possible? seperate axis for TM GP-1?
Michael Koon
I was given an old Thrustmaster Grand Prix-1 steering wheel. Is it possible
to put the brake and gas paddles on separate axis? Do I need a separate
adapter> I am currently using the port on my sound card and win98,
thanks
koondog
Michael E. Carver
% Hi
% I was given an old Thrustmaster Grand Prix-1 steering wheel. Is it possible
% to put the brake and gas paddles on separate axis? Do I need a separate
% adapter> I am currently using the port on my sound card and win98,
You will need to rewire your unit to accomplish this. The following is
an old post from r.a.s. about doing this for the T2. You should be able
to do something similar to your GP1.
From: jsi...@spam.not.welcome (LavaBoy)
Newsgroups: rec.autos.simulators
Subject: Re: Seperate axis on a T2? (long)
Date: 7 Oct 1998 20:48:44 GMT
In article <tMFS1.23486$K02.13...@news.teleport.com>,
<mca...@teleport.com> wrote:
>On Thu, 1 Oct 1998 13:37:51 -0500 Scott Moore <smo...@dnsonline.net> wrote:
>% After lots of practice with GPL, I think a seperate brake and throttle =
>% axis would be a great help. Does anyone know of a way to accomplish this =
>% with a T2? I'd certainly like a NASCAR Pro, but my money is going to =
>% system upgrades(16 FPS in traffic ain't cutting it :-) ). Any help on =
>% this issue is appreciated.
>
>I have heard (haven't verified it) that the T2 doesn't have the
>necessary wires in its cable. So you will need to get new cabling and
>connectors to pull this off. But check out Lew's Wheels for a great
>schematic <http://www.monmouth.com/~lw4750/electric.htm>
That is partly true, you end up having to add 1 wire that runs from your
pedals to the joystick jack along the pedals joystick chord.
I just dug into the connector to find what color wire at right pin, then
spliced into it earlier in the cable.
Not too terribly hard a project if you are familiar with soldering, I did it to
my old style T2 (which uses the adaptor in Win95), thanks to the terrific
info provided by another newsgroup reader to me when I asked this same
question here sometime last year.
Below is the e-mail he sent back to me which I used with great results,
your mileage may vary. Big thanks to Grant Reeve again for providing
me with the details on how to do this. I hope he doesn't mind me posting
the info here for all to benefit, I tried to verify by mail but never
reached him. I snipped the e-mail addresses to protect the innocent from
SPAMBOTS. This is especially useful with GPL, and really improved my ability
to trail brake!
Hope this helps other T2 owners out there who are not too afraid to try this,
but please do this at your own risk, we take no responsibility if this doesn't
work for you and you end up messing up your wheel. My T2 was pretty old anyhow.
<insert standard disclaimer>
--John
---Cut here----
Email Message From: Grant Reeve
Hi John :)
At 14:25 16/04/98 -0700, you wrote:
>I posted a response on the r.a.s. newsgroup but also sending you e-mail
>in case you don't see it. Posting there would probably help people in
>the future if they look up this info on Dejanews, but if you would like
>to e-mail me the info instead that is fine also.
>
I haven't looked at r.a.s yet today so i guess i haven't had a chance to
see your message there as yet. I'll reply in email anyway.
>I have a T2 with the old style (I have to use the adaptor) Joystick2
>pedal axis.
>
same here, but all the difference really is is that pins 6 and 11 are
swapped by the adapter, while the newer T2's have pins 6 and 11 wired
the right way around in the first place.
>I'm wondering how difficult it was just to split the pedal axis?
>
as long as you're OK with soldering stuff it should be fine. Also it helps
to have a multimeter or something to check which wires are connected to what
and stuff.
>Did you need to run any new wires into the pedals or just rewire the
existing?
>I have replaced both pedal pots in the past and my guess would be that
instead
>of the two pots being wired in series as they are by default you would
>just wire them independent +5v to each pot?
>
I run an extra wire from the pedals to the plug since there's no spare wires
in the cable.
You can use the same +5v. you split the wire connecting them in series to
another joystick axis, and attach a second +5v to the other pot which
didn't have a +5v wire.
>Please pass on the details to the splitting process, I think splitting the
>two pots would eliminate much of the jumpiness I see in my pedal axis.
>
You'll probably find the jumpiness is still there. I do.
ok, after this is a rather large set of details on what i did, whcih i
wrote the other night to someone else but it's easier to just cut and
paste because it applies in general:) He made a comment that my second
ascii wiring diagrams should be labled "Friendly Pedal Guy" and "Friendly
Pedal Guy with Strange Hat" :)
---------------------
What I have done is used a double pole double positon switch to allow
me to switch between both pedals on one axis (the normal one), and
the pedals on two seperate axiis. It works very well.
