This project implements a settings recommender for photography. The ISO, shutter speed and focal ratio values are inputed using a rotational encoder and a four-digit seven-segment display. After inputing the values, an external luxmeter is read via SPI interface and all of the values are used to retrieve the recommended setting from a LUT in an SPI Flash. The recommended value is displayed on the four-digit seven-segment display.
This project uses a user interface consisting of a rotational encoder and four-digit seven-segment display. After reset or power-up, first the ISO value is selected by rotating the encoder. The current value is displayed on the four-digit seven-segment display and it is confirmed by a short press on the rotational encoder. Next, the shutter speed is selected by rotating and confirmed by a short press of the encoder. Finally, the focal ratio is selected by rotating the encoder and it is confirmed by a medium press of the encoder. After reading the luxmeter and the flash-based LUT, the recommended settings value is shown on the four-digit seven-segment display.
External hardware comprises of a rotational encoder, a four-digit seven-segment display, SPI luxmeter (e.g. Pmod ALS) and SPI flash (e.g. MX25L3233FMI-08G).
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | A (rot_encoder) | a (seven_seg) | an[0] (seven_seg) |
| 1 | B (rot_encoder) | b (seven_seg) | an[1] (seven_seg) |
| 2 | PB (rot_encoder) | c (seven_seg) | an[2] (seven_seg) |
| 3 | MISO (spi_flash) | d (seven_seg) | an[3] (seven_seg) |
| 4 | MISO (spi_sensor) | e (seven_seg) | SCLK (spi_flash, spi_sensor) |
| 5 | f (seven_seg) | SS (spi_flash) | |
| 6 | g (seven_seg) | SS (spi_sensor) | |
| 7 | dp (seven_seg) | MOSI (spi_flash) |