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FileCore Sector List
FileCore
» SWI Calls
» FileCore_DiscOp
» Sector List (use of)
Sector List (use of)
When bit 5 is set, the meaning of R3 (memory address) is altered. It doesn’t point to the area of RAM to or from which the disc data is to be transferred. Instead, it points to a word-aligned list of memory address/length pairs. All but the last of these lengths must be a multiple of the sector size. These word-pairs are used for the transfer until the total number of bytes given in R4 has been transferred.
On exit, R3 points to the first pair which wasn’t fully used, and this pair is updated to reflect the new start address/bytes remaining, so that a subsequent call would continue from where this call has finished.
This bit may only be set for reason codes 0-2.
See also
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