@username123115

audio works!!!

I can convert a clip into 8 bit pcm and play it via pwm on my pi pico. There’s a lot to improve in terms of sound quality but I’ve learned enough to know how to add it to my board. Moving on I want to play with adding a low pass filter to smooth out the PWM signal and using an amplifier.

While writing the software this guide and the accompanying git repo has been very useful for figuring out to use embedded rust. With it I figured out how to use the pico-rs crate which provided some abstractions that made writing the PWM code very easy

previously I tried getting a LED blinking example working on my pico, but the LED wouldn’t turn off which led me to assume my program was crashing before the LED turned off and I spent a bit of time inspecting the executable and debugging my board with the probe.

It turns out nothing crashed, but my delay function which busy waits by executing 12 million nops waits too long, because I used an iterator for my loop. The iterator overhead is much higher then a single nop instruction, so I never got to see my LED toggle.

I’ve got a debug probe connected to my pi pico and started writing some firmware to drive the speaker. Eventually I’ll port it over to the keychain board.

I’ve been curious about writing firmware in rust so I chose to use it for this project. There’s a bit of a learning curve but after a bit of setup I’ve managed to turn on the pico’s on board LED

With the probe I can just run cargo run to build and run on the board, would definitely recommend over using the pico’s BOOTSEL button.

I did some research on the types of speakers I can use for my keychain and found this OWS-091630LA-8B SPEAKER 8OHM 1W TOP PORT 95DB) one on digikey. I haven’t worked with speakers before, so I also disassembled a pair of broken headphones I had lying around and I’m going to spend some time getting my pi pico to play something on it so I know how to wire it up correctly.

I’ve been working on the schematic for a RP2040 based board that I plan on turning into a programmable keychain.

I have some unlogged time spent sourcing a USBC connector and LDO for the system. For this devlog I’ve added a 16mbit flash on digikey that is compatible with the RP2040

Current component list is:

• Clock: ABM8-272-T3 (This is recommended by hardware design guide)
• LDO: NCP186BMX330TAG
• USBC Receptacle: Any 16pin receptacle
• Flash: AT25SF161B-SSHD-B

Also fun fact apparently KiCAD saves history in a .history/ hidden git repo in your project

Finished writing a section on jq and therefore writeup is done! Also recorded a demo video and uploaded to hackclub CDN

script now hides scratch windows by tiling them and having niri place them off screen. Readme has been updated to account for this

I’ve finished writing up working with niri msg, there’s a primer on jq that’s missing that is very important but otherwise most of the useful info is there

I want this to be a writeup/blog post kinda thing where I walk over writing my first niri script. the goal is to include enough info that anyone/me in the future(when I inevitably forget) can get a solid idea/start working with niri ipc. Intro section/overview is done. Script was finished before setting up hackatime but I have a feeling most of my time will be spent on the readme…