This is the cause....

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Posted by Andy Warne on 6, 2000 at 9:50 AM:

In Reply to: KE72 and Happ coin door help. I'm stumped! posted by JP4 on 5, 2000 at 12:33 PM:

Hi,

The reason this happens is not MAME, nor the Allegro keyboard engine nor the encoder. It's the game ROM.
The game ROM code usually has a timer built in to give a timimg window which verifies the coin pulse is within certain limits. The way it works varies from game to game. For example Galaxian only registers the coin pulse after the coin input goes "low" (ie button released) and it ignores the pulse if it is too short. Some won't register if the pulse is too long.
Now you'd think that using a coin door would make the pulse the same length as the original game machine The problem is because the length of the pulse is being changed by the fact we're emulating rather than running the real ROMs and also because some of the game boards had capacitors across the coin input which lengthened the pulse.
So is there a way round this? Putting a capacitor across the coin micro-switch might do it but it would need some experimentation to get the right value so that the coin pulse is within the right limits.

Andy

: I'm stumped on this one, so if anyone could shed some light on the subject, I'd appreciate it!

: I have the switches on my coin door wired up to pins 40 and 41 on my KE72. I also have a "coin button" (mapped to the "5" keystroke) on the front of my control panel which is wired up to pin 39 on the KE72.

: Here's my problem: When I'm in MAME, dropping a coin into the coin door does absolutely nothing...no credit is registered. If I tap the "coin button" that I have on the front, it *will* register a credit.

: The keys ARE mapped correctly. If I'm in Notepad, DOS, KeyHook, etc., dropping a coin into the door immediately brings up either a "5" or a "6". It's just in MAME that it does nothing.

: I've tried using DOS MAME 0.36 and 0.31 (and the same thing happens whether I use AAH or if I just start from a DOS prompt and type it in) and MAME32 0.36.

: Arrrrgh! Any thoughts? Thanks!

: -JP4
: MAME32 0.36

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Re: This is the cause.... - A possible Solution RoarCade 11/06/2000 (2)
- Re: This is the cause.... - A possible Solution Druin 11/06/2000 (1)
  - It doesn't hurt to ask... PLUS a fix for your toggle question RoarCade 11/06/2000 (0)

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: Hi, : The reason this happens is not MAME, nor the Allegro keyboard engine nor the encoder. It's the game ROM. : The game ROM code usually has a timer built in to give a timimg window which verifies the coin pulse is within certain limits. The way it works varies from game to game. For example Galaxian only registers the coin pulse after the coin input goes "low" (ie button released) and it ignores the pulse if it is too short. Some won't register if the pulse is too long. : Now you'd think that using a coin door would make the pulse the same length as the original game machine The problem is because the length of the pulse is being changed by the fact we're emulating rather than running the real ROMs and also because some of the game boards had capacitors across the coin input which lengthened the pulse. : So is there a way round this? Putting a capacitor across the coin micro-switch might do it but it would need some experimentation to get the right value so that the coin pulse is within the right limits. : Andy : : I'm stumped on this one, so if anyone could shed some light on the subject, I'd appreciate it! : : I have the switches on my coin door wired up to pins 40 and 41 on my KE72. I also have a "coin button" (mapped to the "5" keystroke) on the front of my control panel which is wired up to pin 39 on the KE72. : : Here's my problem: When I'm in MAME, dropping a coin into the coin door does absolutely nothing...no credit is registered. If I tap the "coin button" that I have on the front, it *will* register a credit. : : The keys ARE mapped correctly. If I'm in Notepad, DOS, KeyHook, etc., dropping a coin into the door immediately brings up either a "5" or a "6". It's just in MAME that it does nothing. : : I've tried using DOS MAME 0.36 and 0.31 (and the same thing happens whether I use AAH or if I just start from a DOS prompt and type it in) and MAME32 0.36. : : Arrrrgh! Any thoughts? Thanks! : : -JP4 : : MAME32 0.36

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