Тема: gameport
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AK> Хотелось бы сделать датчик темпеpатуpы на основе теpмоpезистоpов и
AK> субжа. Собственно вопpос к каким контактам подключать pезюки, и как
AK> потом считать данные из этого поpта.
15-pin D-shell connector:
PIN SIGNAL PIN SIGNAL
--- ------ --- ------
1 +5V 8 +5V
2 button 1 9 +5V
3 stick 1 10 button 3
4 GND 11 stick 3
5 GND 12 GND
6 stick 2 13 stick 4
7 button 2 14 button 4
15 +5V
Game card has a female connector;
Joystick cable has male connector.
Joystick wiring:
+5 ________________
|
stick1 ________ |
| 100K |
_/\/\/\_____|
stick2 ________ |
| 100K |
_/\/\/\_____|
stick3 ________ |
| 100K |
_/\/\/\_____|
stick4 ________ |
| 100K |
_/\/\/\_____|
___
button1 ______o o_______
___ |
button2 ______o o_______|
___ |
button3 ______o o_______|
___ |
button4 ______o o_______|
|
GND ________________|
> 2) As near as I can figure, I have to use the inpw() function (I'm using
> C) to read the ports. Unfortunately, I don't know the port number to
> give the function to read the port. If this isn't the right/best
> way,
> please let me know.
You need to do byte I/O to and from port 201h.
To read the joysticks (or your slide pot positions), you
must first write a byte to port 201h. It doesn't matter
what value you send, as long as you perform an I/O write.
This triggers the 558 timer on the game adapter.
Game port 201h byte:
_______________________________________________________
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| but4 | but3 | but2 | but1 | stk4 | stk3 | stk2 | stk1 |
|______|______|______|______|______|______|______|______|
The most machine-independent way to sample the game port
is to use a timer. Note the time (e.g., read the countdown
register in Timer 0, you need pretty fine resolution and this
timer performs 65535 counts every 55 ms) just before you
trigger the 558. After triggering, sit in a loop reading
port 201h and examining bits 0-3. For those bits that have
a joystick pot attached, you'll see them sit for a while at 0,
then become 1. As each bit flips back to 1, note the time
again. When all bit 0-3 have flipped back to 1, you're almost
done. Compute elapsed time for each bit, and you end up with
a value that is proportional to pot position.
If you're lazy and don't care about machine independence,
you can just trigger the card, then sit in a loop and count
up from zero. As each bit flips back to 1, save the count
for that bit. I've seen a few games that probably use
this method. Problem is that if you then run the same code
on a faster/slower machine, your calibration can get very
easily messed up.
Buttons can be read at any time just by reading port 201h
and looking at bits 4-7. No triggering is required.
Button bits are normally 1; while a button is depressed,
its bit will flip to 0.
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- [0] SU.HARDW.SCHEMES (2:5025/35.3) ------------------------ SU.HARDW.SCHEMES -
Msg : 303 of 400
From : Evgeny Sitnikov 2:5055/61 23 Feb 97 09:42:28
To : Andy Shevchenko 24 Feb 97 08:08:42
Subj : Внимание всем!
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Здравствуйте, Andy!
Дело было Wednesday February 19 1997 21:04, и Andy Shevchenko писал Evgeny
Sitnikov:
AC>>>> P.S. Я уже давно пользуюсь 5В, выведенными с клавиатуpы.
DZ>>> Кстати, еще на джойстике, вроде, есть.
>> 1 4 5 8 Вид с моpды.
>> * * * * * * * * 4,5 - Gnd
>> * * * * * * * 15,8 - +5V
>> 9 15
AS> И еще 12 - GND.
12 - MIDI Out
9 - MIDI In
AS> С уважением Andy Shevchenko :+)
С уважением, islander.
Sometimes I feel like... Screaming close my eyes, It's times like this
my head goes down and the only thing I know is the name of this town (dp)
... HardRock Group ISLAND Let's Rock!
--- R'n'R not dead, only many it not needed, but some can't live without it...
* Origin: iSLAND Records Studio (Beer'em All) (2:5055/61)
