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8 years, 1 month ago.
LPC4088 QSB Generating a prcise 48 khz square signal ?
I would like to test my LPX4088 as an audio wordclock generator.
To do this I only need to generate an sqare signal of an frequency of 48 khz precisely.
I try with ticker with an value of 10.416667 mircoseconds, it does not seems to be enough precise.
Is there someone that could give me a direction of how to realize it ?
Best regards.
Raph
1 Answer
8 years, 1 month ago.
Ticker rounds to microseconds, so it can't make fractions of it. Same for PWM period. I believe FastPWM supports the LPC4088 too, that gives you full accuracy of what your hardware can do. (In general PWM is better than software for this). It is supposed to run at 120MHz, then it can make exactly 48kHz.
Hmmm indeed, I thought someone once added it. You can try in the LPC1768 code there removing the ifdefs (or add the LPC4088 to it). The LPC1768 and LPC4088 are quite similar, but no guarantees. I don't have the board myself so can't test it.
posted by 19 Mar 2016after few researches it seems that this it is possible just by using spi at the right frequency or easier using i2s as master clock and then generating a perfect 48khz trough this i2s interface with the ws clock. I could also generate an 96khz signal without trouble. could some one says ok about that ?
best regards
posted by 20 Jul 2016