MQTT Stopwatch / Display

MQTT Stopwatch / Display

Parts to Buy (MQTT Stopwatch / Display)

Qty Name Notes
1 MatrixPortal Board
2 64x32 LED Matrix 4mm pitch
1 power supply / cable USB-C end, 5v, 4A

Adafruit publishes an excellent guide that describes how to setup and use the MatrixPortal.

Optional Purchased Parts

Qty Name Notes
2 Acrylic Diffuser
1 Adhesive Squares (6-pack)
- Magnetic Feet(4-pack)
- Power Wires

These diffusers are optional, but they make the display more attractive. Also, if you plan on photographing the display, they reduce the brightness enough that the colors don't wash out in the photo or video. These are pre-cut to match the size of the 32x64 4mm-pitch displays. The adhesive squares may be used to affix the diffusers to the display panels -- they would look nicer than the duct tape i used in mine...

The magnetic feet are handy if you want to affix the panel to a metalic surface; if you prefer to hang it (ie, by suction cups or hooks), consider 3d-printing some hangers.

The Power Wires are only needed if you extend this beyond 2 matrix panels. The MatrixPortal comes with one set of wires, which can drive 2 panels. If you extend, you'll need one of these for each additional 2 panels, and you'll need to do a little bit of surgery to make it work.

Alternative Matrix Sizes

Pitch Size Purchase Link
3mm 191 x 96 mm
4mm 255 x 127 mm
5mm 318 x 158 mm
6mm 385 x 190 mm
300x300 Uncut Diffuser

The 4mm-pitch panels described in the first section above are 255x127 mm in size, leading to a total display size of 510x127mm. You can alternatively purchase 3mm or 6mm pitch panels as listed here to vary the final size of the display. If you do that, the pre-cut acrylic panels won't fit those displays but you can purchase larger acrylic panels and cut them yourself (or go without them...). Regardless of panel size, the same MatrixPortal board is used.