[Atari 7800 :- Controller remote pause function modification]

On 3/31/2024 at 5:08 AM, alex_79 said:

The AtariVox will work just fine (the gate input are high impedance and do not affect the levels of the pins), but the pause mod can be triggered while the Atari communicates with the device. Whether this causes issues or not depends on the specific game. The fact that current games work fine doesn't exclude the possibility that future ones might have issues.

 

The SNES2Atari adapter supported, for example, by "Attack of the PETSCII Robots" for the 7800, uses pins 1 and 2 to send the clock and latch signal to the SNES controller. The Savekey uses pins 3 and 4 for the I2C serial data and clock protocol. The "Compumate" for the 2600 uses pins 1-4 on both ports for the bankswitching of the Computer ROM.

There are some roms that use the ports to communicate with a computer serial port, or to drive external devices, and it's possible, for example, to use them to connect two consoles and play multiplayer games that way...

 

 

The 2600RGB mod uses a similar method of "impossible combination of inputs" to add an extra SWITCH on the controller to allow for remote RESET and SELECT switches, as well as an hardware PAUSE (it halts the CPU) and a PALETTE select function.

That proved to be incompatible with the mentioned trackball games (which caused disappointment to the unaware customers), but also in other cases which are less obvious:

e.g. "Track and Field" is unplayable (with a standard joystick, not only with the "Track and Field" controller that allows to press left and right simultaneously) if you have a RGB mod with the extra function wired to the controller port. And doesn't matter if you actually have the extra switch installed on the joystick.  That's because, for whatever reason, the code in the game briefly pulses pins 1-4 LOW in both ports on each frame!

 

My point is that the pins on the controller ports are general purpose Input/Output ones, and the game code has full control over them. Not only different controllers can pull up/down different combination of inputs, but the code itself can drive them directly, even when nothing is connected to the port, and the pause mod cannot tell the difference. The possibilities are infinite, and new games and controller/devices keeps being developed. That's why I suggest to have a switch to disable the function: if you ever encounter a game (or controller or device) that conflicts with it, you can just temporarily turn it off.

Alex, I tested my Avox+ and SNES2Atari adapter and didn't encounter any issues on my primary 7800. But, to be on the safe side. I did cut all the traces to the channel select switch and run new wire from the pause board and back to the RIOT to a slightly modified channel select switch to allow me to turn that pause line on/off just in case. It would be better if I could find switches just like those used originally but with longer switches so they can poke through the back of the shell better. Currently I've been reforming the pins on the bottom and using the front set of vias closest to the edge of the board to mount standard difficult/channel select switches. I did it on both my main 7800 and on an extra in the lab that I actually sold last night in a record 20min time.

Anyway, thank you again for that suggestion!

 

[Atari 7800 :- Controller remote pause function modification]

3 hours ago, alex_79 said:

The AtariVox will work just fine (the gate input are high impedance and do not affect the levels of the pins), but the pause mod can be triggered while the Atari communicates with the device. Whether this causes issues or not depends on the specific game. The fact that current games work fine doesn't exclude the possibility that future ones might have issues.

 

The SNES2Atari adapter supported, for example, by "Attack of the PETSCII Robots" for the 7800, uses pins 1 and 2 to send the clock and latch signal to the SNES controller. The Savekey uses pins 3 and 4 for the I2C serial data and clock protocol. The "Compumate" for the 2600 uses pins 1-4 on both ports for the bankswitching of the Computer ROM.

There are some roms that use the ports to communicate with a computer serial port, or to drive external devices, and it's possible, for example, to use them to connect two consoles and play multiplayer games that way...

 

 

The 2600RGB mod uses a similar method of "impossible combination of inputs" to add an extra SWITCH on the controller to allow for remote RESET and SELECT switches, as well as an hardware PAUSE (it halts the CPU) and a PALETTE select function.

That proved to be incompatible with the mentioned trackball games (which caused disappointment to the unaware customers), but also in other cases which are less obvious:

e.g. "Track and Field" is unplayable (with a standard joystick, not only with the "Track and Field" controller that allows to press left and right simultaneously) if you have a RGB mod with the extra function wired to the controller port. And doesn't matter if you actually have the extra switch installed on the joystick.  That's because, for whatever reason, the code in the game briefly pulses pins 1-4 LOW in both ports on each frame!

