🚀 go-pugleaf

Before I here read the discussion about the harddisk startup
procedure I tried to solve the Problem. I think I can contribute
some facts.

All four SH204 Harddisks I know answer to the Test Unit Ready
command. Since months I have an own program similar SHIP.PRG
which parks the harddisk and loops with Test Unit Ready until
the harddisk is switched off.
So I tried the following: Write a bootsector for A: which loops
with Test Unit Ready until the harddisk answers, then returns
and let the ST read the bootsector of C:. On my SH204 at home
that worked fine and I was very proud having solved the problem.
Also the COLDSTRT.ACC method proposed here worked.
But (!) with two other SH204 both methods failed. So at last
I tried a bootsector which only waits half a minute - the
Test Unit Ready could have disturbed the spinup. But no,
these two SH204 did not spinup, even a reset didnt help, I had
to swich off. Apparently, as Mr.Pratt suggested, the reset
instruction in ROM start disturbs some harddisks and some as mine
endure even a looping Test Unit Ready at spinup.
When spinnig up it does not answer and then all status bits are zero.

      Kloppenburg@kmx.gmd.dbp.de
UUCP: kloppen@gmdzi
                    In real life: Jelske Kloppenburg.