Spy Hunter Gas Pedal Calibration Help

[Greg Baumgratz]

I have my steering centered and calibrated, but I can't seem to get the
gas pedal working properly. Anyone with some schematics and thoughts
care to comment on this one. I'll put it in writing and maybe it will
help me reason it out. Feel free to comment.

I could not get the correct 'at rest' value in the calibration screen by
using the rotational adjustments on the pot mounting. I removed the
pot, figuring that someone had replaced it without properly calibrating
it. By spinning the pot, I am able to get the correct value of 0E (if I
remember correctly) and can set it this way. Problem is, at this
adjustment, it is near the end of it's travel and only allows for a
little acceleration when coined up and tested. So, aren't the readings
for the steering and gas pedal both taken through the same A/D
converter, so if the steering calibration works, doesn't that mean the
area between the A/D converter and the uProcessor are working - or are
the values for the two somehow separated on the SSIO board later and I
have a problem there?

Time to get back to the schematics... Anyone care to help out on this one?

Thanks,
Greg

[Douglas Paterson]

I'm NOT an expert, but here's what I've done wrt calibration:

I use the calibration screen to set the neutral point, then play from there.
It means I have to calibrate every time I power up. I don't know if this is
the "right" way to do it or if it's just a work-around, but it DOES work (on
mine, the issue is the same as yours--unable to get full acceleration).
Hope this helps.

--
Doug
"Where am I to go/Now that I've gone too far?" -- Golden Earring, "Twilight
Zone"
(my email is spam-proofed; read the address and make the appropriate change
to contact me)

"Greg Baumgratz" <rgvac...@galaxian.com> wrote in message
news:41352B8C...@galaxian.com...

[Zinfer]

This is probably not related to calibration, but does your steering
wheel have 1 or 2 springs? I've got two Control Panels and they both
only have 1 spring where it looks like there is also another hole
where a 2nd spring should go.

Rod's Arcade Restoration
http://www.kineplex.com

[Mickey Johnson]

asked and answered many times before.

google is your friend

--
Mickster

Visit my website and see my arcade!!

http://mickster.freeservers.com

"Zinfer" <rmas...@hotmail.com> wrote in message
news:4135b379...@news-server.woh.rr.com...

[Greg Baumgratz]

OK smart guy - read the rest of my post and then answer with something
worthwhile. The standard calibration method - which by the way, I did
research and do, is not working. There is a problem either with the
absolute position board or SSIO.

Thanks for your help and flame on.

~Greg

[Greg Baumgratz]

Wow - if that's not an open mouth insert foot post archived for all of
time, I don't know what is... Anyway, I just realized he wasn't
responding to my post.

My apologies if that means anything - oh and still flame on if need be...

~Greg

(still trying to remove foot from mouth
'cause it's lodged in there pretty good)

[default_dave]

Yup that's what i do as well. infact, before i shut down the game i
flick it into test mode so the next time i power it up it's already in
test mode for a re-cal. my steering wheel's at like 77 or 70 when
physically centered [instead of 7E or whatever] lets just say if i
don't center it, it pulls to the left pretty bad.

the Gas pedal:
if you've taking the Pot off then it's a little harder now because
it's tough to get the right 'throw' with the values you want. i'd get
a friend to watch the screen in test mode as you spin the pot slowly.
when at 0E reinstall the pot and work on the gear setting.

what you're looking to do is configure the Pot to max out at 0E when
the post of the pedal reaches the end of it's travel at the top of the
cabinent.

if you do all this and the values still are not right then it may be a
bad pot or it was swapped out in error w/ the wrong rating (k).

sometimes when i'm cal'ing my pedel i actually PULL it UP and hold it
while hitting the Weapon Van button to apply the setting. maybe give
that a try.

check the physical pedal too... i know we always thing of the
electrics, pots, roms, volts, amps and such but is your pedal
phsically pushing down all the way to the floor? anything blocking it?

post back. w/ results

"Douglas Paterson" <lastname....@verizon.net> wrote in message news:<GgbZc.276$YP1.267@trnddc03>...

[Mickey Johnson]

no problem

Mickster

"Greg Baumgratz" <rgvac...@galaxian.com> wrote in message

news:2pm7hgF...@uni-berlin.de...

