Date   : Mon, 23 May 2005 00:38:53 +0100
From   : Philip Pemberton <philpem@...>
Subject: Re: 8-bit IDE i/f debugging

In message <050522235507@...>
          jgh@... (Jonathan Graham Harston) wrote:

> Wow! How did you do that? Just from the schematics, or are you the
> chap that bought the kit of parts from me at Wakefield?

I'm the chap that bought the kit of parts and also commented on the unusual
"squashed" 5.25" hard drive you had sitting on top of your Master :)

Had to dig through my spares box to find another 1k resistor though. That and
a couple of Y-cables to butcher (damn power supplies never have enough
connectors <grin>).

> I'm
> impressed you managed to build it 12 hours before I uploaded the
> assembly instructions! (I note from the headers that this message
> appears to have been posted late last night, just as I managed to
> stagger home and into bed :))

I spent another hour today debugging it with a logic analyser - "Hang on, why
are both chipselects active at the same time.. Oh, wait, CS3Fx is stuck
low.." 
That was fun.. ten minutes spent tracing the track and finding a suitable +5V
track.. then noticing the assembly instructions online after I'd finished :)

I think the universe is conspiring against me today - having the PSU filter
cap on the Master blow up and emit copious quantities of smoke was a little..
unusual to say the least. It's the first hardware failure I've ever had with
it (a few of the ASICs on the motherboard are socketed though - looks like
they may have been replaced at some time in the past). Nice machine - built
like a tank.

> Drive set as:
>   Master (not slave)
>   C (not D)
>   0 (not 1)
>   A (not B)
> *UNPLUG 13 to disable onboard ADFS, replacement ADFS ROM inserted
> *CONFIGURE HARD to enable hard drive access

Just done that - it works fine now. Now I just need to find a way to convince
*AForm to format a floppy in drive :4 (or find another ADFS formatter that'll
do it).

If you want to create a drive compatibility list, I'm using a Conner CFS425A
(left over after I put a 6GB Seagate in the RiscPC) as a single drive, and it
seems to be working fine with 208000K available.

Thanks,
-- 
Phil.                              | Acorn Risc PC600 Mk3, SA202, 64MB, 6GB,
philpem@...                        | ViewFinder, 10BaseT Ethernet, 2-slice,
http://www.philpem.me.uk/          | 48xCD, ARCINv6c IDE, SCSI
... Closing on ship target.  Music on!  Fire away!