Hardware upgrade for the Oric?

This is the right place to discuss on how to implement hardware vsync, adding a VIA or AY chipset, puting multiple roms, or how to design a new flash expansion card.
mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Fri Oct 05, 2007 11:12 am

Yes I even recall an MMC article in GNU/Linux Magazine French, with code for a uP and a Linux driver for a cheapo parallel port interface. They even made their own cheapo mmc connector.
It could be a good idea to use the ROM socket to limit the number of soldering, but do all revs have sockets ?
Btw, I noticed the printer port on my Atmos is not really aligned with the exp port, it's closer to the board, and leaves a large hole (3mm) on all its width up to the case. Not sure it's common, but it's probably enough to fit an mmc... maybe even a compact flash ? :P

However I like better external interfaces that don't require modding the internals. Plus I want other things on the board.
I was thinking more of a "stratmos" ext board, in a nice hand made red&black case :)

JamesD
Flight Lieutenant
Posts: 354
Joined: Tue Nov 07, 2006 7:38 am

Post by JamesD » Sat Oct 06, 2007 2:24 am

Well... the purpose was more to provide a better environment for developers than to rebuild the stratos.

The goals:
1. Make the overlay memory available without having to attach an external drive (which are rare).
2. Add fast random access storage to replace the disk drive (did I mention they are rare?) so that more people can run the new games.
3. Add a serial port so data can be sent back and forth between an ORIC and a PC for development and for people that just want to load software on to their machine.
4. Add more ROM (In this case FLASH) to hold the DOS for the SD interface.

Really, the circuit could fit internally or externally. It will probably consist of 2 PLDs for internal or possibly 1 for external, 1 FLASH memory, an SD socket and place to connect a cable to the serial connector.
Maybe even add some RAM if there is room.

If I set out to building a Stratos it will be in an FPGA and I have way too many projects in the works to even think about it.

Oh, and I really don't care if all revs have sockets. Mine is an issue 3 and it has sockets and it's what is most important to me. :D
But... since I think all connections are available externally it's a moot point.

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 3:36 am

It's just about adding what's missing on an atmos to behave like a stratos:
- serial port (always better if it's compatible, single driver)
- 2nd VIA, always handy, + standard way of enabling overlay + rom banks
- joystick+mouse
- more rom
- maybe disk controller... can always be swapped.
So it's not that different.

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 3:44 am

As for DOS, there is a nice thread there.

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 3:49 am

Of course if I really wanted to make a new box I'd rather make an 65816-based ORIC IIGS with 16MB of RAM :D

JamesD
Flight Lieutenant
Posts: 354
Joined: Tue Nov 07, 2006 7:38 am

Post by JamesD » Sat Oct 06, 2007 3:54 am

mmu_man wrote:Of course if I really wanted to make a new box I'd rather make an 65816-based ORIC IIGS with 16MB of RAM :D
LOL, have you been reading a thread on the Atari Age forums I've been posting in?

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 4:01 am

Oh, of course on the wish-list I could add things like ADB or PS/2 converter for the mouse, network card for contiki, RTC, ...
It should be possible to design things in a modular enough way so one could pick up only part of the board he wants. Maybe even plugable cards à la Apple II... I read about it, it had very clever ways to handle card-specific ROM... mapped 256 bytes + common area remapped depending on which card rom the opcode calls from (likely last-address-based bank switching).
Oh, of course having the whole thing battery-able + LCD would make a laptoric :)
Hmm it's time to sleep as I'm dreaming already.

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 4:02 am

JamesD wrote:LOL, have you been reading a thread on the Atari Age forums I've been posting in?
Not at all, but I read lots of Apple II history stuff this week... the IIGS design seems interesting.

JamesD
Flight Lieutenant
Posts: 354
Joined: Tue Nov 07, 2006 7:38 am

Post by JamesD » Sat Oct 06, 2007 4:20 am

mmu_man wrote:It's just about adding what's missing on an atmos to behave like a stratos:
- serial port (always better if it's compatible, single driver)
- 2nd VIA, always handy, + standard way of enabling overlay + rom banks
- joystick+mouse
- more rom
- maybe disk controller... can always be swapped.
So it's not that different.
Yes, well I don't think you quite understand.

I am not a hardware guru. I have some hardware design training but I was a CS major. I have designed some hardware in the past and I understand digital logic well but anything that requires complex timing or that isn't something I already have source for and it would be a bit of a stretch at this point.

I know just enough verilog and VHDL to follow some of the logic and I could probably write enough for this project. I want to build computers in FPGAs but it's a good idea to start small. Dealing with a handful of mistakes is a lot easier than hundreds or thousands.

A simple PC board where you connect traces to parts is relatively easy. Given the schematic of the ORIC and info on the stratos I could probably do a good portion of the layout for an add on board with little difficulty. But if the parts don't exist it's a whole different thing. Getting all the old parts like the VIA and floppy controller would be a problem and the only alternative is an FPGA. Not only that but there is probably some analog circuitry involved in the floppy controller and I don't know enough about analog circuits to even know where to begin.

