picoDarkroomTimer is a digital darkroom measurement device and timer. It`s powered by a Raspberry Pi Pico microcontroller, a 2.8" SPI LCD (320x240 px), an encoder knob, 5 buttons and a beeper. Configuration values can be stored in a serial EEPROM.
Darkroom light and Enlarger are controlled via an attached PCB with two relays and the power supply.
Light measurements are done with an Adafruit_TSL2591 sensor module, offering a very wide sensitivity range and true visible light measurements in Lux values.
The current software can work as a digital timer (0...99s) or a measurement device, that measures shadow point and light point, calculates the tonal range, recommends a (multigrade) paper grade and calculates resulting exposure time (after calibrating the paper sensitivity). The resulting time can be corrected in steps of 1/3 f.
the 5 buttons (plus external sensor button) can be programmed individually. There is a version with two buttons combined for a wide start button keycap. Buttons are real typewriter buttons with haptic feedback (gateron / redragon) - true old school.
The case and powerbrick are available as SLA 3D printed parts.
You can program your own stuff on the device.