Hey thanks Kiste. I am currently doing a review of my hard disk, sd
card and fat32 libs. I understand that there are a few things that
need to be worked on. I also plan to add some type of error
notification if a sector is bad, or whatever the case is. Any help
would be appreciated.

For others listening. A hard disk's registers get addressed via a
parallel bus. I assume this bus runs some gates and maybe a shift
register. so it would be something like the following:
1. hard disk reads a sector into a sector buffer
2. I wait till data is ready by accessing the status register
3. I switch register address to the data register
4. send a read pulse
5. get the data from the bus.
6. repeat step 4 till end of sector

The problem is at step 4/5/6.It seems that the data doesn't get put
onto the bus fast enough on the hard disk end. Maybe there logic gates
in the hard disk that shift out the data or a shift register? In any
case, it is too slow for a 48mhz PIC.

I think we will need a 100ps delay. I know it is impossible to get an
accurate 100ps delay. The point would be to get as close to 100ps as
possible. Can we add a procedure to the delay library?

procedure delay_100ps() is
   pragma inline
   asm nop
end procedure

Matt.

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