 

My point is that the pins on the controller ports are general purpose Input/Output ones, and the game code has full control over them. Not only different controllers can pull up/down different combination of inputs, but the code itself can drive them directly, even when nothing is connected to the port, and the pause mod cannot tell the difference. The possibilities are infinite, and new games and controller/devices keeps being developed. That's why I suggest to have a switch to disable the function: if you ever encounter a game (or controller or device) that conflicts with it, you can just temporarily turn it off.

Wow, all excellent info! Thanks! Well in my case, I believe I still have my channel select switch in place on my console and since I removed the RF from it over a year ago to add in the audio input jack, seems as good an option for making it useful again as possible? I will reform the leads on it a bit so I can try and move it further back a tiny bit to make it easier to reach.

[Atari 7800 :- Controller remote pause function modification]

8 hours ago, alex_79 said:

Nice mod and very clean job!

A couple of notes:

1- You don't need to wire the second port, but you cannot just leave the inputs of a logic gate unconnected, else they'll show erratic behavior, electrical noise and increased power consumption (especially with HC/HCT family ICs like in this case).

Simply tie "2U" and "2D" inputs on the mod board to +5V if you don't want the pause function for the second port.

 

2- Consider adding a switch to disable the mod (e.g. break the connection between the "PB" output of the board and RIOT pin 21). Else, some controllers such as driving controllers and trackballs will trigger the pause (or B&W switch in 2600 mode) function.

This can also happen when a game uses the ports as outputs: for example, pins 1 and 2 ("up" and "down" in a joystick) are used to interface with an Atarivox, and the RIOT outputs can be set simultaneously LOW by the code while trying to communicate with the device, even if nothing is plugged in the port, and that again will trigger the pause/B&W switch.

 

Given the number of different controllers and devices (and the new ones that the homebrew community keeps developing), and the great flexibility of the 2600/7800 controller ports I/O pins, there isn't a combination  that is really "impossible". There will always be some game or device that will trigger it, so you need to be able to disable it if needed.

I wasn't aware of the AtariVox functions being affected by this? I will have to give that try as one of the other many mods on my 7800 is an Audio input jack that I plug my AtariVox into to be mixed within the console and come out with the rest of the audio so I don't have to connect it to separate external speakers.

But the reason I use Up+Dn is not just because this pause kit also does, but because I originally years ago was using the Left+right combo and the Harmony cart did NOT care for it at all. I do have a diode pair inside my controllers to isolate the signals from each other independently, but the actual SMS kits only use a pair of 220ohm resistors off the inputs.

As for the driving controller and trackballs? I own them, but I never use them on my 7800 as I just don't play any games that use them.

 

[7800 oddity - a Maria that kinda? Works?]

12 hours ago, Video 61 said:

hi crossbow,

i learned very early on, that sending back a fixed unit, and then the customer plugs in a faulty power supply, controller, etc.,can avoid many headaches.

i to used my own test equipment. but i always wanted to make sure that all parts of a system, were solid.

lance

www.atarisales.com

 

Lance,

The reason I don't ask for all of their stuff is because it simply increases the shipping cost too much. Power supplies add quite a bit of weight in many cases and with shipping being what it is today, each pound adds up. I get what you are saying, but in most cases, I've done some troubleshooting with my clients ahead of time to make sure something simply like a bad PSU or controller isn't to blame first. Here is a such an example that happened last night in fact:

Had someone reach out to me through my FB profile for my ITC services. It was recommended they reach out to me to look at having their LCD replaced in their Lynx console so they wanted to know how much that would cost etc. With some questions, I asked why they wanted a new screen. And they stated because their original wasn't showing anything head on and you could only just make out the image when viewed from an extreme angle so they were looking to one of the newer screens installed etc. 

I asked them if anything changed when using the contrast wheel on the system... and they came back about 30min later stating they completely forgot that wheel was there and it was looking like it did originally again and thanked me for my time. I was happy to do that and while I could have insisted they get a new LCD still, it was only being suggested because they thought their screen wasn't working. It was and now they can play it as they wish. 

