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General Category => Technical support - Hardware related => Topic started by: FruityFrank on 16:41, 28 April 25

Title: MEDL Tracking Ball - very slow
Post by: FruityFrank on 16:41, 28 April 25
Hello,
I got a MEDL trackball here. And while it works in general, its very slow. I cleaned it up but dirt wasn't the issue. 
Even when I directly turn the optical encoders, its very slow sending the keys. It 'feels' like the electronics cannot keep up with pulses from the sensor. 
Is this a known problem or is there a way to fix it? I played around with the adjustment pods but couldnt improve it.

(https://i.imgur.com/QLQQunI.jpeg)
Title: Re: MEDL Tracking Ball - very slow
Post by: pelrun on 06:09, 29 April 25
Is that purely connected via the joystick port? The CPC doesn't provide 5v on that port, unlike on most other computers which use the same connector. You might just need to power it separately.
Title: Re: MEDL Tracking Ball - very slow
Post by: andycadley on 07:54, 29 April 25
Is it even meant to be CPC compatible?

A brief search online only seems to find references to the BBC and Acorn systems. And it's worth bearing in mind that "Atari standard" joystick ports were anything but standard: once you go beyond a basic, single fire, digital joystick compatibility is far from guaranteed. Some provided analogue pins, some provide a +5V line etc. Even if they don't require those, devices may need specific software support to work as intended, you can't necessarily assume they can be seemlessly substituted for a digital joystick.
Title: Re: MEDL Tracking Ball - very slow
Post by: FruityFrank on 13:54, 29 April 25
Quote from: pelrun on 06:09, 29 April 25Is that purely connected via the joystick port? The CPC doesn't provide 5v on that port, unlike on most other computers which use the same connector. You might just need to power it separately.
It has 5v input, its daisy chained to the CPC 5v input.
Title: Re: MEDL Tracking Ball - very slow
Post by: FruityFrank on 13:56, 29 April 25
Quote from: andycadley on 07:54, 29 April 25Is it even meant to be CPC compatible?

A brief search online only seems to find references to the BBC and Acorn systems. And it's worth bearing in mind that "Atari standard" joystick ports were anything but standard: once you go beyond a basic, single fire, digital joystick compatibility is far from guaranteed. Some provided analogue pins, some provide a +5V line etc. Even if they don't require those, devices may need specific software support to work as intended, you can't necessarily assume they can be seemlessly substituted for a digital joystick.
I think its supported. It was featured in an Amstrad magazine back in the days:
cpcrulez.fr (https://cpcrulez.fr/hardware-souris-MEDL_tracker_balls.htm)

Title: Re: MEDL Tracking Ball - very slow
Post by: Prodatron on 15:12, 29 April 25
Quote from: FruityFrank on 13:56, 29 April 25
Quote from: andycadley on 07:54, 29 April 25Is it even meant to be CPC compatible?
I think its supported. It was featured in an Amstrad magazine back in the days:
cpcrulez.fr (https://cpcrulez.fr/hardware-souris-MEDL_tracker_balls.htm)

Weeske sold it for the CPC since around 9/1988, it was (first) called "Marconi RB2" and bundled with the software "Easi-Art" by Microdraw. They still advertised it in the last issue of the german CPCAI magazine end of 1992.

Before 9/1988 Weeske sold a version only for the "Schneider PC".
Title: Re: MEDL Tracking Ball - very slow
Post by: Prodatron on 16:44, 29 April 25
Quote from: FruityFrank on 16:41, 28 April 25I got a MEDL trackball here. And while it works in general, its very slow. I cleaned it up but dirt wasn't the issue.
Even when I directly turn the optical encoders, its very slow sending the keys.
Did you test it with the Easi-Art software? Maybe it has to be polled very fast to give a useful output.
Title: Re: MEDL Tracking Ball - very slow
Post by: FruityFrank on 17:37, 29 April 25
Quote from: Prodatron on 16:44, 29 April 25
Quote from: FruityFrank on 16:41, 28 April 25I got a MEDL trackball here. And while it works in general, its very slow. I cleaned it up but dirt wasn't the issue.
Even when I directly turn the optical encoders, its very slow sending the keys.
Did you test it with the Easi-Art software? Maybe it has to be polled very fast to give a useful output.
not yet, but will give it a try tomorrow. I wanted to use the Trackball in SymbOS :) 
Title: Re: MEDL Tracking Ball - very slow
Post by: GUNHED on 20:51, 29 April 25
Quote from: FruityFrank on 16:41, 28 April 25Hello,
I got a MEDL trackball here. And while it works in general, its very slow. I cleaned it up but dirt wasn't the issue.
Even when I directly turn the optical encoders, its very slow sending the keys. It 'feels' like the electronics cannot keep up with pulses from the sensor.
Is this a known problem or is there a way to fix it? I played around with the adjustment pods but couldn't improve it.
Hi there, that's a great expansion. Actually I use it too from time to time.
The software needs to be compatible to the trackball. It's the same for the AMX mouse. Use the designated software and you will like it very much.  :) :) :)
Title: Re: MEDL Tracking Ball - very slow
Post by: FruityFrank on 19:26, 30 April 25
Quote from: Prodatron on 16:44, 29 April 25
Quote from: FruityFrank on 16:41, 28 April 25I got a MEDL trackball here. And while it works in general, its very slow. I cleaned it up but dirt wasn't the issue.
Even when I directly turn the optical encoders, its very slow sending the keys.
Did you test it with the Easi-Art software? Maybe it has to be polled very fast to give a useful output.
Its appears to work fine in easiArt, speedwise i mean.
Will try in SymbOS 4 later. So far I only ran v3. Missed that there was an update :O 
Title: Re: MEDL Tracking Ball - very slow
Post by: GUNHED on 14:16, 02 May 25
Let us know how it works!  :)
Title: Re: MEDL Tracking Ball - very slow
Post by: FruityFrank on 15:43, 03 May 25
It works, kinda. But its not really useable since the speed of the mousecursor doesn't relate to the speed you move the trackball with.
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