CompuServe Messages

Marion, It's really difficult to do that because various memory boards likely use different jumper combinations. For instance, on my old Microbotics 8UP board there was only one jumper needed to enable/disable a 2 meg bank. So it was easy to simpy run two wires from the jumper pins to a SPST toggle switch. But on my Nexus there are two jumpers involved, so I had to run 4 wires from the jumper pins to a DPST toggle switch. Thus, the mechanism required is very product dependent, but the concept is basically simple: o———o o o———o/ | jumpwe | SPST switch When the switch is open the jumper is open and when the switch is closed the jumper is shorted. The memory is enabled/disabled depending upon whether the jumper is shorted or opened. If more than one jumper must be controlled, then you either add another switch (the hard way) or get a multi-pole switch. If you need to control two jumpers, then a DPST switch will do the trick with both poles wired the same as above. Of course, this can get complicated if the board requires shorting one jumper while opening another! As you can see there isn't ONE neat solution.