I am interested in STM32U5 because of CORDIC as I do have trigonometrically intense applications. Apparently DSP with hardware multiply is superior, and is also provided in the STM32U5. Respectfully, why include CORDIC when DSP is also available?

[KnarfB]

DSP is part of the ARM Cortex core instruction set. These are mainly SIMD (vector) instructions and instructions with saturation often based on combinations of add/sub and mul.

CORDIC is a hardware accelerator for speeding-up trigonometric and hyperbolic functions including logarithms. So they both complement each other.

Side note: my first contact with the CORDIC principle was with my HP-41 scientific calculator in the early 80ies 🙂

hth

KnarfB

[Bassett.David]

The CORDIC operations are faster than a sequence of instructions, but of limited precision. You can also overlap a few instructions while the unit is busy.

[S.Ma]

In most cases, fixed point uses normal register which enables faster computation within and interrupt. Using more math registers from fpu or else will require potential longer latencies to push/pop them even in lazy mode. And interrupt duration is affecting the max RPM of a motor, for example.