[Bought the 3DO Gamegun-Does not work]

Are you using it with an old tube TV or a flatscreen?

[TI-99/4A Hi-Tek Keyboard Replacement]

On 4/27/2021 at 6:42 PM, Nelno said:

Interested to hear any feedback. Am I wasting my time with this? Would anyone else find it useful? Has this already been done? (I couldn't find anything indicating it has when I was working on my keyboard plungers about 6 month ago).

I'm very interested in this project. I'm thinking of using a TI99/4a as a Mister/Raspberry Pi case and would need to convert/create a USB keyboard for it. I wouldn't be going for a stock look and may want to rearrange some keys.

[Troubleshooting 5200 color shadowing or color artifacts]

In case you are interested, you can get a much cleaner signal with a UAV board to output S-Video and a RetroTink Mini for S-Video to HDMI.

[READY! MODEL 100 Portable Computer Kit - Kickstarter]

On 4/23/2021 at 2:12 PM, FastRobPlus said:

Regarding the keyboard, the non-ortholinear one looks to be the common mechanical keyboard sold under the brand Royal Kludge that you can get from Amazon.  The Solar Jupiter uses this same keyboard:

This looks interesting, do you have a link about it?

 

My Googles of Solar Systems Jupiter are coming up with a lot of planets and off-grid solutions, but not this device.

 

[home made controller using variable resistors]

I don't have a schematic, but maybe this will help.

Atari 5200 FAQ -- 5200 Controller Pinout (atarihq.com)

The controllers work by putting resistance between pin 9 (Pot common which is around +5v plus or minus a volt) and pin 10 for horizontal and pin 11 for vertical.

 

The range of resistance is from about 100 ohms to 500K ohms, with 250K being about the middle of the axis. 

 

You will want to replace some of your fixed resistance with a potentiometer, which has variable resistance.

 

If the middle of the axis is 250k fixed resistance, you could change it to 200k fixed, plus a 100k pot. The 100k pot will be 50k in the middle.

This would make your controller midpoint adjustable between 200k and 300k.

 

You may want a pot with more than 100k resistance - if you can't find one you can also add capacitance to the circuit to reduce the amount of resistance you need. This is due to the way the Atari measures the resistance:

Homemade Atari 5200 Analog Controller – Dr. Scott M. Baker (smbaker.com)

 

If you have a AtariMax cart you can download Pete's Test Cart, which will show you the output of the joystick as a dot on the screen which makes it easier to test the circuit.

 

 

[If you could only have ONE, the 5200, or the XEGS?]

I'd stick with the 5200 because I have a connection with it from childhood and like the look better.

[Reset button hardware]

On 3/5/2021 at 1:30 PM, Vectrexer said:

Cool.  Did you also make a video of the removal process?  Or take pics?

 

How did you remove the old screw thread and material?

It turned out to be some superficial glue plugging the hole, no screw. I guess a previous owner tried to glue a threadless knob back on

The glue didn't join very well to the actuator which made the removal easy once I knew what I was dealing with. 

[Reset button hardware]

23 hours ago, Vectrexer said:

 

The Reset button actuator stem is hollow and threaded.  On your Vectrex the screw from the reset button appears to be broken off from the button and still inside the actuator.

 

Here are links to my YouTube and Google album videos on Vectrex control know an button removal.  As well as what the look like when removed. 

Vectrex Front Panel Controls removal for Reset Button and Power-Volume Knob - Vectrex / 光速船 / Kousokusen 

 

https://photos.app.goo.gl/i21uwDmMszxG7yge8

 

Here is a a link to the album with pictures and movie.

Vectrex Front Panel Controls removal for Reset Button and Power-Volume Knob - Vectrex / 光速船 / Kousokusen 
https://photos.app.goo.gl/uCwxAf578Kk58PkM2

 

 

Thank you. ? I was able to remove the old glue plugging my the actuator stem and screw in my reset button.

[Vectorblade order]

This is really an excellent game and deeper than it appeared at first. I was hooked when Sinistar appeared.

[Vectrex title screen]

The picture looks fine to me. Is there something in particular you don't like?

These are old analog machines, the displays have a little personality.

[Reset button hardware]

19 minutes ago, gtoal said:

Tony Lindberg in Sweden and I think Sean Kelly in the USA, maybe some others, offer machined aluminium replacements.  There are also designs on places like thingiverse for 3D printing your own (though I did try one of those myself once and it was not a good fit).

I did order a replacement, it just doesn't fit. The replacement button has a post in the middle that doesn't fit the white plastic post on my Vectrex. I edited the original post to show my replacement button.

[Reset button hardware]

My Vectrex is missing the reset button. It has a white plastic post where I assumed a nice button attached. I ordered a new button, but it does not fit on the post, it looks like the post is supposed to have a hollow center.

