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NAME
TD_SEEK/ETD_SEEK - control positioning of the drive heads.
FUNCTION
These commands are currently provided for internal diagnostics, disk repair, and head cleaning only.
TD_SEEK and ETD_SEEK move the drive heads to the track specified. The io_Offset field should be set to the (byte) offset to which the seek is to occur. TD_SEEK and ETD_SEEK do not verify their position until the next read. That is, they only move the heads; they do not actually read any data.
TD_SEEK and ETD_SEEK move the drive heads to the track specified. The io_Offset field should be set to the (byte) offset to which the seek is to occur. TD_SEEK and ETD_SEEK do not verify their position until the next read. That is, they only move the heads; they do not actually read any data.
INPUTS
- io_Device
-
preset by the call to OpenDevice()
- io_Unit
-
preset by the call to OpenDevice()
- io_Command
-
TD_SEEK or ETD_SEEK
- io_Flags
-
0 or IOF_QUICK
- io_Offset
-
byte offset from the start of the disk describing where to move the head to.
- iotd_Count
-
(ETD_SEEK only) maximum allowable change counter value.
RESULT
- io_Error
-
0 for success, or an error code as defined in <devices/trackdisk.h>