Serial port.... I'm not sure this one will even have an adjustable baud rate so it stays small to fit in the smallest (and cheapest) PLD possible. I also have source code. To be honest I figured the serial port will allow a drive to be emulated over the connection by a PC (great for the development part) or to just run a transfer utility. That's it.
If anything it should be at a different address just so it doesn't interfere with the stratos serial port in case someone decides to add one.

JamesD
Flight Lieutenant
Posts: 354
Joined: Tue Nov 07, 2006 7:38 am

Post by JamesD » Sat Oct 06, 2007 5:54 am

BTW, I haven't been able to find any pictures of an ORIC motherboard that doesn't have the ROMs and ULA socketed.
The Telestrat is too different for me to worry about but if it has the same ULA and a space for two ROMs then it would probably fit in it as well.
http://www.48katmos.freeuk.com/oric1.htm
http://www.48katmos.freeuk.com/origoric.jpg

Some machines appear to have only one ROM where other ones like mine have two ROMs. However they still have the place for the 2nd ROM. Mine even has the hand labeled ROMs.
http://www.48katmos.freeuk.com/roms.htm

JamesD
Flight Lieutenant
Posts: 354
Joined: Tue Nov 07, 2006 7:38 am

Post by JamesD » Sat Oct 06, 2007 6:14 am

mmu_man wrote:
JamesD wrote:LOL, have you been reading a thread on the Atari Age forums I've been posting in?
Not at all, but I read lots of Apple II history stuff this week... the IIGS design seems interesting.
The IIgs is pretty nice, I own one.
The sound is the best of any 8 bit and the graphics are great. It should have been more than 3MHz standard but otherwise it's a great machine.
Check out the emulator link on this page:
http://www.freetoolsassociation.com/

I actually own at least 8 different Apple II type machines and their clones and the IIgs is the only one that really gets away from the limitations of the original Apple II design. I spent a lot of time on Apples when I wasn't on my Tandy CoCo. I prefer the 6809 to the 65816 but it's still a nicer cpu than the 6502.

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 9:42 am

JamesD wrote:I know just enough verilog and VHDL to follow some of the logic and I could probably write enough for this project. I want to build computers in FPGAs but it's a good idea to start small. Dealing with a handful of mistakes is a lot easier than hundreds or thousands.
That's the thing, there are lots of actual designs around, we do have schematics for all floppy controller boards (granted they are a bit complex). For things like a GS-like new board of course they are no longer valid if we increase the clock (and we should really do ;)), but if you stay at 1MHz, a stratos ext is basically fitting together existing pieces with some address decoding glue.
Using slot-based design also allows to debug and test parts separately, and redo only bad ones.
But if the parts don't exist it's a whole different thing. Getting all the old parts like the VIA and floppy controller would be a problem and the only alternative is an FPGA.
cf.
http://forum.defence-force.org/viewtopic.php?t=181
http://www.westerndesigncenter.com/ 65xx
http://www.selectronic.fr/article.asp?a ... .7268-9999 ICM 7170
http://forum.defence-force.org/viewtopic.php?t=19 for FDC (hmm their board is large...).
Not that expensive, plus a shared design allows for someone to make several boards and so order all chips, lowering shipping costs.
OTH of course an FPGA can be reprogrammed instead of redoing the board.
Not only that but there is probably some analog circuitry involved in the floppy controller and I don't know enough about analog circuits to even know where to begin.
Once again the designs exist already, plus there are reference design notes, ...
Serial port.... I'm not sure this one will even have an adjustable baud rate so it stays small to fit in the smallest (and cheapest) PLD possible. I also have source code. To be honest I figured the serial port will allow a drive to be emulated over the connection by a PC (great for the development part) or to just run a transfer utility.
You could as well reuse the k7 port...
If anything it should be at a different address just so it doesn't interfere with the stratos serial port in case someone decides to add one.
Sure.
http://passionoric.ifrance.com/fr/oric.htm seems to have most existing IO maps.

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 9:50 am

JamesD wrote:BTW, I haven't been able to find any pictures of an ORIC motherboard that doesn't have the ROMs and ULA socketed.
Didn't notice the ULA was socketed. I just saw the cpu wasn't (here goes overdrive boards), maybe that could help.
The Telestrat is too different for me to worry about but if it has the same ULA and a space for two ROMs then it would probably fit in it as well.
No ROM (cartridge), but there are plenty of
unsoldered ICs to put stuff in.
Some machines appear to have only one ROM where other ones like mine have two ROMs. However they still have the place for the 2nd ROM. Mine even has the hand labeled ROMs.
Yes, prototypes had 2*8K eproms in, and they left the layout.

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 9:52 am

JamesD wrote:I prefer the 6809 to the 65816 but it's still a nicer cpu than the 6502.
Yes 6809 has many more features, opcodes and addressing modes... it could even be used for SMP :)
We had 6809 boards at school...

mmu_man
Flying Officer
Posts: 219
Joined: Thu Sep 21, 2006 7:45 pm
Location: 26000 Valence, FRANCE
Contact:

Post by mmu_man » Sat Oct 06, 2007 4:35 pm

I just checked mine, and it doesn't have the ULA on socket.
Only the single ROM is on socket.

Post Reply