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3

This is not a software issue, but a fact of data transmission. There are signal losses in wired just as in wireless signals. This is either due to the resistance/capacitance of the wire or the noise pickup from other signals. You could experiment to see what could be done to improve it: higher current through the wires, shielding/twisted pairing.


2

I can't answer for Python since I'm not very familiar with it, but I suspect there is some way to run an external program. And if there is, then what you have there is exactly what you need to run a netlist: the -b command line switch. See more about them in the help, under LTspice > Modes of Operation > Command Line Switches. Extensions do not matter, ...


2

Transfer of a max. sized CAN frame is roughly ~100µs (at 1MBit/s). Everything else I guess is SW. But Linux + phyton is not a Realtime environment or fast in first place. You need at least a core with FiFo scheduling policy, and get rid of python - use compiled language like C++. But even that might just bring a minor improvement. You might need a real RTOS (...


2

The ADS1256 has a single ADC that is multiplexed between all channels. If you read from a single channel continuously, then you can get 30000 samples per second out of it. Since switching channels takes a couple of commands and some settling time before you get valid data, the total throughput drops when you start switching channels. Page 21 of the datasheet ...


1

After some research I ended up finding the solution. The ltspice package for python should be updated. To anyone dealing with the same problem, better change the ltspice.py file with the one found here


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The problem here is that there are different types of logarithms (base e, 2, 10) and different starting points (here 0.001). I get the same bins for any base. see below. note the aproprate usage of log10, log and log2 functions which are consistent with the base= parameter. >>> import numpy as np >>> np.logspace(np.log10(0.1), np.log10(10),...


1

I note your pins SCK and MOSI are the other way around from the adafruit examples which say dots = dotstar.DotStar(board.SCK, board.MOSI, 30, brightness=0.2) So it's possible that although you're using the SPI pins, the clock and data can't take advantage of the hardware transceiver. You might be forcing it to send the bits in software, which in Python, won'...


1

Protip: never run 'pip3 install' without --user; when not working in a special prefix! othewise, it installs stuff in system-wide locations, which are different for different systems and sometimes (and that's the case here) not even looked in by default. So, uninstall what you've installed using pip3 again, then set up a Python virtual env: python3 -m venv ...


1

Below is a script to measure delay in Ch1 - Ch2 raising edges with MDO4042 Tek scope. I had to improvise to make delays between Ch1 and 2, so please tune the script to your needs. #Script to measure delay with MDO4024C Mixed Domain Oscilloscope import time import pyvisa as visa rm = visa.ResourceManager() print('Available devices: ') print(rm.list_resources()...


1

Your information about your circuit in the blue rectangle is very sparse, but I assume it is just representing the relay (note 1). If that is the case then you should expect problems because the rPi output cannot source more than 50mA according to this source and that would be at reduced voltage even. The coil is specified at 25 Ohm and typical 3V, so this ...


1

From your 2nd picture it looks like you need a linear-phase FIR, as opposed to an IIR. The main difference is that FIRs can have perfectly linear phase, thus a perfectly flat group delay, which means all the frequencies are delayed by the same amount, while IIRs have non-linear phase by design, thus a nonlinear group delay, resulting in smearing in time ...


1

If your wanted band is 3 to 50 Hz, then it will not be possible to notch 50 Hz out with any practical filter without losing some of the top end of your band. Can you use a digital filter, or must you use an analogue one? It depends on the signal to noise ratio at the ADC. If your 50 Hz interference is at such a level it's causing you to turn the gain down ...


1

There isn't a definitive upper limit to the latency. The OS may delay running your process or running the FTDI driver or sending the USB packets randomly. If e.g. another USB device on the same bus consumes a lot of bandwidth, the FTDI packets may experience a long delay. If other CPU-intensive processes are running, your program might not even be scheduled ...


1

Yes you can. No they are not the same. a) You have to model your circuit in python, using transfer function rules (e.g. for voltage dividers, opamps etc...), and vary the components (randomly) to update the transfer function. OR b) generate a spice netlist with selected (random) component values and run it in spice. This is not efficient, as you generate a ...


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