PC mouse to QL conversion project

Nagging hardware related question? Post here!
User avatar
Dave
SandySuperQDave
Posts: 2429
Joined: Sat Jan 22, 2011 6:52 am
Location: Austin, TX
Contact:

Re: PC mouse to QL conversion project

Postby Dave » Mon May 06, 2019 8:28 pm

We only had like 3 upgrades ever, so I probably did that upgrade for you.

I did not like the mice at ALL. They were flimsy, lumpy in rolling and required repeated cleaning to even function. I found roughening the spindles slightly helped them a bit, but you can't go modding new gear to sent to customers just because.


tcat
Super Gold Card
Posts: 558
Joined: Fri Jan 18, 2013 5:27 pm
Location: Prague, Czech Republic

Re: PC mouse to QL conversion project

Postby tcat » Wed May 08, 2019 6:23 am

of-mice-and-men-but-mostly-mice

J.Steinbeck unpublished sequel :-)
When no QIMI board is available then the only option are very old serial mice. It's possible that the QL has to be modified (a resistor bridged) as otherwise only 10mA is available on the serial port.
Marcel


Hi Marcel, can you please be more specific about the resistor, as I use serial mouse and I do not get the idea yet. Has this mod been applied, do you have a picture inside QL?

Many thanks
Tom


tcat
Super Gold Card
Posts: 558
Joined: Fri Jan 18, 2013 5:27 pm
Location: Prague, Czech Republic

Re: PC mouse to QL conversion project

Postby tcat » Wed May 08, 2019 6:35 am

Hi Cristian,
Atari ST mice are compatible with QL + Sermouse.... can anyone confirm?

I think ST mice plugs to QIMI interface, while SerMouse expects a Serial mouse plugged to QL's SER{1,2}

The process seems rather simple, if you have some basic soldering skills.
Here is the link:
http://oldcomputer.info/hacks/mouse/index.htm

Very good project, it feels almost matching my simple soldering skills, no SMD.

I wish to complement with my find about various mice makes.
http://www.tcocd.de/Pictures/Peripheral/in_mice.shtml

Ciao
Tomas


User avatar
mk79
Gold Card
Posts: 399
Joined: Sun Feb 02, 2014 10:54 am

Re: PC mouse to QL conversion project

Postby mk79 » Wed May 08, 2019 9:14 pm

tcat wrote:Hi Marcel, can you please be more specific about the resistor, as I use serial mouse and I do not get the idea yet. Has this mod been applied, do you have a picture inside QL?
I don't have a picture. But it's R10, it's between the serial ports and the TV modulator. It has 680 Ohm so you can only pull 17mA out of the 12V lines of the RS232 ports. One can solder a bridge or at least another resistor over it to increase the value.

Marcel


tcat
Super Gold Card
Posts: 558
Joined: Fri Jan 18, 2013 5:27 pm
Location: Prague, Czech Republic

Re: PC mouse to QL conversion project

Postby tcat » Thu May 09, 2019 9:19 am

Hi Marcel,

Bridging the resistor, as a side effect, would it hook SER1 to SER2 data incoming queue?
Apologies for not getting it yet.

Tomas


User avatar
mk79
Gold Card
Posts: 399
Joined: Sun Feb 02, 2014 10:54 am

Re: PC mouse to QL conversion project

Postby mk79 » Thu May 09, 2019 1:20 pm

You can draw more power out of it. And mice need power. No other magic properties.


Nasta
Gold Card
Posts: 339
Joined: Sun Feb 12, 2012 2:02 am
Location: Zapresic, Croatia

Re: PC mouse to QL conversion project

Postby Nasta » Thu May 09, 2019 2:12 pm

a serial mouse needs power just like anything else, but there is no direct way to get power from the serial port.
So, the mouse uses a trick - most of the time, any output line on the serial port is at a high voltage level (~10V usually), and since the serial mouse normally just sends data, it has no use for the lines that are output on the serial port, only input. So, it uses these lines to draw power from them.

Normally, there are 3 output lines, the transmitted data and two handshake lines. One of the lines is used by the receiving section of the port so cannot be relied upon because it controls the flow of data from the mouse, and the other is usually always high as long as the computer is powered on. However, on the QL this one is 'fake', it's just the 12V power supply through a resistor. It was basically done to be compatible, not to source power. As a result, some serial mice will not work because there is not enough power through the available lines.

It is possible to improve this situation by reducing the value of the series resistor, this is normally 680 ohms. About hlf to 1/3 would be a better value, BUT I would not replace the resistor with a jumper as an accidental short on the line might kill the 12V regulator on the motherboard.
Instead, a 390 ohm resistor can be soldered in parallel to get about 2.5x the current which should be enough for the mouse.

BTW on the upcoming motherboard ISS8 there is no 12V power supply so the same serial line is driven from the 9V input power. Since this would possibly make the problem worse, a current source is provided that provides up to 50mA of current out of that pin and also limits the maximum current to that amount so the pin is short-circuit safe.


tcat
Super Gold Card
Posts: 558
Joined: Fri Jan 18, 2013 5:27 pm
Location: Prague, Czech Republic

Re: PC mouse to QL conversion project

Postby tcat » Thu May 09, 2019 4:52 pm

Hi Nasta,

Thank you for explaining. My serial mouse just seems doing things. I cannot tell whether R10 has been bridged, but I am led to believe the model I have draws some 10mA or so, but I may well be wrong.

My mouse connects to SER1, while Linux host to SER2. What has troubled me so far, is that incoming mouse data on SER1 appears also in SER2 input queue. I have not been able to figure out why.

It happens only SER1 => SER2 direction.

COPY SER1 TO SCR_
draws some patterns on the screen as the mouse moves, however so does
COPY SER2 TO SCR_

My QL is Iss#6,
JS-ROM ,
TKII v1.12 toolkit,
original IPC.

Any idea?
Many thanks
Tomas


User avatar
mk79
Gold Card
Posts: 399
Joined: Sun Feb 02, 2014 10:54 am

Re: PC mouse to QL conversion project

Postby mk79 » Fri May 10, 2019 4:02 pm

tcat wrote:My mouse connects to SER1, while Linux host to SER2. What has troubled me so far, is that incoming mouse data on SER1 appears also in SER2 input queue. I have not been able to figure out why.
That I can easily answer. The two receive lines are internally connected, the hardware cannot distinguish between them. My question is more how the QL was ever supposed to separate SER1 and SER2. I can only imagine toggling the handshake lines and multiplexing the combined receive line to the one that currently has an active handshake or something like that.

Marcel


User avatar
Dave
SandySuperQDave
Posts: 2429
Joined: Sat Jan 22, 2011 6:52 am
Location: Austin, TX
Contact:

Re: PC mouse to QL conversion project

Postby Dave » Fri May 10, 2019 5:16 pm

When the DUART driver is working, I would be quite happy to have SER1_ and SER2_ replaced by the DUART. Currently the plan seems to be to add SER3_ so that it can replace the SER3_ on SuperHermes. "SER4_" might instead be a separate device type ESP_ for access to an ESP32.

Transfers with a PC would be at least 10x faster, and with proper handshaking and buffering.

Separately, we're still discussing the option of replacing the QIMI socket with an InPort socket (mini-DIN9) so that any PC bus mouse can be used directly, without adaptors. PC mice are still generally available and cheap.

If anyone has any opinions on that, we're listening.



Who is online

Users browsing this forum: No registered users and 5 guests