#trinkey

Trinket 🎀🎀🎀

With recent work to improve our soil moisture sensing, it could be a nice time to design an 'all-in-one' board for plant and garden hacking. This board has a USB C, so you can plug it right into your computer and read the capacitance of the soil, as well as the ambient light level and temperature + humidity of the onboard AHT20. A QT sensor and 'standard Stemma QT' mounting holes mean you can plug in a VOC, CO2, UV, or PM.2 sensor. The SAMD21E18 can run Arduino or CircuitPython, but we'll also ship it with an example that just spits out CSV data over the serial port for instant interfacing. Coming soon.

This is a trinkey with an SHT45 (https://www.adafruit.com/product/5665), a favorite humidity and temperature sensor! The factory code will just spit out temperature and humidity over the USB Serial port in CSV format for easy integration. there's also a neopixel and a captouch sensor. we added a U-shaped cut-out to minimize self-heating from the neopixel or samd21 chip to get the best accuracy, we'll also have a version with an SHT41 that's less expensive (https://www.adafruit.com/product/5776)

These two ESP32 trinkeys look similar, but they're not the same! Yes - both plug into USB A ports, both have reset and user buttons, a NeoPixel and red LED, plus a STEMMA QT I2C port and 3-pin JST SH for analog/digital/PWM. they both contain a CH343P + dual NPN FET for auto-reset circuitry…but one has an ESP32 Pico N8R2 (https://www.digikey.com/short/9ppmnh07) and the other is an ESP32 Mini N4 (https://www.digikey.com/short/31m1drf8). the first module is smaller and contains 8 MB of QSPI flash + 2 MB of PSRAM. The second is larger but only has 4 MB of flash and no PSRAM. why have both? cause the Mini is significantly less expensive, $2.30 vs $3.50, which adds $3 to the final price. For CircuitPython usage, the PSRAM is essential - but for plain C/C++ development, you can get away with skipping. either way, these could be handy little boards for creating sensor nodes that plug into a wall outlet, with easy extensibility for I2C or analog/digital/PWM I/O!

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Having wrapped the feather ESP32-C6 (https://github.com/espressif/arduino-esp32/pull/9961) we think it would be neat to have a USB key 'Trinkey' board for the 'C6 because with WiFi+BLE+ZigBee and USB support, this could act as a low-cost gateway or relay board. We kept it simple here: USB type A in, two buttons for resetting and bootloader-select or user input, one red LED, one NeoPixel, Qwiic/Stemma QT I2C port, and a 3-pin JST SH with gpio #0, which can do PWM/ADC/digital in case you want to add another potentiometer, relay, servo or NeoPixels (on the back you can select if you wish to 3V or 5V power). The goal here is to keep it small, cheap, and extensible. We think we did a good job; what do you think?

We were taking a look at the new Windows 11 HID Dynamic Lighting protocol (https://learn.microsoft.com/en-us/windows-hardware/design/component-guidelines/dynamic-lighting-devices) and i thought this would be a good excuse to design a small NeoPixel or DotStar driver board. like many of our other Trinkeys (https://www.adafruit.com/search?q=Trinkey) it is running a SAM21E18, which is a small chip, but the 32KB of SRAM can drive nearly 10,000 pixels! we put a 5V level shifter on a SPI peripheral so they could be used as data/clock or, if you want, two NeoPixel strands. this isn't a super-fancy driver: it isn't NeoPXL8 (https://www.adafruit.com/search?q=neopxl8) where you get dithering and DMA, but it's probably just fine for the vast amount of lighting projects.

This is a trinkey with an SHT45, a favorite humidity and temperature sensor! The factory code will just spit out temperature and humidity over the USB Serial port in CSV format for easy integration. there's also a neopixel and a captouch sensor. the samd21e18 is fairly low power and as long as the NeoPixel isnt on full blast we don't think there'll be a lot of self-heating. lots more Trinkey's coming down the pipe! any suggestions you have for other Trinkeys you want us to design?