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This probably isn't the right thread for this but what are the chances a Sega Sports Pad could be modded to export gray code?

I can't find a schematic for it so I'm just guessing, but there's a fair chance that the trackball uses quadrature encoding at the first stage. If so, then there's probably some sort of buffer/amplifier conditioning those signals before they're processed further, unless maybe they feed directly into a microcontroller in which case you'd need to add a digital buffer or analog op amp to boost the signal from the optical sensors up to a nice +5v/0v signal.

 

If you happen to know of a schematic, I can take a better guess. If I happen to run across one at a thrift store, I'll probably buy just because I'm in a trackball groove. :)

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I can't find a schematic for it so I'm just guessing, but there's a fair chance that the trackball uses quadrature encoding at the first stage. If so, then there's probably some sort of buffer/amplifier conditioning those signals before they're processed further, unless maybe they feed directly into a microcontroller in which case you'd need to add a digital buffer or analog op amp to boost the signal from the optical sensors up to a nice +5v/0v signal.

 

If you happen to know of a schematic, I can take a better guess. If I happen to run across one at a thrift store, I'll probably buy just because I'm in a trackball groove. :)

 

You can use it with the Genesis on EA's Marble Madness port as well as the Japanese Tengen version. Maybe that'll sweeten up that proposition. Unfortunately, Atari's Missile Command port to the Genesis does not support it.

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You can use it with the Genesis on EA's Marble Madness port as well as the Japanese Tengen version. Maybe that'll sweeten up that proposition. Unfortunately, Atari's Missile Command port to the Genesis does not support it.

I just made a steal on Amazon for a Sega Sports Pad. I plan on modding it. But before I do, any other SMS or Genesis/MD games that work with this (besides the three crappy sports titles)? :P

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My CX-80 thinks it is a CX-22. UP or LEFT indicates direction of travel and DOWN or RIGHT alternates with each pulse. Vertical movement on the trackball is on the horizontal joystick axis and visa versa.

 

I am attempting to navigate the Harmony menu with the switch in JS position. TESTCART.BIN indicates I am getting normal joystick behavior with the switch in JS position so the mode select switch is functioning properly (rolling the trackball north, south, east, or west pushes the joystick in the proper direction), but Harmony menu itself still acts screwy, even with the trackball in JS mode.

I finally dug out my JS mode trackball. I also had trouble with navigation of the Harmony menu. But, I know exactly what my "problem" is.

 

It's all but impossible to roll the ball up or down without getting a litttle left/right activity in the process. The Left/Right directions are used by Harmony to move up/down full pages at a time. Maybe this could account for the wonky behavior you're seeing, too.

 

 

 

On the plus side, I did figure out how to use this trackball attribute in my favor when navigating with my ST mouse compatible trackball. With the driving controller, moving just one state change is easy. But when attempting to roll the TB, it's really tough to move just one click so I often jump through a bunch of items at once. But, if I roll the ball mostly up or down with just a slight left or right angle, control becomes pretty stable. Harmony don't know nuthin' 'bout no trackball signals on the vertical axis.

Edited by BigO
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I finally dug out my JS mode trackball. I also had trouble with navigation of the Harmony menu. But, I know exactly what my "problem" is.

 

It's all but impossible to roll the ball up or down without getting a litttle left/right activity in the process. The Left/Right directions are used by Harmony to move up/down full pages at a time. Maybe this could account for the wonky behavior you're seeing, too.

I was thinking this same thing when other people were talking about navigating the menu. Not too sure if it is the only problem, but yeah it would be really tough to stay completely on-axis.

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You can use it with the Genesis on EA's Marble Madness port as well as the Japanese Tengen version. Maybe that'll sweeten up that proposition. Unfortunately, Atari's Missile Command port to the Genesis does not support it.

I cleaned out my Sega Sports Pad tonight and tested it on my Everdrive with Japanese and US ROMs for Marble Madness. I even tried the SMS version. I cannot get either game to respond except in JS mode. The Everdrive MD I select the ROM using the gamepad, then swap over to the Sega trackball after the ROM loads. I cannot either game to respond properly. Navigating menus is also a PITA in JS mode, impossible in TB mode.

 

This probably isn't the right thread for this but what are the chances a Sega Sports Pad could be modded to export gray code?

I opened mine up tonight. The schematic is very clean compared to the Atari CX-80. There are only three IC chips present. Two 7402 quad NOR gates and a third IC I have not identified, likely some sort of microcontroller or custom ASIC. The encoder wheels are connected by ribbons to special headers on the main IC. There's also plenty of room to add a female 9-pin plug to the case in order to export ST Mouse gray code.

