3 Country Switch & Circuit
Next to the Megadrive/Genesis the Saturn is the easiest console to do a country mod for.The country type is simply determinded by a set of jumpers on the board. These are either connected or disconnected depending on the country of origin.
Since the information for making the 3 country/position switch and circuit is what seems to be missing from most other Saturn MOD pages, we'll start with that.
NOTE:JP8 and JP9 are the same for all systems, and should not be altered.
They work in pairs, so only one of the pair is connected at a time.
The even numbered jumpers (6,10,12) are connected to +5.2V (logic 1) and the odd numbered jumpers are connected to ground (logic 0).
So to switch countries all you need to is break the existing
connections on the board and install a switch.
This is simple enough for a 2 country soluttion (Jap/Eur or Jap/USA)
but for a 3 country switch you either need
a)2 or more switches
b)a 3 position switch and a bit of electronics
We're going for option b.
Here's which jumpers are connected for each territory
Going back to our logic 1 or logic 0 for each jumper pair,
these settings translate to.
So all we need do is connected a wire to the mid-point of each jumper pair then set these lines to 1 or 0 appropriatly.
The most obvious solution is to use an OR gate (7432) 3 resistors and 3 position switch.
You then 'OR' the European and American positions and connect the output to JP10/11.
The solution presented here uses a hex inverter instead (7404) which means less components, less soldering ; and the components are easier to find (for me, anyway).