Following on from Making your own ArduinoBoy, here is a photographic guide…
Galley of components
All components (LEDs and header pins are missing – see below)
MIDI connectors. Both PCB mounted and alternative case mounted DIN sockets
Game Link cable, GameLink breakout PCB from OSH Park and GBA GameLink connector
and GameLink breakout PCB from OSH Park and GBA GameLink connector
ICs – optocoupler and microcontroller
The ATmega328P-PU microcontroller
The 6N138 optocouple
The discrete components. 22 pF ceramic capacitors, 8 MHz crystal, 7 x 2.2 kΩ resistors and other resistors of various values (2 x 220 Ω, 1 x 270 Ω, 1 x 4.7 kΩ). Note the alternate diodes on the left (1N4148 (preferred) and 1N4001 respectively)…
The 5 mm LEDs, although 3 mm LEDs can also be used. The yellow LED is used for the status indicator on pin 13.
Looking at the PCB Silk screen (original image)
This is all quite straightforward, just populate the board in the following order:
Note the orientation of the diode, with the cathode (denoted by the black stripe) to the top.
Note that the LEDs have the anode (
+ longer leg) nearer the center of the board, the cathode (
- shorter leg) on the outside of the board
Also, as an added check, the flat side of the LED is next to the edge of the PCB.
The yellow status LED is on the left most LED.
You don’t need all of the various colours but it helps:
- Red – +5V
- Black – GND
- Blue – input
- Yellow – output
- Green – GameLink
- White – Button
After uploading the code to the ATmega328P-PU, via an Arduino Uno (or whatever your preferred method is), then insert into the IC into the board:
Finishing off – External connections
- The white headers are connected to a push button
- The blue headers to the input MIDI DIN
- The yellow headers to the output MIDI DIN
- The green headers to the GameLink connector
- The red and black header pins to 5V and GND respectively.
There is a slight confusion in Trash80’s cartoon schematic, with respect to the MIDI connectors, as the pin of the DIN connector are not labelled. It is not clear whether the MIDI connectors are depicted looking from the front or the rear of the DIN sockets and the representation is not consistent for both DIN sockets.
Looking at a more explicitly annotated photograph
- The left most blue pin header goes to pin 4 – This is connected to the cathode of the 1N4148 diode via the 220 Ω resistor.
- The right most blue pin header goes to pin 5 – This is connected to the anode of the 1N4148 diode.
This is the opposite to that shown in Trash80’s schematic- although it is correct if you assume that you are looking at the front of the socket shown in Trash80’s schematic.
- The middle yellow pin header goes to pin 4 – This is +V via the 220 Ω resistor.
- The left most yellow pin header goes to pin 2 – this is ground.
- The right most yellow pin header goes to pin 5 – this is connected to the Tx on pin 3 of the ATmega328.
Again, this is the opposite to that shown in Trash80’s schematic – although correct if you assume that you are looking at the rear of the socket shown in Trash80’s schematic.
From the top,
the order of the green header pins is:
- BR – GND
- BL – SOUT
- TC – SIN
- TR – SCLK
- TL – +V
Using a standard GameLink PCB connector
or using the Gameboy link from OSH Park:
Using an OMROM push button to reset