I think there is a bitmap driver in the object exchange that works pretty well. I personally have been trying to write a VGA driver that would work similar to the TV drivers, but I haven't had any luck on that. But since the ZX has a color limitation, the bitmapped VGA drivers may work well for your project.
after some issue (http://forums.parallax.com/showthread.php?p=717850)·related to the VGA <-> HR512KSRAM pin compatibility, I am happy to announce that the prototype·one based on a TV driver is finished
Well.... don't expect to much from this prototype.. I am in a learning phase now
Anyway.. this feature are available:
- Format 64K of ram
- Load the 8k ZX81 Rom into the address $0000 - $1FFF
- Verify the loaded ROM
- Copy the 8k ZX81 Rom into the address $2000 - $3FFF ( this is how the memory map on a real ZX81 looks)
Next iterations:
Prototype two
- ROM hacks (patch the Load / Save Rom so that the zx81 games can be loaded and saved from/to the HR512KSRAM instead of the rom trying to use the tape via ULA)
- doKey (Map the ZX81 keyboard with the Hydra keyboard)
- Emulate 10 Z80 opcodes·and test it
My recommendation would be to emulate all the Z80 op codes first before you do any routines to load programs. Then when it can boot the system OS, that is when you should start focusing on running external programs.
Loading programs without a CPU core is really a waste, put most of your effort into the CPU core before anything else.
The Idea was to create a working ZX81 scheleton and then going into detail work. As I told before I am in a learning phase... and emulate all z80 opcodes I will get boring
ok, sorry to give you my support and direction, enjoy your journey of discovery [noparse]:D[/noparse] it's a fantastic journey for anyone, you will have a great time. [noparse]:)[/noparse]
I will still look forward to seeing the progress though.
k, I don't mind, was just helping, but glad to take a back seat too lol,
PS, I think sorry was me choosing the wrong wording, [noparse]:)[/noparse] meant to mean that I along with JTCook was just giving our support and knowledge, of ways to approach things.
and that with what we've learnt over our years of coding is that you'll be a LOT happier with the outcome when you run it and it boots up the OS, than doing a bit of it, then doing rom mods etc.
If you want true zx 81 emulation don't forget to add the funny shaped 16K ram pack with dodgy edge connector that resets the emulator everytime you get to inputting the very last line of fifty lines of code
Giemme, I've had a look at the code now [noparse]:D[/noparse]
Looks great and very tidy,
Just out of curiosity, are you going to convert it to PASM when you've finished it?
As my only criticisms are with all those calls, like getD getE etc, and spin is slow enough as it is, You'd need more than the 8* speed increase of the PropII to get it running at a decent speed.
Other than that, it's really shaping up well [noparse]:)[/noparse]
Has there been any progress on this since ZiCog has come out and preforms better then the actual Z80 chip.
It seems that the ZX81 and TS1000 emulators is one of the easiest to do(especially now thanks to heater) and would open up a bunch of software to use on the propeller.
Comments
I am using now following drivers and it works properly:
vga_1024x768_tile_driver_with_cursor.spin
vga_1024x1024_tile_driver_with_cursor.spin
Regards
Gianni
after some issue (http://forums.parallax.com/showthread.php?p=717850)·related to the VGA <-> HR512KSRAM pin compatibility, I am happy to announce that the prototype·one based on a TV driver is finished
Well.... don't expect to much from this prototype.. I am in a learning phase now
Anyway.. this feature are available:
- Format 64K of ram
- Load the 8k ZX81 Rom into the address $0000 - $1FFF
- Verify the loaded ROM
- Copy the 8k ZX81 Rom into the address $2000 - $3FFF ( this is how the memory map on a real ZX81 looks)
Next iterations:
Prototype two
- ROM hacks (patch the Load / Save Rom so that the zx81 games can be loaded and saved from/to the HR512KSRAM instead of the rom trying to use the tape via ULA)
- doKey (Map the ZX81 keyboard with the Hydra keyboard)
- Emulate 10 Z80 opcodes·and test it
Prototype three
- TapeLoad (FileNamePtr)
- TapeSave (FileNamePtr)
- Continue emulating opcodes
Prototype four
- Screen emulation
- Slow / Fast emulation
- conclude opcodes emulation.
Regards
Gianni
Post Edited (Giemme) : 4/1/2008 9:59:46 AM GMT
Loading programs without a CPU core is really a waste, put most of your effort into the CPU core before anything else.
Post Edited (JT Cook) : 4/1/2008 1:27:29 PM GMT
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http://www.propgfx.co.uk/forum/·home of the PropGFX Lite
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Regards
Gianni
I will still look forward to seeing the progress though.
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http://www.propgfx.co.uk/forum/·home of the PropGFX Lite
·
I can change my mind during my journey [noparse];)[/noparse]
Regards
Gianni
PS, I think sorry was me choosing the wrong wording, [noparse]:)[/noparse] meant to mean that I along with JTCook was just giving our support and knowledge, of ways to approach things.
and that with what we've learnt over our years of coding is that you'll be a LOT happier with the outcome when you run it and it boots up the OS, than doing a bit of it, then doing rom mods etc.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
http://www.propgfx.co.uk/forum/·home of the PropGFX Lite
·
here is an update of the z80 emulator project (not all command are emulated)
the scheleton of the zx81 is setup (see zx81 library)
all your comments are welcome
regards
Gianni
Looks great and very tidy,
Just out of curiosity, are you going to convert it to PASM when you've finished it?
As my only criticisms are with all those calls, like getD getE etc, and spin is slow enough as it is, You'd need more than the 8* speed increase of the PropII to get it running at a decent speed.
Other than that, it's really shaping up well [noparse]:)[/noparse]
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
http://www.propgfx.co.uk/forum/·home of the PropGFX Lite
·
Has there been any progress on this since ZiCog has come out and preforms better then the actual Z80 chip.
It seems that the ZX81 and TS1000 emulators is one of the easiest to do(especially now thanks to heater) and would open up a bunch of software to use on the propeller.
Thanks,
Doug
humanoido
Yes - ZiCog http://forums.parallax.com/showthread.php?p=788511