827 replies to this topic

[ckrtech]

Awesome. Thanks, man. I'll probably go for a 5200 model for Monday.

As for stereo - I think that sounds like a good idea. That gives people an option for stereo if they want it, and they can just use an external adapter to downmix it to mono if they want the original.

[mimo]

yeah, go for the stereo, might as well make it a fit once install

[HARMIK]

Would that be real stereo or just mono split in two, I would not have thought the original games would have been programed that way. If mono split in two most newer TVs would do that anyway, and would help reduce a bit of complexity of the mod if its not really needed. ( Just my 2 cents )

The mod's sounds awesome I have some moded systems but it seems yours might be even better. I would love for you to do one for the Intellivision, as im sure it would be a good one

[Longhorn Engineer]

ckrtech, on Sat Jan 3, 2009 12:44 AM, said:

Awesome. Thanks, man. I'll probably go for a 5200 model for Monday.

As for stereo - I think that sounds like a good idea. That gives people an option for stereo if they want it, and they can just use an external adapter to downmix it to mono if they want the original.

5200 model is not going on preorder on Monday. Only the 2600. Sorry.

HARMIK, on Sat Jan 3, 2009 6:49 AM, said:

Would that be real stereo or just mono split in two, I would not have thought the original games would have been programed that way. If mono split in two most newer TVs would do that anyway, and would help reduce a bit of complexity of the mod if its not really needed. ( Just my 2 cents )

The mod's sounds awesome I have some moded systems but it seems yours might be even better. I would love for you to do one for the Intellivision, as im sure it would be a good one

The TIA chip has two separate channels for Audio that are mixed together so it will be "real" stereo.

[SpiceWare]

Note that Atari's in Australia are PAL and there's no stereo coming out of the PAL TIA chips. One of the audio lines was repurposed with a PAL signal.

You can see the pinouts for PAL and NTSC TIA chips here.

[Carpenter]

Hey Longhorn. Did you check the shipping costs

Edited by Carpenter, Sun Jan 4, 2009 6:24 PM.

[Longhorn Engineer]

Carpenter, on Sun Jan 4, 2009 6:23 PM, said:

Hey Longhorn. Did you check the shipping costs

I will find out tomorrow.

[Longhorn Engineer]

Finally! I am opening up preorders for the 2600 Version 2.2B of the mod.

2600 Schematic Picture V2.2B
2600 Schematic File V2.2B
2600 PCB File V2.2B
2600 Part List V2.2B

Fully Assembled Mod Kits will be $40 + $10 shipping.
Blank PCBs will be $6 shipped.
Atari Modding service will be $100 + $15 return shipping.
Schematic and PCB design FREE!!!

Market Place thread here.

To preorder send me and Email using this form. In the title put something obvious like "Want to preorder 2600 Kit" or something. In the email tell me your name and what service you want. If you are outside the Continental USA please state so. Once I get a decent number of orders probably (20 or so kits) I will close preorders and send invoices to everyone that ordered. Payment will be by paypal. Turn around will be a month or less after preorders close. People who chose to ship there Ataris for modding should expect a bit longer. Please do not send an email if are not going to pay when invoices are going to be sent out.

Edited by Longhorn Engineer, Mon Jan 5, 2009 4:33 PM.

[Carpenter]

Great! What software should I use to open the schematic and board files? Is the board single or double face?

[Longhorn Engineer]

ExpressPCB

Its free and the PCB is double sided.

Edited by Longhorn Engineer, Tue Jan 6, 2009 4:27 PM.

[hex65000]

Your mod looks great, I do have some questions about the fms6400 though...

The datasheet says you need to tie Asel high or low, and in your schematic it looks like you have it floating. Is that on purpose, or am I missing something?

I'm not up on doing impedance matching so this question relates to the application note in the datasheet. In it they show an optional AC coupling of the output signals. I would think that would be somewhat more desirable than DC coupling the outputs or does it not really matter and omitting the 220uF caps is more of an easy way to keep the part count down?

