Using ARM’s CMSIS DSP Library: arm_sqrt_q15

I continue the ARM CMSIS DSP series, this time demonstrating arm_sqrt_q15. This function takes the sqrt of a fractional input, and returns the value (by reference) and some error detection. Here is the function definition: “in” really is a Q Format of 1.15. 0 is represented as 0x0000. 1 is represented as 0x7FFF. This means Read more about Using ARM’s CMSIS DSP Library: arm_sqrt_q15[…]

Using ARM’s CMSIS DSP Library: arm_recip_q15

I’ve begun using ARM’s free CMSIS DSP library on a project, but the documentation is quite sparse. So, I’ve started documenting how to use these functions as I learn by trial and error. The first function is: arm_recipt_q15. This function takes the reciprocal of a fixed point variable, in. The format of the input, in, Read more about Using ARM’s CMSIS DSP Library: arm_recip_q15[…]