Go to advanced search

by MarkTF
Tue Jun 23, 2020 3:16 pm
Forum: General discussion
Topic: Robust outdoor GPS-logger
Replies: 12
Views: 1381

Re: Robust outdoor GPS-logger

Robustness is largely a function of how the device is packaged. The electronics should operate fine over any reasonable temperature range, but will need to be protected against moisture and such. Far be it from me to discourage anyone from electronics tinkering, but the obvious solution is to downlo...
by MarkTF
Tue Jun 23, 2020 2:40 pm
Forum: General discussion
Topic: What's the minimum Amp to boot a Raspberry
Replies: 10
Views: 1300

Re: What's the minimum A to boot a Raspberry

IME with lab supply those are not even close to the 'minimum' current requirements. My results were much more closely aligned with rpdom's table. Somewhat lower with a big cap added. Interesting. I wonder why there's such a big difference. I'd submit they are answers to different questions. The tab...
by MarkTF
Mon Jun 15, 2020 4:54 am
Forum: General discussion
Topic: best, safest and easiest way to connect pi 3 b+ with arduino uno
Replies: 10
Views: 906

Re: best, safest and easiest way to connect pi 3 b+ with arduino uno

I just want to communicate back and forth from rpi to arduino and vice versa and want to supply each device with its own power supply because as i mentioned before its big project and needs huge power supply for both. The project is big enough and i dont want to add any more components as well. i w...
by MarkTF
Mon Jun 01, 2020 12:22 pm
Forum: General discussion
Topic: Python coding in Spyder 3
Replies: 5
Views: 724

Re: Python coding in Spyder 3

The Spyder console isn't a terminal, so it behaves differently to the terminal control characters used by "curses".

This might help, but I haven't tried it: https://pypi.org/project/spyder-terminal/

If not, then develop in the IDE, and execute in a terminal window.
by MarkTF
Fri May 08, 2020 2:12 pm
Forum: General discussion
Topic: Only run python on rasberry pi
Replies: 19
Views: 1811

Re: Only run python on rasberry pi

If I'm reading the Naumann Term Paper right, he turned off some compiler optimizations to get the RPi version of bare metal MicroPython to run.

https://www.snaums.de/static/resources/2017-12-mpy.pdf
by MarkTF
Thu May 07, 2020 12:24 pm
Forum: Python
Topic: Looking for python code for Triangulation or Trilateration (I think)...
Replies: 2
Views: 1358

Re: Looking for python code for Triangulation or Trilateration (I think)...

This is my implementation based on the Wikipedia "multilateration" article: https://en.wikipedia.org/wiki/True_range_multilateration This gives a pair of solution points for the target platform and two reference point measurements. # 2D Multilateration algorithm with 2 platforms # Input is...
by MarkTF
Wed May 06, 2020 9:46 pm
Forum: General discussion
Topic: Resoldering Ram on Rpi4?
Replies: 24
Views: 1904

Re: Resoldering Ram on Rpi4?

Please add me to the list of people who want a Pi 4 with 16 GB. Browser tabs, caches, temp directories in tmpfs, PDF viewer, IDE, compiling in the background plus sometimes having to use Firefox and Chromium simultaneously....I'm now at the point where even with 4 GB everything crashes twice a day ...
by MarkTF
Thu Apr 23, 2020 12:12 pm
Forum: Advanced users
Topic: Thermal differences between mutiple Pi 4B units
Replies: 37
Views: 4543

Re: Thermal differences between mutiple Pi 4B units

Have you tried measuring temperature with an external monitor? like an infrared one or a contact one? It could be useful to detect differences in calibration between internal temp sensors. infrared ones should be sensitive enough to detect 2 degrees baseline differences maybe there are even more pr...
by MarkTF
Tue Apr 14, 2020 2:37 pm
Forum: General discussion
Topic: Dual microphone noise cancellation
Replies: 16
Views: 1734

Re: Dual microphone noise cancellation

In effect you're more likely to be successful at emphasising the more narrow-band bird and forest sounds above a white noise background with just one microphone than trying to subtract the noise of the sea more computationally. . . . There are a few easy(ish) to use DSP packages for Linux that work...
by MarkTF
Tue Apr 14, 2020 1:26 pm
Forum: General discussion
Topic: Dual microphone noise cancellation
Replies: 16
Views: 1734

Re: Dual microphone noise cancellation

Without using two identical capsules sited very close together you are not going to have much success with good cancelling over a range of frequencies. Waves sound very much like noise which does cover a wide spectrum. They're identical capsules which are very close together, looking in opposite di...
by MarkTF
Mon Apr 13, 2020 8:24 pm
Forum: General discussion
Topic: Use all laptop peripherals for Raspberry Pi
Replies: 8
Views: 546