I haven't poked at your PCB file yet, but from the photo you posted, you might want to consider going surface mount for your next rev/update. You can probably shrink the board a bit more which would make it a more intermediate project. I'd suggest an SOIC package for your CD4050 (provided that they are available) and either 1206 or 2010 form factor resistors. If you want to get daring, you can swap out your caps that are 1uF or smaller for 0805 package caps. I know you can get electrolytic SMT parts, but honestly I think they are more work than they are worth to get on a board. I personally wouldn't bother with an SMD 2n3904 / 1n914 either.

A little late perhaps -- my 0.02 cents...

Hex.
[ Is intrigued by this and yet doesn't have time to do all those other things I need to get done... ]

[Longhorn Engineer]

hex65000, on Wed Jan 7, 2009 4:29 PM, said:

Your mod looks great, I do have some questions about the fms6400 though...

The datasheet says you need to tie Asel high or low, and in your schematic it looks like you have it floating. Is that on purpose, or am I missing something?

I'm not up on doing impedance matching so this question relates to the application note in the datasheet. In it they show an optional AC coupling of the output signals. I would think that would be somewhat more desirable than DC coupling the outputs or does it not really matter and omitting the 220uF caps is more of an easy way to keep the part count down?

I haven't poked at your PCB file yet, but from the photo you posted, you might want to consider going surface mount for your next rev/update. You can probably shrink the board a bit more which would make it a more intermediate project. I'd suggest an SOIC package for your CD4050 (provided that they are available) and either 1206 or 2010 form factor resistors. If you want to get daring, you can swap out your caps that are 1uF or smaller for 0805 package caps. I know you can get electrolytic SMT parts, but honestly I think they are more work than they are worth to get on a board. I personally wouldn't bother with an SMD 2n3904 / 1n914 either.

A little late perhaps -- my 0.02 cents...

Hex.
[ Is intrigued by this and yet doesn't have time to do all those other things I need to get done... ]

Good questions. The chip defaults to high when the output is not connected to ground. It operates fine with it disconnected and I haven't seem any adverse affects from all the TVs and hours I have tested the board.

The chip can be both AC or DC coupled outputs. It has to have AC coupled inputs. From what I have seen having AC coupling does nothing in terms of video quality. 220uF caps are fairly large in size and took up 25% of the space on the board before removing them.

The big reason to stay with through hole is the Unassembled Kits and Bare PCBs. Plus I really dislike soldering SMD parts.

Edited by Longhorn Engineer, Wed Jan 7, 2009 4:42 PM.

[ckrtech]

Longhorn Engineer, on Wed Jan 7, 2009 4:41 PM, said:

Plus I really dislike soldering SMD parts.

Seconded!

In fact, it is preventing me from reflowing the 8bitdomain board I have right now. I just look at it and am like...I should just try to return this and say the S-Video doesn't work and pickup the Longhorn mod.

But I still liked reading hex65000's ideas for your next revision. Small is awesome so long as you don't have to do the soldering yourself.

Edited by ckrtech, Wed Jan 7, 2009 4:58 PM.

[Carpenter]

Some thoughts

I was checking the design and did notice that the audio caps (1uF) are pointed in schematics as being electolytic and the board contains ceramic footprints. Which one is correct? Maybe the board should include ground planes on both faces once they add no cost to production and can help system's electromagnetic interference performance. Last, but not the least, the output ground conections should be grouped with its respectively signals (right and left audio, chroma/luminance or composite) thus allowing easy cable conections.

Just my 1/2 cents too. Good job

Edited by Carpenter, Wed Jan 7, 2009 6:02 PM.

[Longhorn Engineer]

Carpenter, on Wed Jan 7, 2009 6:00 PM, said:

Some thoughts

I was checking the design and did notice that the audio caps (1uF) are pointed in schematics as being electolytic and the board contains ceramic footprints. Which one is correct? Maybe the board should include ground planes on both faces once they add no cost to production and can help system's electromagnetic interference performance. Last, but not the least, the output ground conections should be grouped with its respectively signals (right and left audio, chroma/luminance or composite) thus allowing easy cable conections.

Just my 1/2 cents too. Good job

Thanks for pointing that out. I will add a "+" sign to make assembly easier on the end user. I guess I can add ground planes. My prototypes have no such and they perform quite well. Could easily add that to. I can move the ground connections to.

[Frotz]

Longhorn Engineer, on Wed Jan 7, 2009 2:41 PM, said:

hex65000, on Wed Jan 7, 2009 4:29 PM, said:

Your mod looks great, I do have some questions about the fms6400 though...