I would like to think that actions like that, will have them remember me when they might be in actual need of my services in the future so again, I try and make sure the simple stuff has been tried first for my clients before they send it all my way.

 

[7800 oddity - a Maria that kinda? Works?]

10 minutes ago, RickR said:

Fascinating.  I wonder what kind of problem in the chip would cause it to "almost" work like that? 

Nice work fixing it!

 

There is a dedicated blanking pin on the Maria. However, the odd bit is that the pin is only attached to the expansion port bus and doesn't seem to go into anything else within the video circuit. But obviously that isn't the case or there are additional signals being provided by the Maria that effected this that weren't working.

It wouldn't have surprised me if this was always an issue with this 7800 that again, just wasn't really discovered. When playing on a consumer level CRT, that extra info was likely in the overscan and just wasn't noticed.

 

[7800 oddity - a Maria that kinda? Works?]

38 minutes ago, Video 61 said:

hi crossbow,

 

 nice work. agreed on the electronics. i always demanded the power supply, t.v. switch box, and controllers to boot, if a customer wanted service. many times it turned out to be a power supply problem.

 

lance

www.atarisales.com

 

I only request the consoles to be sent in because I have spare PSUs and controllers, plus several different test carts for servicing the consoles. There has only been a few times where something arrived working 100% for me that didn't work for my clients and yes...it was indeed their power supply that was faulty in those instances, or in one case, the video cable the owner was using apparently had some loose connections in side it.

But I normally pre-test all consoles to verify the issues that are being reported or to find issues that the owner may not be aware of. An example of this would be a faulty player 2 difficulty switch or the paddle controllers not working properly for player 3 or player 4 on a 2600/7800 console. Because they might not normally use those functions, they aren't aware that they were faulty.

[RAIDERS OF THE LOST EPROMS - UPDATE!]

The IPL/Monitor label..looks exactly like the labels used on actual Parker Bros proto and WIP games. Same size lable...same looking dot matrix font printer used to print that label. 

So I'm wondering if that might not be something from PB? I know it looks a lot like my labels on my PB protos of SW:TAG WIP build and Rls1 of Gyruss that I own.

Also...IPL usually means Initial Program Load or Loader. So it could essentially be a firmware type chip for something unrelated?

 

 

[EXPERIMENTING WITH RECHARGEABLE BATTERY OPTIONS FOR SURVIVING A LONG TERM POWER OUTAGE WITH ATARI LYNX]

Few things...

Changing out the original LCD with one of the newer IPS kits apparently will extend the life of the batteries since the newer LCDs consume much less power than the original screens. Especially since the high voltage is disabled as part of those LCD upgrades.

There is a charging kit you can get to install into the Lynx II console that is specifically designed for using NiMH batteries in the lynx. Essentially the system always runs off batteries in this modification and the standard AC port now becomes the charge port. I've not done or offered this as a service due to the fact that the modification kills being able to use AC power by itself on the Lynx afterwards. But, it is an option.

One interesting thing to test would be to try finding and installing a LiON pak into the external Lynx battery pack to replace the D cells. With enough watt hours on the cell you might get quite a bit of gameplay from such a setup when combined with an LCD upgrade.

 

[Atari 5200 Thoughts]

4 minutes ago, Atari 5200 Guy said:

I don’t have Rescue on Fractalus yet.  I need to remedy that.

Yes... yes you do!

 

[Atari 5200 Thoughts]

5 minutes ago, RickR said:

And lets not forget the awesome Trakball they made for 5200.  It feels like a real arcade controller. 

Oh yeah! Missile command is pretty much arcade like with it on the 5200.

[Atari 5200 Thoughts]

The 5200 is my second favorite Atari console only bested by the 7800 for me. I've always like the original controllers since I first played the system using one of them. Over the past 20+ years now, I've done the foil dots bit on them to keep them going but after having to do it after every 2 or 3 years (due to the dots eventually falling off), I got sick of it and over the summer I purchased two gold set replacement rebuild kits from the new Atarireapairparts.com website. Installed them in a matter of minutes and I don't think I will have to touch them ever again at this point.