 

Also the Sega pad uses a 2.25" ball which look really cool replaced by a yellow 1-ball or 9-ball.

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I cleaned out my Sega Sports Pad tonight and tested it on my Everdrive with Japanese and US ROMs for Marble Madness. I even tried the SMS version. I cannot get either game to respond except in JS mode. The Everdrive MD I select the ROM using the gamepad, then swap over to the Sega trackball after the ROM loads. I cannot either game to respond properly. Navigating menus is also a PITA in JS mode, impossible in TB mode.

 

 

Can you navigate the Everdrive with a Sega Game Pad connected to controller port 2?

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Can you describe that a bit more detailed?

I didn't have time to play it for too long. I had just finished playing Millipede, where I could really zip around quite fast. When I tried Colony 7 it always felt like I was stopping short of how far I expected to travel, and I would have to use 2 strokes of the ball to get to a place I felt I should get to in 1.

 

 

I took a brief look and I believe the problem is the scanline range for samples. It looks like Colony 7 uses a 130 line range to read samples. Millipede uses 170, and SW Arcade uses 176. If you can get some samples while drawing the bottom of the screen I think that would really help.

 

 

I'm don't know the range in Reactor, but it feels fine. You can only travel in short spaces in Reactor so I imagine you can use a small range.

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Can you navigate the Everdrive with a Sega Game Pad connected to controller port 2?

Am I supposed to plug the trackball into port 2? They both appear to support 2 player alternating so I thought the p2 port was only used for player 2. I have no access to a manual for either game. :dunce:

 

Sounds silly but all the SMS and 7800 lightgun games used port 1. I remember briefly thinking my phasor didn't work because I initially tried port 2. In fact Nintendo is the only company I know of that consistently uses port 2 for accessory controllers,

 

Okay, I just read the manual for the EA port in the US. There is no mention anywhere of Sega Sports Pad or Genesis mouse. I suppose the people who used it in Marble madness only kept it in Dpad mode. I'm calling this a bust.

http://segaretro.org/File:Marblemadness_md_us_manual.pdf

 

Anybody got a scan of the Tengen manual? I don't even care if it's in Japanese. Food for though, the Tengen version definitely has better sound and gameplay.

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Colony 7 felt a little sluggish.

I'm thinking that the hardware I've hacked up may be mechanically different enough that it's putting out more pulses per ball rotation than the stock stuff. I like the way it plays, but I may need to refrain from offering play testing feedback.

 

Did it seem playable for you? On my hardware, I also had to flick the ball or make two moves to get across the screen in a hurry in CX-22 mode, whereas in STMouse mode it was much more fingertip control. But, it was quite in either mode.

 

I've been able to make it to squad 7 with STM (quadrature) mode, to squad 6 with CX22 (dir+clock) mode. Has anyone played enough of the joystick version to offer a comparison? I may have to do that soon.

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Are you playing normal speed or doubled speed?

I'm playing on A difficulty, doubled speed.

As best I recall, the trackball response was consistent on either speed. I haven't played much of the normal speed.

 

Is normal (B difficulty) the same as the original joystick version I played some of the original version today. I only got to squad 3.

 

(I am by no means particularly skillful at playing video games, except maybe Circus Atari)

Edited by BigO
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Am I supposed to plug the trackball into port 2? They both appear to support 2 player alternating so I thought the p2 port was only used for player 2. I have no access to a manual for either game. :dunce:

 

Sounds silly but all the SMS and 7800 lightgun games used port 1. I remember briefly thinking my phasor didn't work because I initially tried port 2. In fact Nintendo is the only company I know of that consistently uses port 2 for accessory controllers,

 

Okay, I just read the manual for the EA port in the US. There is no mention anywhere of Sega Sports Pad or Genesis mouse. I suppose the people who used it in Marble madness only kept it in Dpad mode. I'm calling this a bust.

http://segaretro.org/File:Marblemadness_md_us_manual.pdf

 

Anybody got a scan of the Tengen manual? I don't even care if it's in Japanese. Food for though, the Tengen version definitely has better sound and gameplay.

 

I don't think it's a bust yet because too many people online have said it works. I'm thinking Krizz didn't build in Sega SMS Sports Pad or Sega Mouse support for driving the menus for his EverDrives.

 

Of course, this is all independent of any goal to mod a Sega Sports Pad into exporting gray code. I think the only other classic gaming trackball - or pseudo trackball - left to potentially mod into exporting gray code would be the Coleco Roller Controller. Maybe that would be of value to the Coleco homebrew scene. Or maybe someone on the Atari side would actually like to use one of those with their Atari consoles just for the hell of it.