The datasheet says you need to tie Asel high or low, and in your schematic it looks like you have it floating. Is that on purpose, or am I missing something?

I'm not up on doing impedance matching so this question relates to the application note in the datasheet. In it they show an optional AC coupling of the output signals. I would think that would be somewhat more desirable than DC coupling the outputs or does it not really matter and omitting the 220uF caps is more of an easy way to keep the part count down?

I haven't poked at your PCB file yet, but from the photo you posted, you might want to consider going surface mount for your next rev/update. You can probably shrink the board a bit more which would make it a more intermediate project. I'd suggest an SOIC package for your CD4050 (provided that they are available) and either 1206 or 2010 form factor resistors. If you want to get daring, you can swap out your caps that are 1uF or smaller for 0805 package caps. I know you can get electrolytic SMT parts, but honestly I think they are more work than they are worth to get on a board. I personally wouldn't bother with an SMD 2n3904 / 1n914 either.

A little late perhaps -- my 0.02 cents...

Hex.
[ Is intrigued by this and yet doesn't have time to do all those other things I need to get done... ]

Good questions. The chip defaults to high when the output is not connected to ground. It operates fine with it disconnected and I haven't seem any adverse affects from all the TVs and hours I have tested the board.

The chip can be both AC or DC coupled outputs. It has to have AC coupled inputs. From what I have seen having AC coupling does nothing in terms of video quality. 220uF caps are fairly large in size and took up 25% of the space on the board before removing them.

The big reason to stay with through hole is the Unassembled Kits and Bare PCBs. Plus I really dislike soldering SMD parts.

If it's not too late, do you think you could tie that wire high for completeness and just in case it turns out that something starts oscillating that shouldn't?

[Longhorn Engineer]

Frotz, on Sat Jan 10, 2009 9:55 PM, said:

Longhorn Engineer, on Wed Jan 7, 2009 2:41 PM, said:

hex65000, on Wed Jan 7, 2009 4:29 PM, said:

Your mod looks great, I do have some questions about the fms6400 though...

The datasheet says you need to tie Asel high or low, and in your schematic it looks like you have it floating. Is that on purpose, or am I missing something?

I'm not up on doing impedance matching so this question relates to the application note in the datasheet. In it they show an optional AC coupling of the output signals. I would think that would be somewhat more desirable than DC coupling the outputs or does it not really matter and omitting the 220uF caps is more of an easy way to keep the part count down?

I haven't poked at your PCB file yet, but from the photo you posted, you might want to consider going surface mount for your next rev/update. You can probably shrink the board a bit more which would make it a more intermediate project. I'd suggest an SOIC package for your CD4050 (provided that they are available) and either 1206 or 2010 form factor resistors. If you want to get daring, you can swap out your caps that are 1uF or smaller for 0805 package caps. I know you can get electrolytic SMT parts, but honestly I think they are more work than they are worth to get on a board. I personally wouldn't bother with an SMD 2n3904 / 1n914 either.

A little late perhaps -- my 0.02 cents...

Hex.
[ Is intrigued by this and yet doesn't have time to do all those other things I need to get done... ]

Good questions. The chip defaults to high when the output is not connected to ground. It operates fine with it disconnected and I haven't seem any adverse affects from all the TVs and hours I have tested the board.

The chip can be both AC or DC coupled outputs. It has to have AC coupled inputs. From what I have seen having AC coupling does nothing in terms of video quality. 220uF caps are fairly large in size and took up 25% of the space on the board before removing them.

The big reason to stay with through hole is the Unassembled Kits and Bare PCBs. Plus I really dislike soldering SMD parts.

If it's not too late, do you think you could tie that wire high for completeness and just in case it turns out that something starts oscillating that shouldn't?

Done.


V2.2C - This is the Final version that will be sent off to the PCB fab unless I find something wrong with it.
Schematic Image
Schematic File
PCB File

[ckrtech]

Longhorn Engineer, on Sat Jan 10, 2009 10:21 PM, said:

Done.


V2.2C - This is the Final version that will be sent off to the PCB fab unless I find something wrong with it.

Don't forget to change the revision number on the PCB.

