Re: New firmware for PseudoDisk / some problems

[dempson@actrix.gen.nz (David Empson)]

Alex Freed <alexf@mirrow.com> wrote:

> First of all, thank you, David Empson. That was it.
> I replaced the string and char output functions and it works like a charm.

Excellent.

> I was holding two payed-for boards in the hope to ship better firmware.
> Now looks ready to go after a few tests.
> 
> I understand that booting by typing PR#4 caused an infinite loop. What is
> less clear to me is why cold boot failed too. Just curious.

Do you mean auto starting with your card as the "disk controller" in the
highest slot (Ctrl-Apple-Reset on a //e or later)?

Perhaps you are trying to call something which is not initialized after
a cold boot. For example, the monitor's INIT routine should be called
before attempting to use any of its text output routines, or your text
window, line pointers, vertical and horizontal position and I/O vectors
might contain garbage. This will have been done already if you got into
BASIC then booted your card with C400G or PR#4.

> Polymorph <polymorph69@hotmail.com> wrote: 
> > How are the sales going? I'm still very close to putting in an order
> > (if I'm not too late)...
> 
> Sales are very slow. The first run of 20 boards will probably take a while
> to sell, and I doubt I'll order more PCBs after that.

I would potentially be interested in buying one if I had spare money
lying around, but I have more important things like rent that needs to
be paid.

I might at least be able to contribute to the project on the
software/firmware side of things - I've developed firmware for Apple II
slot cards (e.g. disassembled the NESTAR network interface card firmware
and added a ProDOS block driver to it), built my own simple I/O card
(including a PIA, VIA and ACIA, I think) and I work in the embedded
system field so I'm very familiar with the concepts. (Not to mention my
many years of dabbling with the Apple II, particularly the IIe and
IIgs.)

I would like to see a detailed technical overview of the card (out of
academic curiosity if nothing else). One point which interests me: is
your CPLD/FPGA hooked up to all the Apple II bus signals, in particular
does it have enough logic to potentially support the IOSTROBE signal and
allow the use of the $C800-$CFFF region (including decoding an access to
$CFFF so it can release a latch)? If so, there is the potential of
adding a Smartport driver to the card firmware, which would give it more
flexibility than a ProDOS block driver.

I don't think there would be enough space in the $Cn00 area to implement
a SmartPort interface, as it requires quite a lot of code to interact
with parameter blocks in main RAM. Adding 2 KB in the $C800 space will
be plenty - the Superdrive card easily manages it, and it has a similar
design with a processor on the card which does all the heavy lifting.

If I am going to contribute more effectively, I'll have to dig some of
my books out of the basement. First I'll need some shelf space. Then I
have to find which box they are in.

-- 
David Empson
dempson@actrix.gen.nz