I want to use some other ways to generate negative voltage. I want try buck-boost.
The current of +10V rail is 15mA, measured with DMM.
Voltage ripple = 1510^-3 mA(1/20000 Hz)/(1010^-6 F)=0.075V.
I'm considering to change the U10 OPAMP which used for wave generator to ±7V. Thus, I can remove ±10 rail for OPAMPs voltage supply. The output voltage of ±3V can be covered with this configuration.
Sorry for not having joined the last meetings. I've been a little busy again, about to present something fancy again, today noon at CLT: https://chemnitzer.linux-tage.de/2022/en/programm/beitrag/226
During FOSSASIA Summit, I might be in Berlin, not 100% sure yet. Let me know if you'd like to meet. I'd arrive at the Wednesday, and stay until Sunday evening. Will let you know when it's for sure. :-)
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One issue I ran into with this I2C sensor:
https://github.com/tasmota/docs/pull/954/files
The docs led me to believe the boards had the same pin order.
I.e., I had GND and SDA swapped.
Anyhow, there's still nothing detected. I will see if it works with an ESP board here when I have the time.
Could be because of:
Only a single AHT10 can be connected to the I^2^C bus and no other I^2^C devices can be connected.
The pslab's I2C bus also has the mcp4728 on it, as well as the rtc if you're using the v6 prototype.
https://twitter.com/OrangeCMS/status/1507728538782384135?t=mH_mtIOMvLb4zebfKWwRQw&s=19
For FOSSASIA Summit, I will merely have a draft, not even a PoC, I think. I know that it's doable, it's just complex unless you've done it already. ^^
it can now edit and save UEFI based firmware, and also analyze AMD PSP and coreboot filesystems 🐙
fossasia/pslab-desktop#697
I'm want to test transmission through diy guitar effects, so pslab wavegenerator -> some device -> pslab oscilloscope, everything automated via python. I can of course send sinusodial signals (one frequency at a time) from the waveformgenerator to the oscillopscope, but that's inefficient. One could do a sinus-sweep through the audible spectrum or use white noise.
This is how I basically create my waveform:
from pslab import WaveformGenerator
wavegen = WaveformGenerator()
wavegen.load_function("SI1", lambda x: 0.5*np.sin(x), [0, 2*np.pi])
wavegen.generate(channels = 1, frequency = 100)I don't understand how exactly the frequency enters the formula. For a sin-sweep, I want to modulate the frequency with another sinusodial function with a low frequency - but in the lambda function above the frequency is not stated explictly. Is there a way to pass something like this to load_function:
def myfunction(frequency, phase, time):
return np.sin(frequency * time + phase)Another way would be to somehow generate whitenoise from one output...that would basically mean I have to replace the sin function with np.random.random()or something...but there I have the same problem, that I don't understand exactly how the frequency and timestep is passed to the function.
I hope this is understandable, and thank you so much in advance!
To load more complicated functions than the load_function method allows (such as functions of more than one variable), you can use the load_table method instead. It let's you load a 512 values long list into the pslab's memory, the values of which the pslab will do its best to reproduce when you call generate. It loops over the 512 values every 1/frequency seconds.
However, the pslab is not able to accurately reproduce signals that contain harmonics above 5 kHz. You can try to load 512 values from np.random.random into memory and see what you get, but I'm not sure how good the result will be. It's definitly an interesting experiment!
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