Hi Phill,
I produced a couple of Trump card clones in the 80's and still have the
PCB designs at hand, so drawing up a schematic will not be difficult. If
you can mail me the PLD dumps I'll label and comment the equations for
you. I did this myself, but cannot locate the files any more.
Malcolm Lear wrote:
Hi Phill,
I produced a couple of Trump card clones in the 80's and still have the
PCB designs at hand, so drawing up a schematic will not be difficult.
Excellent :)
If
you can mail me the PLD dumps I'll label and comment the equations for
you. I did this
Ah, that brings all the memories back. I'm sure the chips were protected
and I had to switch all combinations of input to deduce the equations.
The good news is that I can lay my hands on a board I manufactured and
read back the equations from that.
Unfortunately the earliest I can do that is
Malcolm Lear wrote:
Ah, that brings all the memories back. I'm sure the chips were protected
and I had to switch all combinations of input to deduce the equations.
I did wonder about that :) :) I may have a go at hooking them up to an
AVR and getting it to scan and record for me :) :)
The
Phill Harvey-Smith wrote:
Indeed, I have worked out this much, however I think the RAM test takes
place before this point so will hit the mirrored rom and only see 640K
:( So there must be something else afoot :)
RAM test is pretty much the first thing the OS does, long before
initializing the
Since the RAM on a standard QL was only ever intended to extend up to
$B, would the test ever go beyond that.
Cheers
Malcolm
On 21/02/2011 14:50, Phill Harvey-Smith wrote:
Malcolm Lear wrote:
Ah, that brings all the memories back. I'm sure the chips were
protected and I had to switch
Malcolm Lear wrote:
Since the RAM on a standard QL was only ever intended to extend up to
$B, would the test ever go beyond that.
Yep it does, loop only stops when it finds a location where it gets a
different value back than it wrote.
Cheers.
Phill.
Marcel Kilgus wrote:
Phill Harvey-Smith wrote:
Indeed, I have worked out this much, however I think the RAM test takes
place before this point so will hit the mirrored rom and only see 640K
:( So there must be something else afoot :)
RAM test is pretty much the first thing the OS does, long