That said, I also have a set of the Wico controllers (I don't like this, they don't feel right and they actually break stupid easy internally.). But the command control keypad that they also use is quite nice and well built. So I also have one of the older AtariAge redemption adapters that lets me use that Wico keypad and a Sega Genesis 3 button controller with the 5200. For games that require the more digital precision, that is the setup I will use. But even still I mostly use the original controllers when I play on the 5200.

 

[To Mod or Not to Mod?]

I agree with @RickR, if you have one that is stock and this is a spare, then mod it with more games! And yes there is a limit, although it has been a few years since I did mine and I can't quite remember what that limit was. But basically you have to compromise between wanting a lot more games, or still wanting the ability to have save states on the games. 

Because what I do remember is that each of the save states were quite large (Much much larger than the actual game roms), and they were what all of the empty space was needed for. So if you fill that space with more games, then you can't have 3 or 4 save states per game anymore and in some cases if you completely fill it, you can't have any at all.

This only becomes an issue because the modded consoles OS can't really tell that the space isn't there. So if you don't have any space left and you try and use the save states, it usually ends up locking up the thing at that point. I think I settled about 30 more games being safe to add in most cases and that would still provide you with like 1 or 2 save states per game doing it that way.

Another thing you can do, is that since all of these are based on the same tech internally, you don't just have to put NES games on it. What I did was actually mod my SNES mini with both additional SNES games and some NES games that I can choose to play on it. I left my NES mini stock, but then on my Genesis mini I added some more CD games and a few 32x games if I remember along with additional genesis roms I'd want to play on it. 

 

[Weird Paddle 3 issue on a 2600 4-switch?!]

1 hour ago, alex_79 said:

I don't think it is possible. It's not only that you need to watch the CPU address and data bus to see when the program writes to the TIA register used to turn those transistors ON and OFF (not impossible, but surely complicates things a bit), as that "DUMP" signal is not available outside the TIA, but the fact that you'd need to remove the bad transistor from the circuit for this to work!

Ah.. I see. I wasn't sure if that signal was available outside of the TIA to be found elsewhere or from another pin etc. 

I wonder if the cost to need ratio just isn't there for a new TIA replacement to be produced or hardware emulated/simulated off a PCB?

 

[Weird Paddle 3 issue on a 2600 4-switch?!]

Thank you for the detailed explanation on it all Alex! But again, in this case the failed transistor is located where....? 

Inside the TIA. So I guess it is awesome to know what is failed in this case, but still stinks because it isn't something that can be fixed. Unless it were possible to just wire in an actual transistor to handle this externally on a small perf board or just wired into the system directly and then shrink wrapped up? Hmm... a bodge to allow a 95% working TIA to still be used for 100% functionality in a console. 

I'm kinda like the idea of this...

 

[A New Challenger Approaches! - A7800 BackBit Pro Adapter has arrived at the ITC!]

I know I've gone on and on about this cartridge in the past but it really is quite amazing given all the systems is can support. At this time, all of the 7800 original released titles minus Choplifter will play properly. Choplifter exhibits a timing issue through the cartridge that actually happens with actual carts on actual hardware as well. But here the BBPro seems to make it show up on all consoles vs just a few that have been encountered in the field.

Additionally, the adapter and firmware updates have also gotten quite a few more homebrews working as well. Many of Muddyvision's earlier releases work properly now without graphical glitching and with proper Pokey emulation as well. Some of the more exotic stuff using complex combos of RAM + Bankswitching+ Pokey..etc are still not working but perhaps in time those too will be possible.

 

[First Time Playing Crossbow]

10 hours ago, Atari 5200 Guy said:

I will have to find it for the 7800.  So far I love the game.  But, it's true, Crossbow I have never heard of until I started collecting video games a decade ago.

Crazy, the actual arcade cabinet was semi common when I was kid and I always drawn to it. And you know it was different because games like Operation Wolf and the later other Gun games never interested me, but anytime I saw a Crossbow cabinet I had to play and see how far I could get my friends. But like all arcade games back then, it was much more difficult than home versions and I think I was only able to get them to the ice caves before getting wiped out. Might have made it to the jungle screen, but again just way more difficult compared to the home versions.

