Regarding SCSI READ Command

Question

I am trying to get Maximum LBA of the disk using SCSI Read Capacity Command.

I have created 10 byte CDB as follows

ccb->cam_flags = NO_DATA;  

ccb->cdb[0] = READ_CAPACITY;     /*  0x25 SCSI Opcode for Read Capacity Command */       ccb->cdb[1] = 0x01;

ccb->cdb[2] = 0;

ccb->cdb[3] = 0;

ccb->cdb[4] = 0;

ccb->cdb[5] = 0;

ccb->cdb[6] = 0;

ccb->cdb[7] = 0;

ccb->cdb[8] = 0x01;

ccb->cdb[9] = 0;

The SCSI command is successful. Unfortunately I am not getting the expected LBA and it is displaying it as zero.

My basic question is whether the SCSI CDB command created above is correct or not ?

Answer 1

Try to set ccb->cdb[1] to 0. Relative address bit should not be used in such case.