Posted by Reg on 1, 2002 at 7:31 AM:
In Reply to: Re: Big News...NES Light Gun Tests Results... posted by Howard Casto on 1, 2002 at 12:34 AM:
: That's great, but the question is, have you tried the amplified signal in mame yet?
Reg->No, but a program to test the joystick show me that the Switch 4 of joystick is pressed in synch with what I see with the oscilloscope when the gun is pointed on a white target.
I know you haven't wired up the trigger yet, but could'nt you simply hit the fire key on the keyboard and aim the gun for the time being?
Reg->Yes and no The trigger can be connected to activate switch1 of Joystick1 (Mame recognize switch1) but Mame emulate the gun and does not recognize the switch4..
So even if I trig switch4 with an Exidy game in Mame...Mame does not recognize switch4... The driver Exidy driver need to be modified to accept an input from switch4 and there is some tweaking need to insert the right program code at the right place so Mame can activate the proper bit
when the gun see the target... so there are a bit of programming to do in the driver but 80% of the job is already emulated in Mame.
Reg-> I will need to look much further the Exidy driver...The driver name is Exidy440.c
(C:\mingw\mame\src\drivers) and also
(C:\mingw\mame\src\vidhrdw\Exidy440.c)
Or do the exidy drivers not automatically reset the position when you hit fire?
Bye Reg
:
: : Hi,
: : Here are the results of my tests with a NES Light Gun
: : tested with an an oscilloscope:
: : P.s I'am new to use an Oscilloscope...
: :
: : 1. If you cut the wire of a Nes gun you will see the
: : following wires (White "+5V", Brown "Ground",
: : Blue "Gun out", Purple "Gun trigger").
: : 2. To give power to the NES gun and few electronics,
: : you need to hool up the gun to these Joystick pins
: : (Pin 1 "+5V", Pin 4 "ground for button 1")
: : 3. The Gun have been tested with a regular 27 inch
: : Color TV.
: : 4. The Gun can see a white spot small as a "Dime"
: : at 4 feets (may be less than a dime like the size
: : of a pen eraser "the ones made of woods").
: : 5. The Blue wire of the gun have the following signal
: : (if the gun is pointed to a white picture:
: :
: : /| /|
: : / | / | +30 mili volts
: : -----/ | -------------/ | --- ...
: : | / | /
: : | / | / -30 mili volts
: : |/ |/: :
: : | | ----> 1 micro seconds approximatively: :
: : | | ----> 18 micro seconds: : I have overlapped a 60 herts signal over it and it
: : and the signal is also 18 micro seconds.
: :: : 6. I have amplified the signal with two PNP 2N3906
: : and the signal have now this shape:: : -----| |---------------| |-- ...
: : | | | |
: : | | | | .5 volts
: : |______| |______|: :
: : | | ----> 1 micro seconds approximatively: :
: : | | ----> 18 micro seconds: :
: : 7. The idea is to trigger the Switch 4 of the
: : Joystick 1 homemame circuit that I have created do
: : the following:: : amplifiy the signal of the gun, clean it and
: : trig the switch4 of joystick 1,
: : will be distributed soon...): : 8. Why joystick 1 and switch 4, see below
: : (previous post): :
: : First here is a list of games that support Guns:: :
: : Night Stocker (nstocker) Bally/Sente: : Cheyenne V.1.0 (cheyenne) Exidy
: : Chiller V.3.0 (chiller) Exidy
: : Clay Pigeon V.2.0 (Claypign) Exidy
: : Combat V.3.0 (combat) Exidy
: : Crack Shoot V.2.0 (cracksht) Exidy
: : CrossBow V.2.0 (crossbow) Exidy
: : Hit'n miss V.3.0 (hitnmiss) Exidy
: : Hit'n Miss V.2.0 (hitnmis2) Exidy
: : Showdown V.3.0 (showdown) Exidy
: : Who Dunit V.8.0 (whodunit) Exidy: : Terminator2 JudgmentDay (term2) Midway
: : PChoice-10:Duck Hunt (pc_duckh) Nintendo
: : PChoice-10:Hogan's Alley(pc_hglaly) Nintendo
: : PChoice-10: Wild Gunmen (pc_wgnmn) Nintendo: : Turkey Shoot (tshoot) Williams
: : I have seen most pictures of these cabinets and
: : most of them have their gun fixed on the cabinet.
: : That mean that to move the crosspointer on a target,
: : the gun is acting like a big joystick...: : For the trigger Mame already support the Joystick
: : button 1 of Player 1,so clicking this button is the
: : same as using the trigger of the gun.: : The optics are emulated but not ready to be used as
: : is, in Mame without modifying the drivers (like
: : Exidy440.c) by example...: : But If someone buy at Ebay a T2 gun by example Mame
: : will support it if we hack it with a old joystick for
: : the crosshair positionning and use the button 1 of the
: : joystick for the gun trigger...: : Mame will work great without the optics...
: : Just try a regular joystick to play T2 ot Clay Pigeon
: : and you will see...: : If we really want the optics to be implemented, we
: : must amplify the output of a Nes Light gun to trigger
: : a relay like the one implemented in a CMOS 4066 and
: : then trigger button 4 of player 1 of joystick port...: : Why Button 4, because buttons 1,2,3 are used by the
: : games list previously...: :
: : A light gun is sensing light all the time...: : when the trigger is activated it send a signal to the
: : PC to reset their counter and to display a black frame
: : with a small white cursor that moves, when the gun
: : see the cursor it send a signal to the PC to stop the
: : counter and this way the computer know by calculation
: : where the gun was pointed...: : So button 4 can be use to tell the computer to
: : determine if there was a miss or a hit...: : by modifying the Exidy driver most guns games in Mame
: : will work ..: : and apply the same process for Midway, Nintendo and
: : Williams...: :
: : 9. In conclusion, I think the gun can be attached
: : on a homemade base for most games...
: : be detached for games like may be
: : Duck Hunt of PChoice-10.: : 10. Exidy already implement most of the process to
: : make the optics of a light Gun to work..: : Some modifications to the Exidy driver need to
: : be done to recognize the switch 4 of Joystick 1
: : so Mame can know when the gun see a white cursor.: : Some calculations are already implemented...
: : in the Exidy driver...some work need to be done
: : to match the real gun and the emulated one...: : bye
: : Reg