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Protek joystick interface diagram ?

Posted: Wed Jun 03, 2020 10:19 am
by dizzy33
Hello,

I am in search of the Protek joystick interface diagram. I need to know if I can connect it along with the Erebus on the Atmos.
If you have a diagram of any other programmable joystick interface using the expansion bus (not printer bus), I may be also interested.
Thanks a lot !

Re: Protek joystick interface diagram ?

Posted: Wed Jun 03, 2020 10:34 am
by HigashiJun
I'm afraid that the best information you can find is the following one, from forum member Silicebit:

http://retrowiki.es/viewtopic.php?f=7&t=100041346

It's not so difficult to recreate the interface PCB in Eagle or Kicad, so you can give it a chance.

As already discussed in the forum, there is no way yet to make it run with another device attached to the expansion port.

Silicebit is working on a solution though...

Other available interfaces for the Oric are described in the following website:

http://www.48katmos.freeuk.com/joy.htm

Re: Protek joystick interface diagram ?

Posted: Wed Jun 03, 2020 2:30 pm
by dizzy33
Thanks. But unfortunatly there is no diagram, just a picture of the motherboard. Joysticks on the Oric are a big issue today.
In the 80's, you could use a programmable interface, like the Protek, then you could use any game with your joystick. But today, as most of us want something connected to the expansion bus (Erebus, Floppy, etc ...), we can just use a joystick on the printer port, which does not allow us to play all games, only a few of them.

So I that's why I am searching for the Protek diagram (or any other programmable interfaces), to try to guess its power consumption and some other things, to check if it will interfer with the Erebus if I connect it to the same bus at the same time.

Re: Protek joystick interface diagram ?

Posted: Wed Jun 03, 2020 3:46 pm
by HigashiJun
That's why the best thing to do (for me) would be to retro-engineer the Protek interface, unless you find someone able to provide you with the required diagrams.

As I said, you can easily reproduce its PCB with the help of the pictures you'll find in one of the previously provided links. Al the information you need is there (resistors color code, chips references, etc.).

It might be bothersome for you, but if you're interested in this interface, it could be the only solution and it's really worth it.

The good with the IJK interface (on the printer port) is that it doesn't jam the sound, and according to kenneth from this forum, it would be possible to modify some games to make them run with it...

Re: Protek joystick interface diagram ?

Posted: Wed Jun 03, 2020 4:02 pm
by HigashiJun
Oh, and I forgot, iss has also a Protek interface rebuild on its to-do list according to him.

And there's an issue he has pointed: content of the PAL chips...

I don't know if the TL866II plus would be able to read such chips. I know some of them had security fuses to prevent copycats from reading them.

I guess iss would be able to sort that issue anyway.

Re: Protek joystick interface diagram ?

Posted: Wed Jun 03, 2020 10:53 pm
by kenneth
I saw something about the Protek components...
The two chips named pal16L8 needs 210mA each and the little Ram 50mA
That means around 500mA required for the Protek interface, I think it's too much to be added with the 250mA for Erebus and 650mA for the Oric computer.
The output of the Pal16L8 connected with IOCONTROL coud be in conflict with the ouput of 74LS30 of Erebus. These outputs are not open collector made, the overcurrent may be dangerous for one of these interfaces.

Re: Protek joystick interface diagram ?

Posted: Wed Jun 03, 2020 11:23 pm
by HigashiJun
That's another potential issue to deal with... :(

As for me, the IJK interface is the best way to go by now.

Cheers.

Re: Protek joystick interface diagram ?

Posted: Thu Jun 04, 2020 12:02 am
by Chema
I've always thought the IJK interface is the only sensible way to go, even if it prevents you from using a printer (game or work, you chose :) ), but yeah, most games do not support joystick, let alone IJK, so I understand the benefits of a programmable joystick.

Surprisingly as it may seem, I've never missed a joystick to play games. I've always felt better playing with the keyboard, both on the Oric and on the Spectrum.

Re: Protek joystick interface diagram ?

Posted: Thu Jun 04, 2020 6:56 am
by HigashiJun
...and the Oric has its directional keys layout done very well. It's really nice to play Space: 1999 on it. :wink:

That said, I also like joysticks for certain games like Oricium or 1337...

Re: Protek joystick interface diagram ?

Posted: Thu Jun 04, 2020 7:12 pm
by Silicebit.
kenneth wrote:
Wed Jun 03, 2020 10:53 pm
I saw something about the Protek components...
The two chips named pal16L8 needs 210mA each and the little Ram 50mA
That means around 500mA required for the Protek interface, I think it's too much to be added with the 250mA for Erebus and 650mA for the Oric computer.
Yes too much, but the PAL16L8 could be replaced by CMOS GAL16V8 (70mA) and SRAM 2114 by the CMOS equivalent HM6148H, uPD444C or HM-6514 (7mA), no problem. ;-)
kenneth wrote:
Wed Jun 03, 2020 10:53 pm
The output of the Pal16L8 connected with IOCONTROL coud be in conflict with the ouput of 74LS30 of Erebus. These outputs are not open collector made, the overcurrent may be dangerous for one of these interfaces.
Mmmm, very bad idea not to use open collector outputs, or open drain outputs for common control lines (/IO CONTROL, /NMI, /IRQ, /ROMDIS ...) :-(

Re: Protek joystick interface diagram ?

Posted: Fri Jun 05, 2020 8:43 am
by dizzy33
Thanks to all of you for your answer (merci Kenneth !)

Re: Protek joystick interface diagram ?

Posted: Fri Jun 05, 2020 9:01 am
by dizzy33
Silicebit, would your "omnibus" project solve this problem ? Does your omnibus have its own power supply ?

Re: Protek joystick interface diagram ?

Posted: Sat Jun 06, 2020 8:52 am
by Silicebit.
Omnibus has its own linear regulator, it can supply up to 1.5Amp, and the input is protected against polarity inversion. You just need an external PSU, (7.5v to 9V 2.5Amp).

Re: Protek joystick interface diagram ?

Posted: Sun Jun 07, 2020 2:31 pm
by dizzy33
Great ! Will you build some to sell them ?

Re: Protek joystick interface diagram ?

Posted: Mon Jun 08, 2020 6:33 am
by Dbug
That seems interesting, does the omnibus also powers the Oric itself so basically we just need to power the omnibus and everything else is properly powered? If yes, how would that work with the RetroComputerShack SCART cable that's supposed to be powered for the SCART selection?