Good evening all... well, I can't start building my ZX80Core until the weekend, so I thought I'd have a play with something else.
Presenting... my attempt at recreating the original 8K BASIC keyboard overlay. I used Grant Searle's templates as a starting point, the various available images of the original e.g. from Sync and Rick Dickinson's gallery.
So what's the best way with these overlays? Get it printed as a mouse mat and then trim it - does that result in a nice matt plastic overlay? Or will it just fall apart lol
Do you have a rom giving read data and restore?
That would be a pre release and I really would like to have a copy of this, if possible.
I print them on good quality paper (not rough) and laminate this. I put this over the tactile switches for exchangebility between 4K and 8K ROM
Kind regards
Paul
In theory, there is no difference between theory and practice. But, in practice, there is.
Rich, yes but that would be for the 4K ROM. This is for the pre-production 8K, I made it because there only seemed to be low resolution versions available.
Ah sorry - what is the difference then?
I will see if I can sort out the hi-res version of the 4K ZX80 keyboard drawing for you tomorrow - it depends on how authentic to the original you want to be....
For example, a quick glance shows that the chequerboard patterns on your overlay are based on squares - that is very ZX81 (!) - the ZX80 keyboard uses circles believe it or not (with the top half / bottom half ones overlapping on the middle row of pixels!). I guess that was more to reflect the actual round pixels on screen....
Yes this is a marvellous idea.
Absolute great work!
And yes! I would love a copy of that rom image.
I am going to pm you my mail Adress!
Kind regards
Paul
In theory, there is no difference between theory and practice. But, in practice, there is.
Well, it turns out you can simulate having RESTORE with a line number by manipulating the DATADD system variable, as shown in the attached code... so not too bad. Of course, it would probably take only a few bytes to add the line number to the command like on a Spectrum, but my aim was to recreate the original ROM, and that did not support a line number on RESTORE. So, this is the kind of trick code we would have had to write!
What if the BYTE listing incorrectly missed off the variable argument for the RESTORE command when they went to press? _every_ read/restore/data implementation ever has the ability to set the line number... Perhaps it was implied
Hmmm..you can't specify a RESTORE line on a Dragon, and possibly not on a VIC 20 /C64 (dunno much about those)???? Looking at the above pics, surely to do that you must have got hold of the ROM file for this 'early' version...(or is it done with another modified ROM file.?) if so, where can we get it!!!!
