Timeline for Fast SPI reading
Current License: CC BY-SA 4.0
9 events
| when toggle format | what | by | license | comment | |
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| Jan 31, 2022 at 18:02 | comment | added | joan | Your question says the Python is reading 44100 samples in 2 seconds. That is 22k. More than the 15k from your C. | |
| Jan 31, 2022 at 16:55 | comment | added | Pygmalion |
I am using RPi4 and sampling is faster with C. I am using spi.delay_usecs = 0; spi.speed_hz = frequency; spi.bits_per_word = 8;
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| Jan 31, 2022 at 16:49 | comment | added | joan | You are doing something wrong if you are getting slower rates in C compared to Python. Have you set the SPI bit rate in your C code? | |
| Jan 31, 2022 at 16:33 | comment | added | joan | Use pigpio. Use a faster Pi (you appear to be using an old one). | |
| Jan 31, 2022 at 16:15 | comment | added | Pygmalion |
With a simple C script (ioctl(fd_spi, SPI_IOC_MESSAGE(1), &spi); spi.rx_buf = spi.rx_buf + 2;) I could get about 15k sampling. Unfortunately sampling is not very consistent, which means that FFT of the sound is rather noisy. Any ideas for improvement?
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| Jan 31, 2022 at 13:34 | comment | added | Pygmalion |
@Abel I intend to use ctypes since I already have experience with that.
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| Jan 31, 2022 at 12:39 | comment | added | Abel | integrate top level python calls into low level c calls with cython. don't do a big for loop in python- instead loop in c but tell c the number to loop via python. | |
| Jan 31, 2022 at 9:55 | vote | accept | Pygmalion | ||
| Jan 31, 2022 at 9:55 | |||||
| Jan 30, 2022 at 22:37 | history | answered | joan | CC BY-SA 4.0 |