Binary, do you use Hard-Float or Soft-Float?

Many cost-sensitive ARM Cortex-M devices like the M0+ do not have a hardware floating point unit, and some like the M4 only has an optional single-precision floating point unit (FPU). As outlined in “Be aware: Floating Point Operations on ARM Cortex-M4F“, using floating point operations without a hardware unit can be costly.

Looking at the disassembly for sure will tell you if the hardware is handling the float or double operation or not:

Disassembly showing runtime routines

But who wants check the all the disassembly? With the GNU tools there is an easier way: readelf.

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CNC + Laser = Personalized Cutting Board

This blog usually features Printed Circuit Boards (PCBs), but my other passion are Personalized Cutting Boards :-).

It has been a while since my last CNC or laser cutter post, so I thought I showcase just quickly one of the recent designs.

Personalized Cutting Board
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Versatile OSHW Mini MCU-Link Debug Probe: External, On-Board, or Embedded

Who needs a debug probe, if you have printf()? If doing serious development, you most likely want a hardware debug probe. We at the HSLU IET use different hardware, boards and kits, and for many of the classroom equipment it is very useful to have the debug probe embedded on the target board: less cables, easier to use. For this we have developed a new Open Source Hardware (OSHW) debug probe in KiCad which can used in different ways: as external debug probe, integrated and soldered on top of the target board, or fully integrated and embedded into a custom design.

OSHW Mini MCU-Link Debug Probe
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