Hackerboxes 0028 - Jambox Part 1

Hackerbox 0028 Jambox is all about digital audio and the esp32. The custom pcb included provisions for a gang of 4 8x8 SPI driven led grids, 5 10K pots and 8 push buttons. It also has a provision for an esp32 and a Burr-Brown (now TI) DAC, the PCM5012A.

The esp32 has several ADC and two DAC channels. There are a number of projects that the i'ble links to such as:

Using the esp32 and built in storage and DAC to generate 8bit analog out at line level:

Using the esp32 with either a built in DAC or an external I2S DAC (PCM5012A) to play music from an external SPI connected SD card:

They provide an example sequencer project that uses the esp32 to generate "tones" and play them back, but for me that project has a weakness in that it does not produce pure tones. I struggled a bit with the examples from Espressif and discovered that one way to produce pure tones you to completley fill the DMA buffers with an even number of cycles of your desired frequency:

So in an upcoming video I will explain a bit more about what that means and hopefully find a way to generate tones that can be adjusted using some user input.