Zeddy emulator for ZX Spectrum

Emulator and emulator development specific topics
dr beep
Posts: 1296
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Zeddy emulator for ZX Spectrum

Post by dr beep »

It made me think about the ZX81-emulator.

I already made a new version that never was released and will never since the code is slower than the original
due to contented memory.

However if I alter the location of the emulator and set supporting routines in contented memory I will be able to win speed in
1) the emulation, faster selection due to mentioned routine which was NOT implemented and better access to relocated memory.
2) faster translated routines due to better access.

3) perhaps a quicker displayroutine due to new coding technics.

All together I think I can at 10% in speed.
User avatar
kokkiklhs
Posts: 55
Joined: Sat Jan 10, 2015 12:09 pm

Re: Zeddy emulator for ZX Spectrum

Post by kokkiklhs »

dr beep wrote:It made me think about the ZX81-emulator.

I already made a new version that never was released and will never since the code is slower than the original
due to contented memory.

However if I alter the location of the emulator and set supporting routines in contented memory I will be able to win speed in
1) the emulation, faster selection due to mentioned routine which was NOT implemented and better access to relocated memory.
2) faster translated routines due to better access.

3) perhaps a quicker displayroutine due to new coding technics.

All together I think I can at 10% in speed.
My speccy is eager to test it!!
8-)
Please let us know when you find some time to finish it with your magic coding skills!!
dr beep
Posts: 1296
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Zeddy emulator for ZX Spectrum

Post by dr beep »

kokkiklhs wrote:
dr beep wrote:It made me think about the ZX81-emulator.

I already made a new version that never was released and will never since the code is slower than the original
due to contented memory.

However if I alter the location of the emulator and set supporting routines in contented memory I will be able to win speed in
1) the emulation, faster selection due to mentioned routine which was NOT implemented and better access to relocated memory.
2) faster translated routines due to better access.

3) perhaps a quicker displayroutine due to new coding technics.

All together I think I can at 10% in speed.
My speccy is eager to test it!!
8-)
Please let us know when you find some time to finish it with your magic coding skills!!
First finish of game 29 in 1k hires.
dr beep
Posts: 1296
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Zeddy emulator for ZX Spectrum

Post by dr beep »

kokkiklhs wrote: Mon Nov 28, 2016 11:30 pm
dr beep wrote:It made me think about the ZX81-emulator.

I already made a new version that never was released and will never since the code is slower than the original
due to contented memory.

However if I alter the location of the emulator and set supporting routines in contented memory I will be able to win speed in
1) the emulation, faster selection due to mentioned routine which was NOT implemented and better access to relocated memory.
2) faster translated routines due to better access.

3) perhaps a quicker displayroutine due to new coding technics.

All together I think I can at 10% in speed.
My speccy is eager to test it!!
8-)
Please let us know when you find some time to finish it with your magic coding skills!!
Well, it is time... new emulator is released. See other topic.
User avatar
TMD2003
Posts: 10
Joined: Sun Oct 11, 2020 5:39 pm

Re: Zeddy emulator for ZX Spectrum

Post by TMD2003 »

I know this is quite an old thread, but this seems like an alternative method for what's been asked here, if a rather impractical one these days.

Out of curiosity I was looking through the first issue of Sinclair Projects, just to see what it was all about. Lots of soldering, EPROM burning, make your own joystick adapter... probably beyond the scope of me and my slightly shaky hand.

But I did notice an advert for a device that would, supposedly, allow a ZX81 program to be loaded into a Spectrum, with machine code routines that would convert SCROLL, UNPLOT, display file oddities, the non-ASCII character set and any other differences the ZX81 had, leaving only inverse video not dealt with. Given the fanaticism with which Sinclair people preserved all this old tech, right down to the last schematic, does anyone know if this survived?

Just out of interest.
Spectribution: Dr. Jim's Sinclair computing pages.
Features my own programs, modified type-ins, RZXs, character sets & UDGs, and QL type-ins... so far!
dr beep
Posts: 1296
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Zeddy emulator for ZX Spectrum

Post by dr beep »

TMD2003 wrote: Thu Oct 15, 2020 9:10 pm I know this is quite an old thread, but this seems like an alternative method for what's been asked here, if a rather impractical one these days.

Out of curiosity I was looking through the first issue of Sinclair Projects, just to see what it was all about. Lots of soldering, EPROM burning, make your own joystick adapter... probably beyond the scope of me and my slightly shaky hand.

But I did notice an advert for a device that would, supposedly, allow a ZX81 program to be loaded into a Spectrum, with machine code routines that would convert SCROLL, UNPLOT, display file oddities, the non-ASCII character set and any other differences the ZX81 had, leaving only inverse video not dealt with. Given the fanaticism with which Sinclair people preserved all this old tech, right down to the last schematic, does anyone know if this survived?

Just out of interest.
I only know SLOWLOADER which loads a ZX81 program and will add REM to the not working commands.
User avatar
Paul
Posts: 1101
Joined: Thu May 27, 2010 8:15 am
Location: Germanys west end

Re: Zeddy emulator for ZX Spectrum

Post by Paul »

dr beep wrote: Fri Oct 16, 2020 4:09 pm I only know SLOWLOADER which loads a ZX81 program and will add
REM to the not working commands.
Yes I had bought that as an original.
It worked quite well.
But as most programs for ZX81 had MC these would not work.
In theory, there is no difference between theory and practice. But, in practice, there is.
dr beep
Posts: 1296
Joined: Thu Jun 16, 2011 8:35 am
Location: Boxmeer

Re: Zeddy emulator for ZX Spectrum

Post by dr beep »

Paul wrote: Fri Oct 16, 2020 7:06 pm
dr beep wrote: Fri Oct 16, 2020 4:09 pm I only know SLOWLOADER which loads a ZX81 program and will add
REM to the not working commands.
Yes I had bought that as an original.
It worked quite well.
But as most programs for ZX81 had MC these would not work.
So an emulator (hardware or software) is the only solution.
Post Reply