4 replies to this topic

[ledzep]

I haven't been able to find much on this subject. Maybe I've just been looking in the wrong places. In either case, I'm just wondering if a Vectrex can be programmed to use an Atari trackball controller like the CX22 or CX80 in trackball mode. I'm guessing that since the Vectrex joysticks are analog and seem to function like Atari 5200 sticks (two pots) that the Vectrex could be made to understand trackball output. But I'm sure I'm assuming it's simpler than it actually is otherwise I would expect to have seen a Vectrex homebrew by now that utilized the Atari trackball.

Also, can the Vectrex read the output of an Atari keyboard controller? That seems pretty straightforward to me but I've never tried to program a Vectrex so I don't know what one of those droids is expecting to hear from the controller ports. I ask because I have a copy of the old Tsunami homebrew game and the instructions include a section on converting a Vectrex controller to use an Atari driving controller as a cheap spinner so I assume that the driving controller or a paddle controller must be pretty basic compared to the trackball and keyboard controller.

Has anybody ever figured that out and written it down somewhere? Thanks in advance for any info.

[Rybags]

5200 trakball outputs an analog value for the X and Y axis, so in theory could be used on another system that has analog joysticks. Although the pot values can be different, e.g. Commodore uses 500K, Atari 1M.

Keyboard controllers need 4 output bits so that you can select a column. Then each of 3 keys on that column can be read, one on the joystick trigger and the other 2 through each paddle (Pot) input.

2600/7800/computer trakball works with the same principle as an ST or Amiga mouse. 2 bits of joystick directional input are assigned to the X and Y axis each. Bits go through a sequence according to movement direction, you need to sample probably at a minimum of 100 per second to get accurate tracking.

[Bruce Tomlin]

They may both use 9-pin ports, but they are wired completely differently.

[ledzep]

Bruce Tomlin, on Mon Aug 16, 2010 1:08 PM, said:

They may both use 9-pin ports, but they are wired completely differently.

That much I assumed but I was wondering, if they were wired correctly to each other (meaning ground to ground, power to power, etc.), if the Vectrex could be convinced to use the data coming out of an Atari CX22 trackball or keyboard controller. The reason I ask is because apparently a driving controller can be used with the Tsunami homebrew so that seems to say that it's possible to wire in other controllers to be usable by the Vectrex. But I don't know what the limits of that console are.

So I was wondering if it could be possible to wire in a trackball and the Vectrex could even read and store what was coming out of it or would it just be useless noise. I've never programmed anything for a Vectrex so I don't know what its hardware will accept, if wiring in the trackball would be feeding data to the Vectrex's registers such that it becomes the programmer's problem to make sense of what is being read or if it's the case that no matter what is wired to what the Vectrex will never understand what it's being sent. From what I've read there are 4 pins for the fire buttons, 1 pin for each pot, a +5V, a -5V and a ground. Can a board be wired up to convert trackball gray code into the equivalent of +/- voltages?

I'm sure I'm probably asking questions that are so dumb that it's hard to even explain how dumb they are. I'm just thinking in terms of what if GCE had decided to make a trackball controller for the Vectrex in order to play games like Centipede and Missile Command (if it had stayed around long enough) that would have come out eventually. Would GCE have had to scrap the idea because the Vectrex was simply not capable of accepting a trackball (I find that hard to believe considering they managed to make a color-wheel 3D viewer work) or would they have had to make a special trackball with a daughter board that converted gray code to analog joystick voltages?

[Desfeek]

ledzep, on Mon Aug 16, 2010 11:55 PM, said:

Bruce Tomlin, on Mon Aug 16, 2010 1:08 PM, said:

They may both use 9-pin ports, but they are wired completely differently.

That much I assumed but I was wondering, if they were wired correctly to each other (meaning ground to ground, power to power, etc.), if the Vectrex could be convinced to use the data coming out of an Atari CX22 trackball or keyboard controller. The reason I ask is because apparently a driving controller can be used with the Tsunami homebrew so that seems to say that it's possible to wire in other controllers to be usable by the Vectrex. But I don't know what the limits of that console are.

So I was wondering if it could be possible to wire in a trackball and the Vectrex could even read and store what was coming out of it or would it just be useless noise. I've never programmed anything for a Vectrex so I don't know what its hardware will accept, if wiring in the trackball would be feeding data to the Vectrex's registers such that it becomes the programmer's problem to make sense of what is being read or if it's the case that no matter what is wired to what the Vectrex will never understand what it's being sent. From what I've read there are 4 pins for the fire buttons, 1 pin for each pot, a +5V, a -5V and a ground. Can a board be wired up to convert trackball gray code into the equivalent of +/- voltages?

I'm sure I'm probably asking questions that are so dumb that it's hard to even explain how dumb they are. I'm just thinking in terms of what if GCE had decided to make a trackball controller for the Vectrex in order to play games like Centipede and Missile Command (if it had stayed around long enough) that would have come out eventually. Would GCE have had to scrap the idea because the Vectrex was simply not capable of accepting a trackball (I find that hard to believe considering they managed to make a color-wheel 3D viewer work) or would they have had to make a special trackball with a daughter board that converted gray code to analog joystick voltages?

http://www.playvectrex.com/

go to 'VecTech' on the sidebar

scroll down to 'controllers'

first controller mod listed - 'Modified Atari 2600 Paddle "Pong" Controller' - there is your answer!

I have seen a few different modded controllers for Vectrex. I have a PX1 Arcade stick and a SNES controller modded to work with Vectrex, and I have seen lots of converted Genesis gamepads. Its a minor modification to make a universal DB9 to work with a Vectrex DB9