[Greg Baumgratz]

Actually, I grew tired of trying to calibrate the pedal in the cab and
removed the pot to run it through the coin door. Now I can calibrate it
easily and see the screen at the same time. Problem is that the value
stays close to 00 most of the travel and starts to increase toward the
end of the counter clockwise rotation. At the point that it reads '0E'
(if I recall the required value correctly) it is near the end of the
counterclockwise travel. The application of the pedal actually turns
the pot counterclockwise when looking at the pot (with the shaft visible
and pointing at you). At the point the setting is correct for the
calibration, there is only ~1/4 to 1/2 turn avaialable before the pot
rotation ends. This results is only slight acceleration. I have
verified that the pot seems to change value consistantly throughout the
range of adjustment.

Assuming that an increase in voltage results in an increase in speed, I
would assume that the voltage is not rising enough to indicate a higher
speed, but I would need to look into it more.

What I am not sure about is if the steering and pedal values are read
through the same A/D convertor, and the steering seems to be calibrated
correctly, wouldn't this indicate a problem between the A/D convertor
and the pedal? If anyone can explain this one, maybe the answer lies
here. I am concentrating on the absolute position board and not the
SSIO board and maybe I should be looking elsewhere. I need to check the
value of the pot as well to make sure someone didn't replace it with the
wrong one. If I remember correctly, it was a 10K. I need to check
that when I get home. I have another SSIO board that I am working on to
test in the next day or so as well, so I can see if it follows the board
or not.

Thanks,
Greg

[defaul...@yahoo.com]

i'm pretty sure that there is no A/D converter needed or present in SH.
all steering and pedal action is analog already. that's what Pots are
for. it's not getting an on/off [1/0] signal. it's sencing how FAR the
pot has turned. the board is sensing this when the resistence is either
increased or decreased. all a pot really is, is a variable resistor.

[Paul]

Zinferm,

There should be one spring on EACH side of the steering wheel holding
the wheel centered.

If by "one spring" you mean there is only one spring on each side then
that is correct.

You may have additional holes because somebody had added extra springs
to make up for weak originals or moved the springs because the
original holed pulled thru (very common)

D

[Zinfer]

Thanks for the help and confirmation of my belief. No I have two
control panels, one purchased from Ebay, the other came with a
complete project. Both only have one spring on the right side.
Seemed wierd to me as far as getting the wheel to center. I looked it
up in the manual and it still only showed one spring. I was left
scratching my head after that. One area that may be of interest is
trying to find those plastic hole inserts. :)
Oh, and on the pedal calibration. I'd love to help guys but my
monitor's still on the fritz. But when I push the accelerator (of
which I'm missing the actual footpedal) it responds just fine. Not
sure why I'm not having to calibrate anything. It just comes up and
plays. Probably an ignorant post as I'll find out when I get a video
signal/neck glow.

[Greg Baumgratz]

Check your absolute position board for the ic marked ADC0804 - that's
the A/D converter. Digital circuits need them to 'digitize' analog
values and make them easier to compare. For a 4-bit A/D converter the
range may vary as such:

0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111

and this is how it senses a 'range'. In this case it's an 8-bit A/D,
but I am not sure if it is multiplexing the data as two 8 bit signals or
reading it as two 4 bit signals at the same time. Now if I could just
figure out why mine seems to be lacking the range needed to allow for
greater acceleration. As soon as I get the data bus short out of my
second SSIO board I will be able to tell if it is a SSIO problem or
external to the boardset, i.e. pedal, pot, absolute position or wiring.

~Greg

[defaul...@yahoo.com]

That makes sense. Thanks for clearing that up for me Greg.

[Greg Baumgratz]

Just for the sake of posterity, and that there was not much out there
that I could find deling with the absolute position board...

Symptom: Steering calibrates fine with full range of motion. Pedal is
close to the end of the pots travel in order to reach calibrated at rest
value of 'OE'. Only slight acceleration is possible.

One Solution: In my case C1 (.1uF) on the absolute postion board was
shorted to ~250ohm resistance. Replacing this fixed the problem.

~Greg