Using a TI joystick port splitter?

[TheAnachronaut]

Hello, I purchased a box of assorted VIC parts and received a Texas Instruments joystick port splitter to boot. It splits one male, Atari-style joystick port to two female ports. I’m sure someone has tried to use this to attach two sticks to the VIC. Has there ever been any success? I’m just curious. I’d love to try using it before I sell it away!
Thanks for reading! Mark

[TheAnachronaut]

I had to try it out for myself. The Texas Instruments splitter fit into the VIC nicely. Two Atari/VIC-compatible controllers fit perfectly into the female ports on the splitter! I plugged in a game (Outworld) which wouldn’t work at all.

When you look at the connector on the end of a joystick cord, you can see that all the pins aren’t being used. I wish Commodore could have figured-out how to utilize two sticks. It’s the only way that Atari’s 2600 stands above the VIC. And it does. Two player games rock. Even though the VIC has paddles, the only game that seems to use them at once is Sea Wolf, which actually is pretty dang fun though it’s graphics are simplistic.

Has anybody created any software that utilizes this splitter, or would it even be possible?
Thanks, Mark

[Mike]

I wish Commodore could have figured-out how to utilize two sticks.

They "figured it out" with the C64. Besides, I don't think it was any technical difficulty that hindered Commodore to put a second joystick port into the VIC-20. Cost was the driving factor.

Two player games rock.

Give one player the joystick, and the second player can use the keyboard. Lots of two-player games for the VIC-20 did it this way.

Has anybody created any software that utilizes this splitter, or would it even be possible?

It was rather uncommon to use peripherals across different computer manufactorers. Most people would not have expected them to be compatible (with the exception of Atari style joysticks) unless explicitly printed on the card box. Even benign looking controllers (with the same joystick plug) can shoot your VIC-20 by shorting the +5V to ground when a certain button is pressed.

That's why I don't think you will find any programs that utilise this hardware on a VIC-20.

Somewhat a standard which would allow for two extra joysticks on a VIC-20 is the so-called "4-player adapter" sold by Protovision which plugs into the userport (the naming evidently refers to the C64, where you then have 4 joysticks - but of course you get only 3 with the VIC-20). Though again, I suppose you can count the number of VIC-20 games that use it by one hand.

[TheAnachronaut]

Thanks for such a thorough reply. Can you name any joysticks capable of shorting-out a VIC? I want to avoid them!

[Mike]

Can you name any joysticks capable of shorting-out a VIC?

If you take a look at the Wikipedia article about the Atari joystick port, in the section 'Other platforms' you find a comparison of pin assignments.

All controllers that connect pin 7 (+5V on the VIC-20, see the column "VIC-20, C-64, C64GS") to something else, i.e. a button or switch, are generally out of question. This rules out the right half of the table: Amstrad CPC, MSX, Master System, Mega Drive (Genesis), Saturn and Sinclair.

[groepaz]

wow. someone copied my table from here almost verbatim

[TheAnachronaut]

Thanks for the info — I stand warned! Thanks for being gurus!