I had some fun with the Adafruit TLV320DAC3100. This is a small board built around the (TLV320)DAC3100 audio chip. “DAC” stands for “Digital-to-Analog Conversion”; that is, it takes some audio signal (here, I²S) and converts it to the analog equivalent (differential for speakers, single-ended for headphones). Microcontrollers typically don’t have analog output, and getting analog […] The post My first PCB: AIC3204 eval board appeared first on Quentin Santos.

A picture is worth a thousand LLM prompts: Horizontal value is the input value x for cosf(x), ranging from 0 to 2π. The orange line shows the result of evaluating cosf(x), which looks exactly as expected. The blue line shows the time it took to evaluate cosf(x) for each x, in nanoseconds. I discovered this […] The post A few spikes in Pico cos() appeared first on Quentin Santos.

I had a few hours of “fun” figuring out why my RP2350 could use my ILI9341 display, but not the ST7796 one. To be more specific, displaying stuff with the first display worked flawlessly, while the ST7796 would display a single frame correctly, and then glitch. Depending on the exact code running, the glitches would […] The post The RP2350 is too fast appeared first on Quentin Santos.

What’s better for New Year’s Eve than debugging some USB hardware issues? In my previous article, I explained how the design of Waveshare’s RP2350-USB-A can make the USB-A host connector incapable of detecting certain USB devices, and of any hot-plugging. The solution was to desolder R13, a pull-up resistor on D+: With this fix, my […] The post The RP2350-USB-A cannot see devices disconnect appeared first on Quentin Santos.

tl;dr: you need to desolder R13, the resistor closest the pin 6 of the board, as indicated by the red arrow in the cover picture of this article Context I am currently toying around with emulating a USB device. However, I also wanted to be able to plug a keyboard in, so I needed a … Continue reading Fixing the RP2350-USB-A not working as USB host → The post Fixing the RP2350-USB-A not working as USB host appeared first on Quentin Santos.