When it does not work
Start from what you can see. Most faults with this kit are one of six, and each has a check that costs seconds and one that costs minutes. Do the cheap one first.
Cheapest check first
Two facts explain most of what goes wrong, so check them before anything else:
- The USB-C socket carries no data. Programs and messages go through the development board's own USB socket.
- The acceptor's 12 V comes only from USB-C. With just the development board's USB in, the buttons work and the acceptor is dead.
Symptoms and where to look
| You see | Look at |
|---|---|
| Nothing prints | Board USB, port, 115200, then the adapter's position |
| A button always pressed | COM and NO on the switch, not NC |
| Joystick directions swapped | Wire by the input monitor, not by position |
| Coin taken, nothing counted | USB-C in, then the coin probe |
| One coin counts as several | Group gap against the acceptor's pulse spacing |
| Screen white | Adapter is not the Nano, ribbon way round, controller matches |
| KEY9, KEY10 dead on a Zero | Serial port off in raspi-config |
Before you ask
Say which adapter and which development board, which example, and paste the exact output. A photo of the header with the adapter in shows a one-position offset at a glance. For a screen, name the controller on the panel; the size does not identify it.
When it does not work
Unplug everything, pull the adapter and look at the header: one position out moves every signal along by one, and puts the mainboard's 5 V onto the board's ground or its 3.3 V pin. Line up GND with GND at the USB-C end and try again.
A lead came off, or a screw is touching the underside of a board. Stand the boards off the case on spacers, keep the coin path clear of the electronics, and run the input monitor and coin probe again before you close it.
Unplug it. Something is shorted, most often a metal screw or offcut under a board, or an adapter one position out. Nothing in a working kit should get warm to the touch.
On the kit's GitHub repository, as an issue: the adapter, the development board, the example, the exact output, and a photo of the header. Questions about using the kit go in the discussion under this page.
The reference page: the pin tables for all four adapters, the specifications and the downloads.
HotSwap Arcade Kit →Edit this page — content/books/arcade/when-it-does-not-work.mdx
Questions about this product
See what other owners have asked, and read their solutions.
HotSwap Arcade Kit: Buttons, Joystick and Coin Acceptor for ESP32-S3, Nano, Pico and Zero 2 W
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