I've got one of the older T2's that requires an adapter, so the two normal
axiis it uses are Joystick 1 axis 1 for steering, and Joystick 2 axis 1 for
pedals. The adapter simply passes through all the pins, while swapping
Joystick 2 axis 1 with Joystick 1 axis 2. So with all the wiring i did, i've
used both pedals on J2-A1 (Joystick 2 axis 1 - will save me typing!), and
when split, the gas on J2-A1 and brake on J1-A2, knowing that the adapter
swaps them over. If you have a newer T2 you'll be wanting to swap all wiring
to the right pins from the start.
I see you're referring to axis 0 instead of axis 1 like i am:) so when i say
axis 1 i guess i'm meaning your axis 0.
The switch i made, when it has the two pedals on one axis, also connects
the +5v pin directly over to J1-A2 so that there is some kind of reading
on this third axis, which means i can flick the switch and recalibrate,
just like that, voiding any need to fiddle around with removing the 3 axis
joystick from the Win95 control panel and adding a 2 axis one and back again
all the time.
I am not entirely sure if it's healthy to connect the +5V directly to a
joystick axis like that - but this is the equivalent of no resistance,
so i would expect it to be fine. Maybe we should wire a 36 KOhm resister
instead of just a direct +5V connect.
You will have to hack'n'slash into the plug at the computer end of the
T2 cable, it's molded plastic that has probably melted slightly and fused
with the black outer casing of the two cables going into the plug. But that's
the only part that's fused so I was able to cut open the molded casing of
the plug relatively cleanly at that end to cut it away from the cables, then
i was able to slide it off revealing the gory horror of the innards of the
plug. Gory, because they've encased all the wiring and stuff in a soft
plastic, which makes it bloody painful to get access to wires and things!
More on this later in the email.
I've cut a nice little notch in the side of my pedal base about 5cm from
the cable out, where i will mount the switch properly, but I don't have
small enough screws for the switch as yet so i just have the switch dangling
loose.
OK I suppose you're wondering where all the wiring diagrams are and stufF:)
well, i've been writing all the other bits first because i was being lazy.
I based all this on some info i found at some guy's web page, i think it
might have been called "wally's world of sims" or something, but i ended
up using my own wiring and stuff, because he had a lot of unneccesary
crap, and felt like improving it to suit myself.
First i'll give a pin-out of the joystick port, for your usual soundcard:
Pin | Description
1 +5 V
2 Joystick 1 Button 1
3 Joystick 1 Axis 1
4 common ground for buttons
5 common ground for buttons
6 Joystick 1 Axis 2
7 Joystick 1 Button 2
8 +5 V
9 +5 V
10 Joystick 2 Button 1
11 Joystick 2 Axis 1
12 MIDI TXD
13 Joystick 2 Axis 2
14 Joystick 2 Button 2
15 MIDI RXD
Naturally we're ignoring the MIDI pins.
If you're T2 is a newer one without the adapter, please swap all my
references to pins 11 and 6.
OK, here is a really corny ascii diagram of how the wiring currently
is configured in your T2 pedal base. I hope you've got a fixed-width
font in your email program:)
btw - all references to pin 8 here actually only mean "+5V". Since
there's 3 +5V pins it could really be any one of them, it doesn't matter.
______________
/ \
| ___ | ___
X-/ \ X-/ \
gas | G | | B | brake
X-\___/ X-\___/
| |
| \_
| \
/ |
/ |8
/ |
/ ----------------|--
| 1 \ o o o o o o o X / 8
| 9 \ o o X o o o o / 15
| -----|---------
| |
\__________/11
And now here's the wiring with the double position double pole switch
wired in. When the switch is in the Left position, the axiis will be
on one axis going to pin 11, with a fixed resistance going to pin 6.
When the switch is in the Right position, the axiis are split, gas on
pin 11, brake on pin 6. If you trace all the wiring you should understand
how the wiring is all done. Let me know if it's confusing or the diagram
is a mess or something.
The wires don't actually connect where they are crossing over each
other, btw.
/--------------\
| _______|___________
| / | \
| /-|-------|-\ /+\
| | X X X | | | 36 KOhm resistor or thereabouts
| | \ | \+/
\------X X \ X-----------/
\-|---|-|-|-/
switch | | | |
\___|_|_|__
_______/ | | \
/ | | |
| ___ | | | ___
X-/ \ | | X-/ \
gas | G | | | | B | brake
X-\___/ | \--X-\___/
| | |
| | \_
| | \
/ | |
/ \__6 |8
/ \ |
/ ------------|---|--
| 1 \ o o o o o X o X / 8
| 9 \ o o X o o o o / 15
| -----|---------
| |
\__________/11
The switch basically is inserted into the wire that currently
connects the two pots together.
I hope you're comfortable with lots of soldering and desoldering:)
and do you have a multimeter or something to check where wires are
connected to and from?