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I don't think it's a bust yet because too many people online have said it works. I'm thinking Krizz didn't build in Sega SMS Sports Pad or Sega Mouse support for driving the menus for his EverDrives.

 

Of course, this is all independent of any goal to mod a Sega Sports Pad into exporting gray code. I think the only other classic gaming trackball - or pseudo trackball - left to potentially mod into exporting gray code would be the Coleco Roller Controller. Maybe that would be of value to the Coleco homebrew scene. Or maybe someone on the Atari side would actually like to use one of those with their Atari consoles just for the hell of it.

Well the menu goes berserk with the Sega trackball plugged in with Sports mode. I have considered that the ROM may be detecting the sports pad on boot and have countered this by hitting reset on the Genesis. This boots back to the Everdrive menu, however the previously flashed game can be booted immediately by hitting Start. Now navigating the Everdrive menu does not work very well since the Genesis is expecting at least a 3-button controller. SMS pads respond as if they are simultaneously pressing two buttons. B and C are the default buttons when the Select line is high. A and Start are the default buttons when the select line is low. The Genesis is rapidly cycling the Select output expecting to read signals from different buttons on the Genesis pad. All this while the trackball is constantly sending spastic inputs to the Dpad. The right button on the trackball can get the previous game to load if I hit it repeatedly so any detection schemes the game does on boot would work.

 

I made it to stage 3 in Marble Madness using Joystick mode, but this is just makes you think you're playing with a real trackball. Converting analog to discrete digital is a placebo since you think you're creating analog trackball movement when it's really not. You still need to press a button to get turbo speed. Digital input from an analog device is imprecise and sloppy, which is also why I don't use the analog sticks on modern controllers to play digital games. In Sports mode, the ball won't move at all or behaves chaotically. From what I've read, the Sega Sports pad trackball sends data serially to the Genesis/SMS rather than parallel like the ST Mouse. The console is capable of pulling the normally high pins on the controller port to low, thus sending signals out. The Genesis uses the unconnected SMS pin 7 to strobe controllers for extra buttons. But all nine pins are connected on the Sega trackball. I assume the SMS uses a clock/latch system similar to NES controller polling to fetch the plus or minus delta value of the trackball positions. This allows of course multiple clocks per poll without losing bits of information.

 

I am tempted to just gut the PCB or pull the gray code directly off of the 7402 quad NOR chip if I can't get it to work natively with either version Marble Madness for Genesis, MD, or SMS (I could give dick about the three SMS sports titles that used it), but it appears the encoder wheels have lower precision on it. Apparently it has 16 or 18 instead of 24 teeth. I'm not sure if this would make the controller sluggish or not compared to the Atari trackballs as I have no way to accurately measure the roller diameter. If the roller is indeed smaller then they may have similar resolution. Ball is a standard 2.25 inch mottled yellow pool cue, same size as Atari.

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Well the menu goes berserk with the Sega trackball plugged in with Sports mode. I have considered that the ROM may be detecting the sports pad on boot and have countered this by hitting reset on the Genesis. This boots back to the Everdrive menu, however the previously flashed game can be booted immediately by hitting Start. Now navigating the Everdrive menu does not work very well since the Genesis is expecting at least a 3-button controller. SMS pads respond as if they are simultaneously pressing two buttons. B and C are the default buttons when the Select line is high. A and Start are the default buttons when the select line is low. The Genesis is rapidly cycling the Select output expecting to read signals from different buttons on the Genesis pad. All this while the trackball is constantly sending spastic inputs to the Dpad. The right button on the trackball can get the previous game to load if I hit it repeatedly so any detection schemes the game does on boot would work.

 

I made it to stage 3 in Marble Madness using Joystick mode, but this is just makes you think you're playing with a real trackball. Converting analog to discrete digital is a placebo since you think you're creating analog trackball movement when it's really not. You still need to press a button to get turbo speed. Digital input from an analog device is imprecise and sloppy, which is also why I don't use the analog sticks on modern controllers to play digital games. In Sports mode, the ball won't move at all or behaves chaotically. From what I've read, the Sega Sports pad trackball sends data serially to the Genesis/SMS rather than parallel like the ST Mouse. The console is capable of pulling the normally high pins on the controller port to low, thus sending signals out. The Genesis uses the unconnected SMS pin 7 to strobe controllers for extra buttons. But all nine pins are connected on the Sega trackball. I assume the SMS uses a clock/latch system similar to NES controller polling to fetch the plus or minus delta value of the trackball positions. This allows of course multiple clocks per poll without losing bits of information.

