Below are various useful tips and techniques which do not quite fit in projects.

Execution tracing on Cortex-M microcontrollers

The ARM CoreSight Trace Macrocells are not really a secret, they are publicly documented and found in pretty much every Cortex-M3 and -M4 based microcontroller on the market. However, they seem to be very rarely used — for lack of purpose or for lack of tools?

Giving a cheap diode laser a sharper beam

Cheap 2 EUR line lasers are used for marking the position in tools such as saws and drills. They are also useful for zeroing CNC routers, provided that the line is thin enough to be precise. With a simple trick the line thickness can be reduced while keeping the beam collimated.

Comparison of STM32 series

It was mentioned on ##stm32 @ Freenode that it is difficult to make sense out of the various STM32 families and their comparative prices & features. I decided to make some graphs to help that.

Making 1.5-layer PCBs

I find the alignment of 2-layer boards too cumbersome, and routing 1-layer boards without jumpwires is also difficult. Instead I have found a good compromise that I call 1.5-layer PCBs: only the top layer is etched, while the bottom layer is solid ground plane. This eases routing and improves noise performance while being as easy to make as a 1-layer PCB.

Oogoo tips - or small rubber animals

Oogoo is a recipe for silicone caulk that can be shaped by hand and sets by itself. Basically it's just hardware store silicone mixed with corn starch and oil-based paint.