ComCon joystick interface on the 128k

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NeoStuey
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Re: ComCon joystick interface on the 128k

Post by NeoStuey »

Thanks Ast A. Moore.

ahh! That's my bad and you are right I didn't count the key slot as a pin so as you say I miscounted.

I don't have the necessary components to hand to try that out and would also be interested to see if this was the fix Frel Ltd implemented their mod.
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Ast A. Moore
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Re: ComCon joystick interface on the 128k

Post by Ast A. Moore »

NeoStuey wrote: Thu Feb 08, 2018 8:00 pm I don't have the necessary components to hand to try that out
Any resistor around that value will do: 390, 470, 500, 510 Ohm. For the purposes of testing, you don’t even need to desolder the lead from lower pin 13. Simply wiggle a resistor between it and upper pin 17 (making sure you don’t short anything). Hook the interface up to the Toast Rack and see if it works. If it does, you can think of a more permanent solution, in which case you’ll need to lift pin 13 entirely and leave it unconnected.

Again, I make no promises. ;)
Every man should plant a tree, build a house, and write a ZX Spectrum game.

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and zasm Z80 Assembler syntax highlighter.
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NeoStuey
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Re: ComCon joystick interface on the 128k

Post by NeoStuey »

Ast A. Moore wrote: Thu Feb 08, 2018 8:51 pm
NeoStuey wrote: Thu Feb 08, 2018 8:00 pm I don't have the necessary components to hand to try that out
Any resistor around that value will do: 390, 470, 500, 510 Ohm. For the purposes of testing, you don’t even need to desolder the lead from lower pin 13. Simply wiggle a resistor between it and upper pin 17 (making sure you don’t short anything). Hook the interface up to the Toast Rack and see if it works. If it does, you can think of a more permanent solution, in which case you’ll need to lift pin 13 entirely and leave it unconnected.

Again, I make no promises. ;)
THANK YOU!

As I didn't have any resistors but couldn't resist trying I ran a small piece of insulated wire from pin 13 underside to pin 17 topside and plugged it all in (with more than just my fingers crossed). And now I can confirm the Comcon inputs were detected as key presses as desired and I know I know how to overcome the hurdle I had I will return to mod it permanently once I have the necessary components to hand. At Least now I know I can play Escape from the planet of the Robot Monsters with a joypad now and older titles like Stop the Express.

Thanks again for the input and your time helping me with this.
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Ast A. Moore
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Re: ComCon joystick interface on the 128k

Post by Ast A. Moore »

NeoStuey wrote: Fri Feb 09, 2018 9:08 pm As I didn't have any resistors but couldn't resist trying . . .
I see what you did there. ;)
NeoStuey wrote: Fri Feb 09, 2018 9:08 pmThanks again for the input and your time helping me with this.
Hey, no problem. I’m glad my hunch was too far off the mark.
Every man should plant a tree, build a house, and write a ZX Spectrum game.

Author of A Yankee in Iraq, a 50 fps shoot-’em-up—the first game to utilize the floating bus on the +2A/+3,
and zasm Z80 Assembler syntax highlighter.
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RMartins
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Re: ComCon joystick interface on the 128k

Post by RMartins »

NeoStuey wrote: Thu Feb 08, 2018 7:04 pm ...
RMartins any chance of popping open a Comcon, just four screws and no glue to worry about perhaps we could compare PCBs and any additional features?
...
Eventually, I could, but currently all 3 I own are in the storage room, and not that easy to access, since my last scavenging ... :D
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Luzie
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Re: ComCon joystick interface on the 128k

Post by Luzie »

NeoStuey wrote: Wed Feb 07, 2018 10:54 pm Here's the only snippet of information about said mod I can find from Crash April 1986.

Frel have cornered the market for mechanical interfaces: their Comcon interface costs a whacking E19.95, but it is fairly durable and has a through port so you can use the sound boosting features of the Turbo Ace at the same time. The only snag is that the Comcon won't work with the Quickshot 2 rapid fire option. Frel are at 1 Hockeys Mill, Temeside, Ludlow SY8 1PD. The standard Comcon won't work with the 128K machine (Frel will upgrade it for a fee of f4.00). but a new version which is compatible with both machines is on the way.
Just for completeness: Yes, this is on Page 108: https://archive.org/details/crash-magaz ... ew=theater
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