Now once I put the switch in, i had this extra wire I needed to connect
to pin 6 at the plug. This wire is pretty long, i've run it the length
of the current cable, using tape to hold it in place. This is where i
had to spend a couple of hours cautiously hacking away at the plug to
figure out just which wire that came out of the cables ended up at pin 6,
because with all the wires buried in that soft plastic you can't just
look. I used a razor sharp cardboard knife thingy to slowly cut away
the plastic until i had burrowed down to the solder connection of pin 6
itself, and took a look at the colour of the wire that was soldered to it.
It was the black wire, in my T2 wiring, and very very conveniently, the
black wire was the topmost one in the bundle of wires that came out of
the thicker cable that runs to the plug where you plug in the wheel unit.
I then cut that black wire where it emerges from this cable, and soldered
my wire to the cut off wire - this was easier than trying to dig out enough
plastic aound pin 6 to try and solder my wire directly to pin 6.
Sounds like a bit of a mission, doesn't it?:) it took me over 12 hours
from start to finish to get all this done, with a lot of being very
cautious, and checking all the wires and stuff with my el-cheapo multimeter
to make sure i had the right wires and stuff.
It might be an idea to simply rewire an entirely new plug.
OK, i think that's all the hardware side of it. I hope i haven't forgotten
any of it.
Now the next fun part comes with trying to get stupid games and stuff
to calibrate with the split axiis. It's a bit less easy now.
Calibrating for Win95 stuff:
- Go into Thrustmaster's Propanel, add a Nascar/Formula Pro w/seperate pedals.
- Quit Propanel straight away, because the stupid thing can't calibrate it.
- Run the Win95 joystick control panel and calibrate the wheels and pedals.
- Quit the Win95 joystick control panel.
- Rerun the Propanel, click on the little wheel to look at the configuration
of the current joystick, and then test the calibration, and close it.
This is to get the Propanel to tell Win95 to use it's joystick routines,
which work better than the win95 ones. but Propanel is stupid and can't
calibrate the seperate pedals properly so we have to do it this way. well,
i do anyway. maybe there's a new propanel i don't have.
Calibrating for other games like Nascar2, SODA, GPL, etc:
- dead simple! works perfectly.
Going back to 2 axis instead of 3 axis:
- flick the switch.
- recalibrate. (no need to switch back to a 2 axis joystick)
- it works!
Problems:
The only problem i have is due to I think my Soundcard having shit inaccurate
measurement of the resistances of the axiis. As the total combined resistance
of all the pots increases, the measurements begin oscillating more and more.
If i have the brake unpressed, the gas depressed, and the steering all the
way left, this is the minimum total resistance, and the oscillation is only
1% or so, at maybe 2Hz. When i reverse all those axiis to get maximum
resistance, the oscillation goes up to around 4% of the values, at about
15-20Hz. This is bloody useless as far as i am concerned. It should not
be doing this! I think a dedicated gamecard would be the solution? I am
not sure about this solution. I know it's not the pots beacuse the
oscillations vary according to all the pots combined, and the oscillations
on all axiis are always in sync with each other. must be the soundcard.
This oscilliation is where my problems come in. Apart from not being
as accurate as the wheel could be, it makes it very difficult to get a
constant center for the accelerator pedal, which has a high resistance when
it is not depressed. So i find the value to be oscillating by about 2-3%
or so around the pedal center. This gets very irritating in F1RS because
it keeps oscillation from zero pedal to a teeny amount of pedal and it
starts accellerating the car when i have no pedal pressed, and it can
actually push the car along at 110kph when i am not pressing the pedal!!!
I think if you fiddle with calibrating it eventually it'll work better. It
depends on where in the oscillation wave displacement it was when you hit
the button for "this is center". if it's at the far end of the wave, the
oscillation is always in the very low pedal movement area. if you catch it
at the other end, the oscillation is on the far side of the pedal center
and thus is ignored for being negative.
But then that's where the problem kicks in with SODA. SODA looks at the
Joystick 1 y axis for menu movement, even though i've calibrated for
seperate pedals! so when the pedal oscillations are on the far side of
the gas pedal center, because there is basically no range at all to this
negative side of the axis, this tiny 3% oscillation gets interpreted as
full range movement and the damn menu selector is constantly tearing off
downwards unless i hit the gas pedal a tiny amount. I solve this by
calibrating SODA over and over until i happen to get the oscillation sitting
just on the postive side of center, where it's range of movement is tiny
compared to the size of the full pedal's movement.
I hope that made sense:)
OK, hopefully i've given you enough information (hell i damn nearly wrote
a small novel here!) on what i did that you can do the same. Once it gets
calibrated well, it's awesome:)
Good luck with your pedal extensions!
Grant.
--
**************************** Michael E. Carver *************************
Upside out, or inside down...False alarm the only game in town.
mca...@teleport.com http://www.teleport.com/~mcarver
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