16 replies to this topic

[chriswhit]

I am getting ready to build a development system with one of my 7800's. I am wondering if there are any advantages or disadvantages with using one style 7800 over another?

[GroovyBee]

Are you using Eckhard Stolberg's site as a reference?

http://home.arcor.de...ools/index.html

With the parallel port cable and homebrew RAM cart you can upload games using the 7800's joystick port.

Eckhard was working on a USB version of the cable but I don't know how far along that project is.

[chriswhit]

GroovyBee, on Fri Nov 20, 2009 8:35 AM, said:

Are you using Eckhard Stolberg's site as a reference?

http://home.arcor.de...ools/index.html

With the parallel port cable and homebrew RAM cart you can upload games using the 7800's joystick port.

Eckhard was working on a USB version of the cable but I don't know how far along that project is.

Yes that is the site I'm using for reference. A usb cable would be nice. I was going to get an older computer with a parallel port but if I could use usb it would be better. Maybe I could get pinout info for the usb and parallel port and craft my own. I'm guessing that I would need drivers though but I have some crafty friends when it comes to software.

[GroovyBee]

chriswhit, on Fri Nov 20, 2009 8:49 AM, said:

Yes that is the site I'm using for reference. A usb cable would be nice. I was going to get an older computer with a parallel port but if I could use usb it would be better. Maybe I could get pinout info for the usb and parallel port and craft my own. I'm guessing that I would need drivers though but I have some crafty friends when it comes to software.

I think Eckhard was working on a serial USB interface from the PC to the joystick port. You'd need the cable and a serial version of the 7800 dev OS firmware. Neither items have have been released as far as I know.

EDIT: For clarity.

Edited by GroovyBee, Fri Nov 20, 2009 9:01 AM.

[mimo]

as far as modding the console, a PAL system is easiest as you just drop in the new eprom, but I guess that if you can build the dev cart then a few wires for modding an NTSC console will be any problem

[gdement]

mimo, on Fri Nov 20, 2009 11:30 AM, said:

as far as modding the console, a PAL system is easiest as you just drop in the new eprom, but I guess that if you can build the dev cart then a few wires for modding an NTSC console will be any problem

This reminds me of something I was wondering about.
PAL 7800's have a socketed Maria, don't they? And they have a socketed boot ROM.
So suppose you were to plug in an NTSC Maria in a PAL console. Would that make it usable with NTSC?
They sell Maria chips at Best Electronics.
Depending how much needs to be done with the supporting video circuitry, then I wonder if it might be easier than modding a socket-less NTSC console.

[Mitch]

gdement, on Mon Nov 23, 2009 7:50 PM, said:

This reminds me of something I was wondering about.
PAL 7800's have a socketed Maria, don't they? And they have a socketed boot ROM.
So suppose you were to plug in an NTSC Maria in a PAL console. Would that make it usable with NTSC?
They sell Maria chips at Best Electronics.
Depending how much needs to be done with the supporting video circuitry, then I wonder if it might be easier than modding a socket-less NTSC console.

It's more complicated than that.

Mitch

[chriswhit]

GroovyBee, on Fri Nov 20, 2009 9:01 AM, said:

chriswhit, on Fri Nov 20, 2009 8:49 AM, said:

Yes that is the site I'm using for reference. A usb cable would be nice. I was going to get an older computer with a parallel port but if I could use usb it would be better. Maybe I could get pinout info for the usb and parallel port and craft my own. I'm guessing that I would need drivers though but I have some crafty friends when it comes to software.

I think Eckhard was working on a serial USB interface from the PC to the joystick port. You'd need the cable and a serial version of the 7800 dev OS firmware. Neither items have have been released as far as I know.

EDIT: For clarity.

I think I found a way to use it through usb. I built the cable by the directions using a controller wire and a parallel port cable then I found this on Ebay. http://cgi.ebay.com/...e=STRK:MEWNX:IT I don't know if it will work yet as it hasn't showed up yet. I don't have a parallel port in my computer.

[GroovyBee]

chriswhit, on Tue Nov 24, 2009 7:03 AM, said:

I don't know if it will work yet as it hasn't showed up yet. I don't have a parallel port in my computer.

I suspect that its not going to work. The PC downloading software will probably be accessing the parallel port's hardware registers directly. Therefore it won't know anything about a USB to parallel printer interface.

[jaybird3rd]

The "parallel-to-USB"/"USB-to-parallel" adapters that I've seen are not true parallel ports; they are recognized by the OS as a "USB Printer Port," and contain only the functionality needed to allow you to connect a printer using an old parallel cable.

