MicroPython Forum (Archive)

Hi Dave,

Thanks for that ... very interesting, will have a look inti it.

Cheers,
Bernie

Dang, suspected as much. Back to the drawing board.

EDIT: .. maybe a better platform would be measuring the input period directly with a RP3 in assembly .... (very off topic for this forum)

Hi, I was thinking along similar lines. My thoughts where to input the frequency to a digital phase comparator (which is one line of Python code) the other input to the phase comparator is the reference frequency (output freq). The output of the phase comparator goes to a biquad digital filter (in P...

Guess I will have to look at another solution.
I can use a DDS chip from Analog devices for output ... but need to find something else for freq input ...

Cheers,

cross-posted .... thanks for the reply ..

I can't divide down as the PLL has to respond to frequency and phase of both reference and input signals

Hi, I have a similar requirement where I want to periodically measure the freq/width of an input signal. The input signal will vary in frequency between 1 and 10Mhz, and the sampling rate that I do this measurement can be as slow as 10khz .. I presume I could in assembly do a busy wait on an edge, r...

Excellent stuff. Be great if you implemented the callback or soft interrupt on completion ... that would make it perfect.
(I love event driven code ...no waiting ..)

pythoncoder wrote:

I also have a filter that I could easily re-write in assembly

I assume you've seen my FIR filters in assembler https://github.com/peterhinch/micropython-filters.git

Thanks, had not seen those ..

I think @manitou is suggesting that acquiring data at a high rate may be pointless if Python can't subsequently process it at the same rate. Although you might be able to implement a fast decimation filter using the inline assembler to reduce the data rate to a more manageable level. On the subject...

I haven't tried any of this, and such one-off asynchronous solutions would probably require that you hack the firmware. . Yes, I could hack the firmware, but I thought one of the aims of this forum was to give the maintainers of microPython, some feedback on customer use, and if more people want a ...