So yeah, I was very familiar with the game and it was actually Crossbow and Xenophobe that made me want a 7800 when I was younger in the late 80s. I never was able to get Xenophobe as I don't remember being able to find it, but I remember seeing it on the Sears wish catalogs back then. But Crossbow I was able to get and I'm pretty sure I got it from Toys R Us at that time.

 

[First Time Playing Crossbow]

I might be a bit partial to this game myself...hehe. Only I play the 7800 version which, I find to be smoother game play overall.

 

[Just a simple but kinda cool project?]

I was able to do the same to a 2600jr console over the weekend. It required having to first breadboard up the wiring so I could try different value resistors before dialing it in, but finally settled on 2k being the magic number. Bu this will depend on where you tap the audio from and might still have some variation from console to console. But anything more than 2k, and the AVox gets lots in the TIA audio. It is still heard just way lower and kinda hard to make out. Less than 2K and it seems to start to kill the TIA audio instead. Anyway, here are a few pics of my 2600jr in the lab where I did this.

Here is the internal shot. You can see the wiring that runs along the back. This is to provide the audio input. The 3.5mm on the left rear of the console in this pic is the new audio input, and the original RCA for the RF and small 3.5mm next to it is my composite video output and audio out I had in place already.

 

And here is what that looks like from the rear of the console. In this pic, you see the RF output and small 3.5mm next to it that is again the audio out. The singular and slightly larger 3.5mm on the right rear side, is the audio input.

[Just a simple but kinda cool project?]

Last night I did the same thing to my daily driver 7800. As I have the RF modulator removed from that 7800 completely, I used one of my studio grade quality 3.5mm jacks for this and epoxied it to the 7800 main board in place of where the RF was since that was empty and the hole was already there in the case shell. 

 

[Just a simple but kinda cool project?]

I also just remembered that my Vectrex Audio Tap or V.A.T. for short I have installed in my Vectrex, actually has a 3.5mm jack on it for audio input for use with the Avox+ in Veccy mode! So really this has been done in this fashion several different ways in the past. I wish I had thought of this before working on all of Al's consoles last year as I'm sure this would make his PRGE setups much easier. He actually uses a separate small audio mixer for each of the consoles to mix the Avox speed with the console audio through a new audio output from the mixer box that he then plugs into his commodore monitors.

 

[Just a simple but kinda cool project?]

2 hours ago, RickR said:

Your video has an important piece of info about the AtariVox I didn't know...that it has a separate audio out.  That's kind of like the O2 "The Voice" module, except no built in speaker.  Given that thought, I wonder how well a small speaker built into a new bigger casing for the AtariVox would work?

That would work quite well provided it is loud enough and or close enough to the player to be heard clearly over the rest of the audio. Likely pretty simple to do and there might even be one of those premade project boxes that could be used for that. I've not tested this yet, but I don't see why it couldn't be done... but...

I should plug my Sony digital walkman into it LOL! I mean, I don't see a reason why it wouldn't work provided I adjust the volume?

 

[Just a simple but kinda cool project?]

15 hours ago, RickR said:

That custom 7800 case though.  👌

 

4 hours ago, - Ω - said:

Yeah, no kidding... super primo excellent.

Bob printed that case for me as a thank you for services I've provided to him a few years back. He has one he made for himself of course and also made a custom case shell for Albert for use with one of his 7800s during PRGE and other convention events.

Bob released the STLs for this case I believe yesterday for those that might want to do check it out. There are a few caveats on getting everything to fit and I don't know if his STL includes the holes already done for the RCA and s-video jacks as he did when he printed mine.

 

 

[Loctite and ABS = Gallium and Aluminum...]

3 hours ago, RickR said:

Who knew? 

Thanks for sharing.  I would have probably tried Loctite myself, so thanks for the warning.