If you have a desktop computer, install a PCI parallel port card ($15 or less), and for the time being, use a DOS emulator that supports parallel port redirection for the 7800CTRL program. I can't say I've ever tried 7800CTRL inside an emulator (I built a real DOS box for this sort of thing), but theoretically it should work. If you have a laptop, get a PC Card parallel port card instead.

I'm working (on and off) on a Java implementation of 7800CTRL that will allow parallel port transfers to/from the 7800 without having to rely on DOS. When completed, it should work on any platform that supports the RXTX API (MAC OS X, Windows, Linux/FreeBSD, etc).

Edited by jaybird3rd, Tue Nov 24, 2009 9:36 AM.

[chriswhit]

Thanks for all your info so far guys. I have decided to use a 7800 with the expansion as I have two of them now. I have a few question though. One of my 7800's has a color issue that is more noticeable in 2600 mode and the sky on Pole position 2 for 7800 has a bit of purple tint will this affect the operation of the dev mod? If so is there a way to adjust it without any color bar generator or diagnostics cart? If I need a tool where can I get one? Thank you

[chriswhit]

I finally got all my parts in the mail for my dev system. My console mod is finnished with the devos. I burned the 2764 myself with my Willem advanced eprom burner. I put both operating systems on it. Sweet. The cable is done to. Now I just have to finnish the ram cart. I'm still waiting for my sram chip in the mail. I can't wait. The system still plays games great for those of you who are wondering. I guess I didn't need to buy a spare 7800 after all but it never hurts to have a spare. Thanks for the help guys

[shadow460]

That's the cool thing about DevOS. It doesn't affect the day to day operation of the 7800. Mine runs the just DevOS BIOS. I was asked if I wanted a dual boot BIOS, but I declined. It takes a second longer to hit select then reset.

I was gonna recommend an earlier system for the mod. Mine is one of the later ones, and it took me a while to socket the BIOS and MARIA chips. You don't have to pull the MARIA. I only did because at the time I was planning another mod which I never completed.

[chriswhit]

shadow460, on Sat Dec 5, 2009 12:10 AM, said:

That's the cool thing about DevOS. It doesn't affect the day to day operation of the 7800. Mine runs the just DevOS BIOS. I was asked if I wanted a dual boot BIOS, but I declined. It takes a second longer to hit select then reset.

I was gonna recommend an earlier system for the mod. Mine is one of the later ones, and it took me a while to socket the BIOS and MARIA chips. You don't have to pull the MARIA. I only did because at the time I was planning another mod which I never completed.

I used an 84 which was already socketed. I'm assuming that you are talking about the xboard? I'm thinking about this to. I don't know much about it but I'm assuming that it's needed for certain games when using a ram cart but I'm not sure. I'm going to read up on that today. Surprisingly the dev. mod was very easy once I got into it. I made a mistake building my ram cart out of a Hat trick cart. I didn't take note of which way the to chips were turned on the board lol. Can anyone tell me which way they go or post a pic of the inside of a stock cart. Thank you everyone. Also there is a typo error in the directions for the console mod for anyone building one of these. pin 14 on the 74LS04 is also sodered to the 74ls08.

Edited by chriswhit, Sat Dec 5, 2009 9:03 AM.

[jaybird3rd]

chriswhit, on Sat Dec 5, 2009 8:42 AM, said:

I used an 84 which was already socketed. I'm assuming that you are talking about the xboard? I'm thinking about this to. I don't know much about it but I'm assuming that it's needed for certain games when using a ram cart but I'm not sure. I'm going to read up on that today. Surprisingly the dev. mod was very easy once I got into it. I made a mistake building my ram cart out of a Hat trick cart. I didn't take note of which way the to chips were turned on the board lol. Can anyone tell me which way they go or post a pic of the inside of a stock cart. Thank you everyone. Also there is a typo error in the directions for the console mod for anyone building one of these. pin 14 on the 74LS04 is also sodered to the 74ls08.

As I recall, the pin orientation is silkscreened onto the cartridge PCB, but in case it isn't, Pin 1 is usually on the right-hand side (when looking at the component side of the board, with the fingers on the bottom).

[primeform]

I just bought an extra 7800 that I would like to turn into a dev machine. I have no electronic skills and was wondering if any of you, that have done this mod already, would be interested in doing mine for a fee? drop me a message if your into this!

[jaybird3rd]

primeform, on Wed Feb 24, 2010 3:45 AM, said:

I just bought an extra 7800 that I would like to turn into a dev machine. I have no electronic skills and was wondering if any of you, that have done this mod already, would be interested in doing mine for a fee? drop me a message if your into this!

I can help you with this. PM sent!