I think you are confusing things a little. you have some kind of controller input device yeah? (like a ipac or something along those lines)
one of those lines will need to be designated the input for coin. you then wire the output of your acceptor to that line.
the problem is, your sr5 is likely (and maybe hopefully) using "parallel mode type 1 output" which has a separate output for each and every coin (8 total)... while this is much faster from a vending standpoint, it's not particularly useful in a videogame credit system like mame since we only have 1 or 2 inputs for coins (usually)
but you can still make it work, you just need to isolate the coin you wish to use.... and the line in which it switches to indicate the coins insertion...and allow that coin.
one of the other types of programming which work better for this type of installation is type 3, which uses a single line for several types of coins such as 1 time for a 5 cent... 2 times for 10 cents, 5 times for 25 cents, and so on and so forth it's slower, but give it greater flexibility.
the second more expensive acceptor I linked is set up this way... you just have to choose your minimum coin value and it pulses in multiples of that coin. so if you wanted for example to accept 0.25, 1.00, and 2.00 coins, you set it up:
0.25 - 1 pulse
1.00 - 4 pulses
2.00 - 8 pulses
in any case, the acceptor needs to be powered with 12v and that's basically it. You can steal power from the black and yellow wires on a computer power supply... or use an external power adapter If you use an external adapter, (power brick/wall wart) be sure to attach the negative power lead of the adapter, to the negative of the computer to tie them together, otherwise when the coin acceptor switches to indicate a coin, the computer can't see it becasue the acceptor switches "low" or the negative voltage. if not shared...can't see it.
for the SR5 and say coin #1...
power (+) - pin 11 (power 12v)
power (-) - pin 12 (also tied to computer negative or chassis)
coin line - pin 4 to ipac coin switch input
connect to power (-) 10,13,14,16,17,18,19
this essentially accepts coin1 (whatever it's programmed as) and rejects all others regardless if it's a programmed coin or not.
but you will have to see what it's currently programmed as to find out what coin line 1 to 8 you want. usually the label on the front has some idea what's in there, but it may have been changed since it was applied.
BUT, this is all for nothing if the acceptor was programmed to speak directly with a machine via cctalk. it does not output coin switches, it communicates the coin status directly through a serial connection to a CPU.