Universal disk drive controller project - information needed!
Hello Speccy world!
I am a hardware developer from Russia and old Speccy fan. Currently i am starting a project aimed at joining Western and Eastern Speccy flavours at all.
I think it's a known problem that all of us use different disk systems, there are a lot of them around. They are often incompatible.
In addition, russian choice was BetaDisk with TR-DOS system which is very inflexible and has quite a poor API. This lead to that most of russian software use direct ROM calls for disk operations (there is no other way to operate without BASIC system) and this makes it from hard to impossible to adapt this software to foreign systems and spread it worldwide.
In addition, many of your titles are probably inaccessible for us, russians.
So the project was born to build a highly upgraded version of BetaDisk controller which could run ANY of existing disk systems for Speccy (at least most used ones). Currently this controller (Beta 2005 - a project working name) is supposed to be 100%-compatible with Beta128 at hardware level and compatible with other disk systems at API level.
This will be achieved by adding a reprogrammable memory mapper (in order to change ROM entrypoints) and 16 kb RAM to existing Beta128 controller. After this it will be able to run any TR-DOS version directly and modified versions of G+DOS, UniDOS and MDOS (hardware port addresses need to be changed).
At a second stage it is possible to expand RAM size in order to boot HDD-based operating systems (like MDOS3 and ResiDOS). It will not include IDE hardware because there are a lot of already existing solutions both in Russia and in other world.
Also this could solve a problem with hosting TR-DOS on an HDD. Again, the problem here is that not API but FDC calls need to be emulated (API is bad so games simply don't use it) using floppy images stored on an HDD. There is already a prototype of such a system working on two new russian Speccy clones (Turbo2+ and Pentagon1024), it works with floppy images stored in RAM and requires 1024kb of memory. Beta2005 would enable this solution for any other machine.
So my questions here are:
1. What disk systems are actually being used now?
2. What is the necessary implementation level (API calls, ROM routines or actual hardware) in order to run existing software for the system without modifying this software (in other words, how much software use direct ROM calls or direct FDC programming)?
3. +D, D80, etc page in their ROMs when the CPU goes to #0066 address (NMI). How many software uses this feature for something (by issuing CALL #0066)? There is a little problem with it because in Russia NMI is used by PC-compatible internal ISA modem connected to Speccy (with NMI handler bug fixed in ROM) so this entrypoint should be handled differently in order to provide compatibility with these systems.
P.S. I've already posted this message to "Miscellaneous", no one answered. What's up? Are there no real Speccy users, only emulator runners? Or no tech people here? Or noone needs such a device?
I am a hardware developer from Russia and old Speccy fan. Currently i am starting a project aimed at joining Western and Eastern Speccy flavours at all.
I think it's a known problem that all of us use different disk systems, there are a lot of them around. They are often incompatible.
In addition, russian choice was BetaDisk with TR-DOS system which is very inflexible and has quite a poor API. This lead to that most of russian software use direct ROM calls for disk operations (there is no other way to operate without BASIC system) and this makes it from hard to impossible to adapt this software to foreign systems and spread it worldwide.
In addition, many of your titles are probably inaccessible for us, russians.
So the project was born to build a highly upgraded version of BetaDisk controller which could run ANY of existing disk systems for Speccy (at least most used ones). Currently this controller (Beta 2005 - a project working name) is supposed to be 100%-compatible with Beta128 at hardware level and compatible with other disk systems at API level.
This will be achieved by adding a reprogrammable memory mapper (in order to change ROM entrypoints) and 16 kb RAM to existing Beta128 controller. After this it will be able to run any TR-DOS version directly and modified versions of G+DOS, UniDOS and MDOS (hardware port addresses need to be changed).
At a second stage it is possible to expand RAM size in order to boot HDD-based operating systems (like MDOS3 and ResiDOS). It will not include IDE hardware because there are a lot of already existing solutions both in Russia and in other world.
Also this could solve a problem with hosting TR-DOS on an HDD. Again, the problem here is that not API but FDC calls need to be emulated (API is bad so games simply don't use it) using floppy images stored on an HDD. There is already a prototype of such a system working on two new russian Speccy clones (Turbo2+ and Pentagon1024), it works with floppy images stored in RAM and requires 1024kb of memory. Beta2005 would enable this solution for any other machine.
So my questions here are:
1. What disk systems are actually being used now?
2. What is the necessary implementation level (API calls, ROM routines or actual hardware) in order to run existing software for the system without modifying this software (in other words, how much software use direct ROM calls or direct FDC programming)?
3. +D, D80, etc page in their ROMs when the CPU goes to #0066 address (NMI). How many software uses this feature for something (by issuing CALL #0066)? There is a little problem with it because in Russia NMI is used by PC-compatible internal ISA modem connected to Speccy (with NMI handler bug fixed in ROM) so this entrypoint should be handled differently in order to provide compatibility with these systems.
P.S. I've already posted this message to "Miscellaneous", no one answered. What's up? Are there no real Speccy users, only emulator runners? Or no tech people here? Or noone needs such a device?
Post edited by Sonic on
Comments
Disciple, Opus or PLUS D.
For the disciple you can get the complete
disassembly from this website.
http://www.thunderstats.com/clickout.cgi?http://www.biehold.nl/rudy/
Also available is the PLUS D
http://www.thunderstats.com/clickout.cgi?http://www.biehold.nl/rudy/
Special thanks for this goes to Rudy Biesma.
Its integration is much more difficult task because it's totally different from other DOSes. It is embedded into +3-BASIC (AFAIK) and this in fact suggests turning the computer into +3.
But it is possible to implement machine code calls of +3DOS (like ResiDOS does). Is there really any sense?