Re: PCcard (2)

jbevren_at_starbase.globalpc.net
Date: 2001-04-12 17:39:55

On Thu, 12 Apr 101 g.baltissen@hccnet.nl wrote:

> Hallo jbevren,
> 
> If I may ask, what is your real name?
> 
> > > Unfortunally I need 256 bytes for the window PLUS some bytes for I/O. An
> > > other solution is decrease the window to 128 bytes but I realy dislike 
> > that.
> > 
> > I dont know of ANY I/O boards that use more than 32 bytes actually.  I'd 
> > feel rather comfy iwht 128 bytes if we have dma-to-c64 in the future.
> 
> Then I have news for you: If you want DMA, you need that minimum 256 byte 
> window. As I already said, I intend to use the 8237. It drives A0..7 
> directly, A8..15 is driven thru a latch. Driving A7 thru a latch as well 
> only complicates things.

Um, no, you don tneed the wide window ;)  The 8237 register set is NOT more
than 32 bytes, and DMA has nothing to do with I/O windows ;)

> 
> > Grow up.  Throw the FC3 out the window like I did. ;)
> 
> I hardly use it but being a techie I opened it and noticed this behaviour. 
> And as a techie I dislike this solution. It had been much more nicer to use 
> an extra decoder so one could combine this cart with others.

Its like the (similarly) unfriendly epyx fastload cart I sometimes use on my
non-scpu system. ;)

> 
> > This is, again, an internal mod ;)
> 
> You cannot blame me using a hack because others messed up first. Even 
> Commodore is to blame because the REU needs less then 16 bytes but due to 
> mirroring, no one else can use (a part of) the other 240 bytes :(

I dont, really.  I woudl LOVE to re-do the internal I/O decoding.  Bogax and
I are working on a new form factor for the c64 board, which will have
cleanly decoded I/O.  That's another topic, however, so I wont get into it
here

> 
> > I'd rather collaborate and make a design the two of us can agree on
> > ...
> > If we can stay outside, and work from the cart port, we can get much more 
> > support from the scene.
> 
> As already mentioned, my design will use the the I/O-lines in the first 
> place. And you may tell me what IO-line to use for what part :) 
> The connection is made using two jumpers. If one intends to use other base 
> addresses, (s)he only needs to connect these pins to the outputs of the 
> used decoders. 
> Until now all my software is freeware, including the sources. This enables 
> one to compile its own version. 
> 
> But if someone decides to write non-public SW for the standard IO-lines, 
> then the above person simply has bad luck :(

That someone is plain silly ;)

> 
> How does this sound to you?

Hmz.  Sounds good.  Have you read my post about the pcb under the sid?

> 
> > the CIA is at dc00 and dd00.  D700? look at the top of the file. ;)
> 
> I understand you would agree on $D7xx as well. Then this could be my 256 
> byte window. Then I need another 8 bytes for the I/O. Use an extra decoder 
> with one of the CIA's et voila, I have my extra bytes.
> 
> Then I have a question: is there a list where you can see which I/O-cart 
> use which address?
> And then for the SCPU-users: what I/O-addresses does the SCPU use 
> (including possible mirroring)? 
> 
> Groetjes, Ruud
> 
> http://Ruud.C64.org/
> 
> 
> 
> -
> This message was sent through the cbm-hackers mailing list.
> To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tml.hut.fi.
> 

-
This message was sent through the cbm-hackers mailing list.
To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tml.hut.fi.

Archive generated by hypermail 2.1.1.