[sebhc] H89 BOOT SUCCESS

[Lee Hart]

dwight elvey wrote:
> I can read from the disk without error but as soon as the disk is
> written, it can no longer be read from. I've seen this several
> times and even experimented a little, to varify this.
> I suspect that the frequency is not high enough to get through
> the preamps on the drives. The read heads are only looking for
> sharp transisions.

It could be a simple as that for read, you get many chances, but for 
write, only one.

The BIOS automatically retries during reads until it gets an error-free 
sector; it might take up to 10 tries before you get a BDOS error 
message. All the user notices is that reads seem a little slow.

But on write, you only need one bad bit and the sector is unreadable, no 
matter how many times you re-read it.

-- 
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in    --    Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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