8bitAndy

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

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.

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.

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.

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.

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

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.

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

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

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.

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.

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?

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

Great document, thanks for linking it.

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)

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?

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?

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

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.

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.

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.

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?

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

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?

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