Hi guys,
to avoid confusion and/or also going off topic in that thread where I was asking about that Microworld Basic I decided to start a new one.
So the story goes more or less like "years ago someone gave me a bag full of weird chips, some where exotic CPUs, to preserve the memory of all this and learn new things from old stuff I embarked on a mission of 'one computer per cpu', this is my SG2650 design".
Must said, when I started all that I did some research but could not find immediately how popular this processor was in Australia nor I did not know very much about other systems, all I found out was the datasheet and some mention of the PIPBUG then I think someway later I found about Arcadia central or such and managed to find some extra documentation and an assembler.
This project been born with the idea of "do something that works that can be still someway useful but with minimal components", it's also been an experiment of mine about finding out "some ways to do things at home", I've done this stuff bits at time during ( little ) free time all with home tools and some .. really OLD tools ..
Anyway I've done my best to document it and put together this PDF ( edited in LATex ) which describes as best ( for now ) the system.
The system is pretty basic, the choice of some chips been literally because "that's what I had at hands" , to save space on board and such ( and to learn more about VHDL ) most of the logic functions been compressed into a single XC9572 CPLD.
If you read the PDF you should be able to make your own mind and use it as a reference/starting point to make your own, this board does not try to emulate or be compatible or such with anything else but it's not "too different" from other stuff I've seen.
The IDE interface, I haven't tested it yet, it's based around Phil's ( Retroleum ) IDE interface, it's nothing special really, it's just a way to write/read 16 bits data from an 8 bits bus by splitting it in two halves and generate a few signals with the correct timings for the IDE protocol.
If you don't care about it you can simply ignore it and make the project even simpler.
Anyway even as it is the board works, you can get to a system where you can do some stuff in it and upload code and run it via XMODEM, I normally use some program like TeraTerm for that and/or my faithful VT220.
This project is for "fun" and "self teaching/learning" there's absolutely NO commercial or such intention whatsoever, it's not even "perfect" or such, it certainly has some defects, it can be optimized, it could have been done better and such but .. "improve it as you like".
In short, here is the PDF, maybe I'll update it a little ( I'll let you know if I do ), enjoy it, make a good use of it, if you want to ask something about maybe do it here on the thread.
Here is the PDF describing the system.
I hope it will be an interesting and useful thing to read.
If you make some other SG2650 systems please let me know and post something here
My next plans for it is :
- test the IDE interface
- have some BASIC working
Enjoy !
to avoid confusion and/or also going off topic in that thread where I was asking about that Microworld Basic I decided to start a new one.
So the story goes more or less like "years ago someone gave me a bag full of weird chips, some where exotic CPUs, to preserve the memory of all this and learn new things from old stuff I embarked on a mission of 'one computer per cpu', this is my SG2650 design".
Must said, when I started all that I did some research but could not find immediately how popular this processor was in Australia nor I did not know very much about other systems, all I found out was the datasheet and some mention of the PIPBUG then I think someway later I found about Arcadia central or such and managed to find some extra documentation and an assembler.
This project been born with the idea of "do something that works that can be still someway useful but with minimal components", it's also been an experiment of mine about finding out "some ways to do things at home", I've done this stuff bits at time during ( little ) free time all with home tools and some .. really OLD tools ..
Anyway I've done my best to document it and put together this PDF ( edited in LATex ) which describes as best ( for now ) the system.
The system is pretty basic, the choice of some chips been literally because "that's what I had at hands" , to save space on board and such ( and to learn more about VHDL ) most of the logic functions been compressed into a single XC9572 CPLD.
If you read the PDF you should be able to make your own mind and use it as a reference/starting point to make your own, this board does not try to emulate or be compatible or such with anything else but it's not "too different" from other stuff I've seen.
The IDE interface, I haven't tested it yet, it's based around Phil's ( Retroleum ) IDE interface, it's nothing special really, it's just a way to write/read 16 bits data from an 8 bits bus by splitting it in two halves and generate a few signals with the correct timings for the IDE protocol.
If you don't care about it you can simply ignore it and make the project even simpler.
Anyway even as it is the board works, you can get to a system where you can do some stuff in it and upload code and run it via XMODEM, I normally use some program like TeraTerm for that and/or my faithful VT220.
This project is for "fun" and "self teaching/learning" there's absolutely NO commercial or such intention whatsoever, it's not even "perfect" or such, it certainly has some defects, it can be optimized, it could have been done better and such but .. "improve it as you like".
In short, here is the PDF, maybe I'll update it a little ( I'll let you know if I do ), enjoy it, make a good use of it, if you want to ask something about maybe do it here on the thread.
Here is the PDF describing the system.
I hope it will be an interesting and useful thing to read.
If you make some other SG2650 systems please let me know and post something here
My next plans for it is :
- test the IDE interface
- have some BASIC working
Enjoy !