Rapid Fire Circuit

[Ambrocade]

My fingers just can't take beating on buttons all the time.  

I can work a soldering iron but unfortunately I don't understand gates and 555 timers and therefore don't know how to design a rapid fire circuit.

Anyone have a circuit design they would be willing to share?

It appears there used to be one on the Closet2Mame site but the link I have doesn't work.

Any help would be appreciated.

[1UP]

Radio Shack has cheap little books with sample circuits for this purpose (usually made to flash LEDs etc).

Also try this site: http://webhome.idirect.com/~jadams/electronics/

I had a circuit I was going to use for my T2 guns before I got the recoil to work correctly.  I'll post it if I come across it.

[Dav]

I made one for a friend once, it was similar to this one that I just found in google.

http://www.westminster.org.uk/intranet/departments/electronics/555.htm#pins

I ran the output into a 4066 switch and spliced the 4066 into the line to the switch.  Iirc I used 2 10k pots for r1,r2 and 100uf for c because I had them laying around.

I'm thinking about running off a few of them when I make my next order of circuit  boards.

Dave

[Druin]

I have also another circuit that can do rapid fire.  It doesn't use the calculation-intensive 555 timer, and looks easier to handle.  

http://members.rogers.com/druins22/arcade/

Click on the rapid fire link...it is just the oscillator to generate the pulses.  To make it interface with the switches you'd do as someone else said, use it to control a 4066 chip.  There is a 4066 circuit on this site as well, set up to show how to use one switch to control 3 switches at the same time...the rapid fire circuit can be hooked up to that. I can explain more if this circuit is going to be experimented with.

[1-up]

I was thinking you could just use a simple resitor-capacitor LED flasher to do the trick.  Add a push-on/push-off switch to toggle it, sub a pot for the resistor, and you'd have an adjustable turbo switch, no?

[enemyace]

Isn't there some way to do it in software?

[1UP]

Isn't there some way to do it in software?

The problem is, there is software PREVENTING rapid fire.

[Ambrocade]

Thanks a lot guys for the links and ideas.  I haven't looked at them yet but definitely plan on doing so.

Thanks again!

[JMDickson]

The problem is, there is software PREVENTING rapid fire.  If you go into notepad (or any Windows app) and hold down 'A', you get a string of aaaaaaaaaaaaaa until you let go.  Mame apparently translates this into the button being held down, rather than the button repeating.  If there's a feature in Mame that lets you bypass this for certain keys, I don't know about it.  Anyone?

Not exactly...
 What you are seeing in notepad is called typematic.  It is a function of the bios/os placing keystrokes into the keystroke buffer when the key is held down.  MAME does not use the buffer, but instead reads the actual state of the key based on key make/break messages.