block is transferred. The number of sectors in the partial block to be transferred is n where n = remainder of (“number of sectors”/”block count”).
If the READ MULTIPLE command is issued before the SET MULTIPLE MODE command is executed or when the READ MULTIPLE command is disabled, the device rejects the READ MULTIPLE command with an ABORTED COMMAND error.
Figure 5.2 shows an example of the execution of the READ MULTIPLE command.
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