Creating a Circuit Board from Scratch

I've been dabbling with creating my own circuit boards for a while now. I recently used KiCad to design this audio DAC circuit board. I had the board manufactured by OSHPark and assembled it myself using a solder paste stencil and my DIY solder reflow oven.

CS4334 Audio DAC Breakout Board

The board plays audio using a typical 3…

Date: July 11th, 2021 at 10:24am
Author: Terence Darwen
Tags: Embedded, Audio, DAC, Cirrus Logic, CS4334, PCB, circuit board, KiCad, I2S, STM32, STM32F4, STM32F411, Audio Software

BLE Wireless Heart Rate Collector

Wanting to learn more about creating embedded Bluetooth Low Energy (BLE) firmware, I recently purchased a Nordic nRF52840 dev kit shown below.

Nordic nRF52840 DK Development Kit

I also purchased an inexpensive BLE heart rate monitor and a small OLED display from Adafruit to use with the nRF52840 to display realtime data from the hea…

Date: August 31st, 2019 at 4:24pm
Author: Terence Darwen
Tags: Embedded, BLE, Bluetooth Low Energy, Heart Rate Collector, Heart Rate Monitor, Nordic, nRF52840-DK, ARM Cortex-M4, SSD1306

In Depth Analysis of an ARM Cortex-M4 Program

I’ve been working with ARM Cortex-M4 microprocessors for a little over a year and a half now. Despite reading popular embedded books and blogs, I have yet to come across an end-to-end overview of the creation and execution of a program.

STM32F4 Chip

For my own education and reference I’ve created such a docume…

Date: January 24th, 2018 at 5:40pm
Author: Terence Darwen
Tags: Embedded, ARM-Cortex-M4, STM32, STM32F4

STM32 Gyroscope / Accelerometer Demo (Video Included)

A number of the STM32 development boards come equipped with a MEMS gyroscope and accelerometer. As shown in the video below, I've written software which displays values from both of these devices in realtime.


In my example, I'm using an STM32F411 development board. As shown on the databri

Date: December 3rd, 2017 at 6:37pm
Author: Terence Darwen
Tags: Embedded, STM32, STM32F4, ARM-Cortex-M4, STM32F411, Gyroscope, Accelerometer

Various STM32 Projects

I've been working on a number of smaller STM32 projects to get to know the processsor and peripherals better. These include UART communication, DMA, configuring various interrupts, clock speeds and more.

STM32F411 Discovery Board

These projects can be found in my GitHub repo. They're well commented to explain what the c…

Date: November 17th, 2017 at 6:53pm
Author: Terence Darwen
Tags: Embedded, STM32, STM32F4, ARM-Cortex-M4, STM32F411