Some people are asking me why didn't I use I-PAC
Well, from the start there were some "special" things I wanted to do, that I-PAC couldn't provide. I had to build a separate controller for all the other "stuff". My thinking was, why to use two different controllers for the machine and not just one?
By using one controller I could also save a lot of money. If you consider that I spend about 130 euros (165 dollars) for all the components (excluding only the front glass that I haven't bought yet) and I-pac costs (on ebay) about 39 dollars without shipping (for my country total cost is about 75 dollars), then its a lot of money (more than one third of total price)
What are the "special" things I am talking about?
Well, here are some of them
This was what I wanted for the power up procedure:
a) When the machine is in standby mode, the television and speakers must be completely turned off (lower power consuption). Only the PC will be in standby mode (PSU and mobo)
b) The machine will start with only one button (the ignition key)
By turning the ignition key the controller powers up the PC (like when you press the power button of the PC)
Then, a relay closes and powers up the speakers and the television, by upplying the 230 Volts (or 110V) to the power cords (of course the power switches are always on)
Some televisions start when you plug them, but others go in standby mode (like mine). In this case you must press the channel up/down button in the TV's front panel. Well, this is what my controller does and succesfully powers up the TV (and all the other components)
For the coin acceptor
I am using a coin acceptor like this one (KAI 638):
http://www.ebay.com/itm/CH-Electronic-CPU-Coin-Selector-coin-Acceptor-sorter-/250795594138?pt=LH_DefaultDomain_0&hash=item3a6495119aIt works with 12Volt power supply, but you can switch the output to open collector state.
This is very important for me, because I can directly connect the output of the coin acceptor to the game controller, with only one pullup resistor
The same thing you must do, if you want to connect it with i-pac.
I don't think its possible to directly connect it (you will also need the pullup resistor), because I think i-pac works with a 5volt power supply (driven from the usb or the ps/2 port).But this is not the important thing.
Imagine you start the machine and windows have not yet started (so mame is not loaded yet). If your coin acceptor is directly powered from your PC's PSU then it will be functional even before MAME is loaded. If you accidentally insert a coin then you will "loose" it, because it will not give you a credit (MAME has not load yet)
The same thing will happen when you are in the frontEnd and you are selecting games. By inserting a valid coin, you will have no credits and you will "loose" the coin
In my case, the controller is powering up the coin acceptor only if a game is loaded. In every other state, power is off and when you insert a coin you will get it back, by pulling down the special handle of the coin acceptor