[Longhorn Engineer]

ckrtech, on Sun Jan 11, 2009 1:19 AM, said:

Longhorn Engineer, on Sat Jan 10, 2009 10:21 PM, said:

Done.


V2.2C - This is the Final version that will be sent off to the PCB fab unless I find something wrong with it.

Don't forget to change the revision number on the PCB.

Fixed

[Ikrananka]

Wow - the screen shots from your mod are incredible - is that to a HD LCD/plasma TV?

Now, if you could produce the same for the ColecoVision I'd be a very happy man

[Thorsten Günther]

SpiceWare, on Sat Jan 3, 2009 11:18 PM, said:

Note that Atari's in Australia are PAL and there's no stereo coming out of the PAL TIA chips. One of the audio lines was repurposed with a PAL signal.

You can see the pinouts for PAL and NTSC TIA chips here.

And additionally, the PAL TIA has no BLK signal (PIN 6 on NTSC TIA) - so I don't know whether this mod really has less vertical lines than the CD4050 mod in the FAQ on PAL machines or does work at all (the other signals are just on some other pins).


Thorsten

[Longhorn Engineer]

Thorsten Günther, on Tue Jan 13, 2009 1:35 PM, said:

SpiceWare, on Sat Jan 3, 2009 11:18 PM, said:

Note that Atari's in Australia are PAL and there's no stereo coming out of the PAL TIA chips. One of the audio lines was repurposed with a PAL signal.

You can see the pinouts for PAL and NTSC TIA chips here.

And additionally, the PAL TIA has no BLK signal (PIN 6 on NTSC TIA) - so I don't know whether this mod really has less vertical lines than the CD4050 mod in the FAQ on PAL machines or does work at all (the other signals are just on some other pins).


Thorsten

Yes hopefully when mimo gets the mods and tests them we can figure out whats going on

Once the preorders get shipped I will be opening up normal orders for the 2600 mod. At the moment the time frame for the 7800 version is 1 month. Maybe less.

[Longhorn Engineer]

Been kicking the 7800 version of the mod around. Seems the biggest issue is separating the 7800 and 2600 chroma lines from each other. The Luma lines go through a NOR gate (U3). I am assuming the NOR gate separates the 7800 and 2600 lines.

When the 7800 mode is on what is being sent by the TIA? 0 or 1?
When the 2600 mode is on what is being sent by the MARIA? 0 or 1?

If it is a NOR gate then the "inactive" mode has to be set to low to even get a difference in the output but it is inverted. I guess I can head to the EE lab on Friday (have those off!) and figure it out if no one knows.

Then I have to figure out how to detect when the board is in 7800 mode. There has to be a signal somewhere that is high when 7800 mode is enabled and low when 2600 (or vise versa?). If I can figure this out then it will be pretty easy to let the Mod know when to switch to 2600/7800 chroma line.

Anyone with more knowledge of the inner secrets of the 7800 would like to share?

edit// I guess one way for the mod to know is to figure out how to read when the 7800 kicks the bios screen into gear.

Edited by Longhorn Engineer, Tue Feb 3, 2009 9:53 PM.

[Frotz]

Longhorn Engineer, on Tue Feb 3, 2009 7:21 PM, said:

Anyone with more knowledge of the inner secrets of the 7800 would like to share?

edit// I guess one way for the mod to know is to figure out how to read when the 7800 kicks the bios screen into gear.

I'd start looking at the little cartridge connectors to the sides of the main one. I'd wager that at least one of those is pulled high or low when a 7800 cart is inserted. Look at 7800 cart guts.

[Longhorn Engineer]

Frotz, on Wed Feb 4, 2009 12:54 AM, said:

Longhorn Engineer, on Tue Feb 3, 2009 7:21 PM, said:

Anyone with more knowledge of the inner secrets of the 7800 would like to share?

edit// I guess one way for the mod to know is to figure out how to read when the 7800 kicks the bios screen into gear.

I'd start looking at the little cartridge connectors to the sides of the main one. I'd wager that at least one of those is pulled high or low when a 7800 cart is inserted. Look at 7800 cart guts.

Maybe, from what I found out is that the 7800's bios checks the cart for the encryption key. If it doesn't find it then it defaults into 2600 mode. I figure it would be easier to attach the kit to the bios chip then the cart slot.