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bilsch01 wrote:The command lines for writing them to disk are:

dd if=/mnt/sda5/home/bilsch/jinx/bootn1.bin count=1 of=/dev/sda1 count=1
dd if=/mnt/sda5/home/bilsch/jinx/kern1.bin count=1 of=/dev/sda1 seek=1 count=1

If you're using "count=1", you need to specify a block size and make sure that the files are smaller than the block size otherwise they will be truncated.

dd uses a default block size of 512 bytes.

Have you confirmed that /dev/sda1 starts at LBA 1 and not somewhere else?

[/quote]Hint: it probably doesn't.[/quote]

Yes. I corrected that. Sector to load is lba 64 not lba 2. I have the program running correctly now - Success. Onwards to writing a real bootsector and a format program. I,m going to model it on MSDOS. Thanks for your help. Bill S.

onlyonemac wrote:

bilsch01 wrote:The command lines for writing them to disk are:

dd if=/mnt/sda5/home/bilsch/jinx/bootn1.bin count=1 of=/dev/sda1 count=1
dd if=/mnt/sda5/home/bilsch/jinx/kern1.bin count=1 of=/dev/sda1 seek=1 count=1

If you're using "count=1", you need to specify a block size and make sure that the files are smaller than the block size otherwise they will be truncated.

Both files are 512 bytes. Default bs is 512.

bilsch01 wrote:I corrected that. Sector to load is lba 64 not lba 2. I have the program running correctly now - Success. Onwards to writing a real bootsector and a format program.

You really shouldn't hard code this value. Read the partition table to find where the partition starts.