I've been told this is likely just an issue for ABS plastics that of course all of our stuff was made back then. Apparently PLA used with 3D printing isn't affected as much? But I don't have the means to test that myself. But yeah... kinda disappointed too since I had really thought this was the fix I'd been looking for to keep the AV jacks I install nice and tight, but ehh. It isn't.

 

 

[Atari 7800 Top Favorites]

9 hours ago, Atari 5200 Guy said:

7800 got Xenophobe? Holy cow! And, yes, Food Fight of course.  I forgot to put that one on my list.  I especially love the replays when they happen. I've been playing Donkey Kong a lot since I recently scored a 7800 copy.  I'm not a huge DK fan but something about the 7800 version is just pleasing to play.  Who knows.  I don't understand it either.

Choplifter I played on the SMS first.  I never knew of the game on any Atari until maybe 10 years ago.  So when I popped the 7800 version in for the first time I was shocked how much stuff was "missing" before I learned Sega added all those extras.  I like the 7800 version better but it's tough.

Choplifter also exists on the 5200 and 8-bit line. But is uses artifacting so you really need to play if via RF or composite output to see any colors from it.

And yeah, Xenophobe is on the 7800. I think it plays better than the NES version and looks more colorful, but you only have one character to play as and it does get quite repetitive. Rampage on the 7800 is also a lot of fun and I played it a ton back in the day. But it is the definition of repetitive and so I find myself tiring of it quickly these days when I try and play it now.

 

[Atari 7800 Top Favorites]

The 7800 is my favorite Atari console but my list of games would be a bit different as I found myself more interested in the games that weren't repeats from the previous generations at the time. 

F-18: Hornet - This is not one that I play that often these days, but when I first had the system I played it all the time and once I learned exactly how the game works, similar to 2600 Adventure, I would find ways to do stuff you weren't supposed to do like flying in the other direction and stuff like that. But at the time I was pretty impressed with everything you could do in the game with the different missions.

Crossbow - shouldn't be a surprise for anyone this is on my list heh. But I've always enjoyed this game on the 7800 and prefer to play it with a controller vs light gun as it is easier to setup your cursor on the screen in known locations and just move left/right as needed to take out a good chunk of the enemies on each scene that plays out. I also thought the graphics for this game were pretty stellar back then on the 7800.

Food Fight - I had never heard or nor seen the actual arcade cabinet back in the day, but the game looked like fun when I read the box and I'm very glad I decided to pick it up back then. I play this one still from time to time as it is just so well done on the 7800.

Double Dragon - I know...kinda surprising but to me I thought this version was closer to the arcade than the NES in respect to the level designs etc. I did play the NES version as well, but always liked the 7800 version more and got to be really good at it back in the day.

Xenophobe - This is one of the games I wanted the 7800 for as the arcade cabinet was so unique in the day and I had a lot of fun playing it so when I saw it was coming for the 7800, it was pretty much the game release that made the 7800 a console I wanted in the late 80s. The irony to this is that I ended up never owning Xenophobe until much...MUCH later in life. But aside from the arcade and Lynx versions, the 7800 version is my favorite home console port of the game by far.

Galaga - was also one I picked up originally back in the day and like @Atari 5200 Guy I thought it was pretty awesome back then. Yes the NES version looks closer to the arcade but something about the 7800 version to me was just more fun to play for some reason? 

Choplifter - Is another arcade game that I had only seen in the arcade a few times and I didn't know of the releases on the 5200 and 8-bit consoles back then. So it was new to me and I played it all the time until I had method down for getting a perfect game. I still like to pop it in once in a while to see how many POWs I can save. This is another decent looking game on the 7800 as well even thought the SMS version just trounces it. (Again, I didn't know about the SMS release of the game either back then).

Joust - This was one of the few games that I already had on my 2600 and played all the time. But when I saw how much closer to the arcade look and feel the 7800 version was, I was totally on board with this one. It was also one of my mothers favorites, but oddly she still seemed to prefer to play the 2600 version more back then?

And that is my short faves list of the original released games I owned back then minus Xenophobe as mentioned before. With the home brew scene what it is on the 7800, there is just some amazing talent that has really shown just what the 7800 was able to do and with the proper resources being given, it could have done even back in the day.