How does it work
On the Amiga 500,500+,2000,3000 you can’t boot from the external (DF1) drive by default, so you need a switch so the external (DF1) drive will act as DF0:
Switch position 1 (default)
- Internal Drive is DF0:
- External Drive is DF1:
Switch position 2
- External Drive will be acting as DF0:
- Internal Drive will be disabled.
Technically it will swap _SEL0 & _SEL1.
What do you need
1x 40 pin normal/default socket
2x 40 pin machined/precision sockets
1x 6 pin toggle switch
How to build it
Socket 1 (normal socket)
- First we take the normal 40 pin socket, and we bend pin 13 & 14 90 degrees to the outside.
- Solder two wires to pin 13 (red) & 14 (yellow)
Socket 2 (precision socket)
- Take one of the precision sockets, and solder 2 wires to pin 13 (green) & 14 (white)
Socket 3 (precision socket)
- Take the second precision socket and remove pin 13 & 14
Put the sockets together
Stack the sockets like this:
- Socket 1, standard socket with red & yellow wire
- Socket 2, precision socket with the removed pins
- Socket 3, precision socket with the green & white wire
Add the switch
Solder the wires to the according pins of the switch
- Pin 1: Red
- Pin 2: Yellow
- pin 3: Green
- pin 4: White
- Pin 5: crossover wire from pin 2 (yellow)
- Pin 6: crossover wire from pin 1 (red)
Install into Amiga 500
Proceed at your own risk! I’m not responsible for any damage to you board! I’m not responsible for mistakes you made in assembling the drive selector.
Please note that the notches of the sockets and chips are all facing into the same (good) direction!
- Remove CIA (U8) carefully
- Place the assembled socket stack into the socket U8
- Place the CIA on top of the socket stack
- Please test the selector before putting a hole into your Amiga!