Recent content on fdi.sk
After my year-long quest to debug a mysterious and faulty TCP connection, I created go-tcpinfo. It’s a Go library for safely getting TCP_INFO metrics from the Linux kernel, built to provide the deep observability needed to solve such issues.
I remove the unreliable Bluetooth module from my cheap ELM327 (clone) OBD-II scan tool and add good-old wired USB.
The adventure of bringing an early consumer GPS module (23 years old!) to life and connecting it to a Raspberry Pi to make a stratum-1 NTP server. Bonus: some reflections on tech that was built to last.
An experiment with Rust’s embedded-hal abstraction: I have a common implementation of Game Of Life rendering to an OLED display on three different platforms: an SDL simulator on my desktop, and via I2C on Raspberry Pi running Linux, and bare metal on an STM32 ARM Cortex-M.
I tell a story (mostly with photos) about replacing my incorrectly assembled ZMPT101B mains voltage sensor module by replacing an incorrect op-amp after figuring out what the correct part is (through some internet sleuthing).
I work out how to save RD6006 power supply calibration register values (by sniffing serial port output from the RDTech Windows software) and then write two Python scripts: one to adjust the calibration and another to check it by sweeping through the output voltage range, measure and then plot actual output values.
A story about implementing Conway’s Game Of Life while learning the Verilog hardware description language. I do a performance comparison between a hand-implemented C++ version and a simulator generated with the fantastic Verilator. Along the way there is some Python bashing and a minor existential crisis. Fun times!