I want to use the MSGEQ7 in a 21 band spectrum analyzer display. I have seen it done here - https://www.youtube.com/watch?v=ia_uFSg-6-0&t=333s
What I need and cannot find is a frequency setting for frequency 2. This is for the Si5153 that will produce frequency 2 for the third MSGEQ7 chip.
`Si.init(25000000L);
Si.setFreq(0, 104570);
Si.setFreq(1, 166280);
Si.setPower(0, SIOUT_8mA);
Si.setPower(1, SIOUT_8mA);
Si.enable(0);
Si.enable(1);
`
I didn't watch the whole video and I've never actually used the MSGEQ7 but I know a little about it. The video doesn't tell you how to do it?
Normally the MSGEQ7 uses it's own built-in oscillator, nominally at 165kHz according to the datasheet. Do you have an oscilloscope, or a multimeter that measures frequency?
I assume you can alter the frequency by changing 200K resistor and 33pF capacitor shown on the datasheet. You could guess that increasing the capacitor would proportionally lower the frequency range but it would be better if you can measure it.
From the bit of video I did watch, it works surprisingly well! Normally when you increase the number of bands you need to narrow the width of the filters (for less overlap) but you can't do that with the MSGEQ7.
See if this helps.
'21 Bands Spectrum Analyzer - EasyEDA open source hardware lab
This is exactly what I'm trying to do. The code shown in my post is run is setup to configure the Si5351 to generate 3 frequencies - 0,1,2. My example shows the values for 2 frequencies - one for each MSGEQ7 to provide 2x7 or 14 channels. I want 21 channels, thus I need to add one MSGEQ7 and configure the third frequency.