Pressing the post resets the Vectrex, so the actual switch seems fine. Do I have a stock part, how is it supposed to look?

[Vectrex Reboot?]

There is the Vectrex IOS app that does all this except take physical carts.

[Analog joystick resolution]

3 hours ago, Kr0tki said:

Read the "PAM Package" technical document - it's a developer's guide used internally at Atari. It describes the techniques they were using.

Great document, thanks for linking it.

[Question : Competition pro USB joystick to a 5200]

31 minutes ago, Henry Lee said:

You helped me find this :

https://create.arduino.cc/projecthub/DocSnyderde/connect-usb-joystick-to-commodore-c64-2fb5ba

I've been messing around with this idea and am using a Teensy 4.1. It is Arduino compatible and has a built in usb host.

 

Teensy 4.1 (pjrc.com)

[Building an arcade joystick for the 5200 ?]

I put a very simple circuit together shorting pin 9 to 10 and 9 to 11 through 250K resistors. This puts the dot in Pete's Test Cartridge right about in the middle as expected. But the dot jumps around a bit, maybe in an area 5x the size of the dot.

 

Is this amount of noise in the position normal or does it indicate a failing component? Is it possible to get a more stable reading?

[5200 trackball sampling rate]

The way I understand the trackball workings is that the speed you roll it produces a variable resistance on the joystick wires. My question is how long of a period the movement is sampled.

 

For example, if the ball is moved quickly for 1/200th of a second and then stopped, does the resistance remain high (or low) longer to make sure the game has enough time to sample it?

[Building an arcade joystick for the 5200 ?]

11 hours ago, Danjovic said:

up/left = 10K Ohms

down/right = 250K Ohms

middle/center = 130K Ohms

Aren't the original pots 500K? I would think center should be around 250K

[Ultimate Atari Fight Stick]

1 hour ago, Cousin Vinnie said:

I got the Atari stick- I like it, but there are some problems

However, most of the 5200 games absolutely suck on it b/c the stick doesn't behave properly. Also, I can't figure out how to map the keypad strokes to the buttons, so when I fire up realsports Baseball... all i can do is watch the computer play itself.

 

Im too old for that shit.

 

However, the physical unit itself is friggin sweet. The emulation problems Im running into is because I dont know what Im doing.

Realsports Baseball is one of my favorite 5200 games, and my favorite baseball game on any platform. It uses the keypad for pitch selection, and the analog stick for bat swing and player selection. It is probably the worst 5200 game for a product like this.

[Who's up to convert Time Pilot for the 5200???]

I'd argue to include analog control - let the 5200 shine where it can. It is already so limited compared to the arcade hardware.

Vector Pilot is analog and would be worse if it was 8-way.

[Ultimate Atari Fight Stick]

That is a pretty cool product, I've never seen it before.

The controller is missing the analog stick and the keypad buttons. A few games won't work because of that. For example, Star Raiders, Tennis and Baseball use the keypad during the game. I'm sure there are others.

Most games should work well though, probably a lot better than with funky 5200 controllers.

 

[Analog joystick resolution]

3 hours ago, Rybags said:

The resolution is limited by the hardware that reads the pots.  Pokey gives values 0-227.

Thanks for this info. I'm experimenting with a new controller for the 5200. Is there any guidance or conventions on a deadzone to use when using the joystick as a digital controller?

 

For example, if 0-113 are on the left side of the axis, and 114-227 are on the right side, is 113 considered "left" in a game like PacMan, or do games usually consider values around 113 to be null, and left isn't triggered until the value is 90 (for example) or below?

 

Or is this something each developer decides on their own?

[Analog joystick resolution]

What is the maximum resolution you can read from one of the 5200 joystick axis?

[My homemade 5200 controller]

I have a question about the pots which is related to this controller design. Forgive my ignorance of electronics and I would appreciate any corrections where I misunderstand something.

 

According to Scott Baker's blog, the digital pot maxes out at 100K resistance instead of the required 500K resistance the Atari expects. This is compensated by adding a 220nF capacitor in the controller.

 

Another way to look at it is that the digital pot has 1/5th the resistance, so will charge the internal capacitor in the 5200 five times faster. An additional 220nF capacitance must make the total capacitance five times bigger. If the internal capacitance is 55nF, then an additional 220nF will be 275nF, or five times the amount. 

 

One of my controllers has an out-of-spec pot that has 381K resistance. This will charge the capacitor 1.3 times faster than an in-spec pot. To compensate, I want 55nF * 1.3 total capacitance, or about 16nF additional capacitance.

 

Should it be possible for me to fix my out-of-spec pot by adding a 16nF capacitor, or am I misunderstanding something?

 

[Who's up to convert Time Pilot for the 5200???]

One of my favorite classic games. Time Pilot '84 was good too.