 

I am tempted to just gut the PCB or pull the gray code directly off of the 7402 quad NOR chip if I can't get it to work natively with either version Marble Madness for Genesis, MD, or SMS (I could give dick about the three SMS sports titles that used it), but it appears the encoder wheels have lower precision on it. Apparently it has 16 or 18 instead of 24 teeth. I'm not sure if this would make the controller sluggish or not compared to the Atari trackballs as I have no way to accurately measure the roller diameter. If the roller is indeed smaller then they may have similar resolution. Ball is a standard 2.25 inch mottled yellow pool cue, same size as Atari.

 

Well, that's disappointing. I think everyone online who had said it works were using the actual cartridges and not ROMs off the EverDrive. Perhaps they were using a Y cable and didn't divulge that.

 

Now if both versions of the game only accepted "joystick" mode from the Sports Pad, I'd imagine the comments would mention that the control is okay but not anything about how one version reads the Sports Pad much better than the other. And that's what has been said consistently, that EA Marble Madness reads the Sports Pad much better than the Tengen Japan version. Of course, they could all be mistaken; that is possible. As for support for the Sports Pad not being mentioned in at least EA's manual, I would't read too much into that. It could've been an easter egg that the programmers put in for their own enjoyment.

 

One thing that I do find of interest…nobody has said anything about the SMS version of Marble Madness supporting the Sports Pad.

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Well, that's disappointing. I think everyone online who had said it works were using the actual cartridges and not ROMs off the EverDrive. Perhaps they were using a Y cable and didn't divulge that.

 

Now if both versions of the game only accepted "joystick" mode from the Sports Pad, I'd imagine the comments would mention that the control is okay but not anything about how one version reads the Sports Pad much better than the other. And that's what has been said consistently, that EA Marble Madness reads the Sports Pad much better than the Tengen Japan version. Of course, they could all be mistaken; that is possible. As for support for the Sports Pad not being mentioned in at least EA's manual, I would't read too much into that. It could've been an easter egg that the programmers put in for their own enjoyment.

 

One thing that I do find of interest…nobody has said anything about the SMS version of Marble Madness supporting the Sports Pad.

If the game supported it from actual cart, the ROM would work on an Everdrive assuming it is a clean dump. The Tengen Japan version is rare and expensive (but far superior audio) but the EA version is dirt cheap. And I do recall seeing it in the game menu about trackball only some such. Next time I go to Game Exchange, I'll see if they have the EA cart. I usually skip over those.

 

To do list: test the trackball in port #2. Test with the SMS Sports Pad games to make verify it functions properly in Sports mode.

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My trackball arrived a few days ago. It's a sony gb7 made for MSX computers.
post-10599-0-83349000-1448790729_thumb.jpgpost-10599-0-75410000-1448790731_thumb.jpg
It's unfortunate that the pinout is not compatible as-is with the atari, because this trackball has a custom logic chip which sends the movement since last read as a signed nybble to the joystick direction pins causing much less overhead to the console cpu. By setting a select pin high or low, the console select what axis to read. It could easily work with the 2600 by rewiring power and ground to the correct pins and by connecting the select pin to one of the paddle lines (there's already a pullup resisistor inside the trackball) so that the 2600 could select the axis by discharging the paddle caps.

Anyway, I desoldered the custom chip and a few discrete components and rewired the trackball to output the quadrature signals so it works like a st mouse. I also wired the 2 extra buttons to the 2 paddle lines, altough I didn't use pullup resistors so they cannot be read by the 2600 as-is. In this way I have all the signals on the db9 plug and I can easily build external pass-through adapters for various computers/consoles (I could put the original custom chip in an adapter as well to restore msx functionality).

I also built an adapter for atari trackball (CX22) mode unig a 74ls74 ic that I had lying around.

I briefly tested all the roms (cx22 and STmouse/cx80 versions) and it works perfectly! The response matches what BigO described in this post, and I will take actual measurements of the mechanics if I manage to find my caliper...

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Colony 7 felt a little sluggish.

Did some more hacking this weekend. I was able to tease out a double rate clock signal from the CX-53 for use with the CX22/Dir+Clk protocol and hooked it up to play some Colony 7.

 

It may come as no surprise that playing with a double speed clock made it play very much like the ST Mouse version.

 

In case you were wondering, that version seems to handle the double clock rate in stride. I didn't play long, but didn't see anything that looked like it was missing clock pulses.

Edited by BigO
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