Re: Use all laptop peripherals for Raspberry Pi

At the time the laptop has Wary Puppy Linux Distro installed, I guess TinyCore would be even more lightweight. :D I was hoping to install Ubuntu Mate in the Raspberry Pi and hopefully run some modern applications, taking advantage of the Laptop peripherals. Is this really that bad idea? :? If you a...
by MarkTF
Mon Mar 30, 2020 6:37 pm
Forum: General discussion
Topic: Using samsung fast charge for RPI3 B+
Replies: 16
Views: 1717

Re: Using samsung fast charge for RPI3 B+

The Pi3 B+ by itself should run fine on that power supply. The 2.5 A recommendation allows for the Pi plus accessories so it will depend upon your configuration whether a 2.0 A supply is sufficient. USB flash sticks in particular can draw relatively large currents. There's also a concern as to wheth...
by MarkTF
Fri Mar 27, 2020 4:50 pm
Forum: General discussion
Topic: Raspberry Pi randomly shuts down when I plug arduino uno in with circuit
Replies: 4
Views: 564

Re: Raspberry Pi randomly shuts down when I plug arduino uno in with circuit

It's been a while since I've done Arduino on RPI, but I've seen this. It's likely due to surge current when the Arduino is plugged in causing the RPi voltage to sag. The USB specification says a device should present no more than 10 uF capacitance to USB power upon connection. The Arduino Uno refere...
by MarkTF
Tue Feb 04, 2020 4:09 pm
Forum: General discussion
Topic: Battery Level Indicator -- While Charging
Replies: 17
Views: 5058

Re: Battery Level Indicator -- While Charging

In the figure, the red line is the charging current going into the batter, the blue line is the state of charge (2000 mA Hr capacity battery), and the black line is the voltage across the battery terminals during charge. LiPo chargers typically use a two stage charging process. First is constant cur...
by MarkTF
Wed Dec 11, 2019 2:27 pm
Forum: General discussion
Topic: [Solved] Annoying feature of 'apt-get uprgade'
Replies: 42
Views: 4013

Re: Annoying feature of 'apt-get uprgade'

I would be VERy surprised if there is a coding error in apt that has not been spotted elsewhere - it's not like we are the only people using it. According to the original post listing, it looks like the response character string "n <backspace> d" was interpreted as if it were "n"...
by MarkTF
Wed Nov 27, 2019 1:47 pm
Forum: General discussion
Topic: Raspberry pi ecological footprint
Replies: 60
Views: 4474

Re: Raspberry pi ecological footprint

By comparing weight, price and quantity alone we already can discount the Pi as a major contributor to the world's energy consumption and ecological disaster problems. It's impact is lost in the noise! Whether or not the Pi is a major contributor to world energy consumption and ecological impacts i...
by MarkTF
Fri Oct 11, 2019 7:24 pm
Forum: General discussion
Topic: Will Quick Charge 3.0 provide consistent power to Raspberry Pi 4B?
Replies: 10
Views: 2589

Re: Will Quick Charge 3.0 provide consistent power to Raspberry Pi 4B?

Yes, I"m just wondering if you plug a non-Quick Charge device into the Quick Charge 3.0 port, will it provide the voltage and amps required from the device. In this case, will the Pi 4 request 5V/3Amp, and will the Quick Charge 3.0 port provide that on each port? The Pi won't negotiate anythin...
by MarkTF
Fri Oct 11, 2019 5:48 pm
Forum: General discussion
Topic: Will Quick Charge 3.0 provide consistent power to Raspberry Pi 4B?
Replies: 10
Views: 2589

Re: Will Quick Charge 3.0 provide consistent power to Raspberry Pi 4B?

I need to power 4 Raspberry Pi 4B clusters and was wondering if this charger will consistently provide 5V/3A to all 4 Pi's? https://www.amazon.com/dp/B07GGMLSD3/?coliid=I3A004O8XVNRO7&colid=2I5CGTBT9RPVY&psc=1&ref_=lv_ov_lig_dp_it There's no benefit to using a charger with Qualcomm's Qu...
by MarkTF
Fri Oct 11, 2019 2:53 pm
Forum: General discussion
Topic: Will Quick Charge 3.0 provide consistent power to Raspberry Pi 4B?
Replies: 10
Views: 2589

Re: Will Quick Charge 3.0 provide consistent power to Raspberry Pi 4B?

I've used something similar to this to power multiple single board computers. Per the specifications it should have plenty of capacity, and, coming from a reputable brand, it probably more or less meets the stated specifications. That said, unless you find someone who has used that particular device...
by MarkTF
Thu Aug 22, 2019 8:22 pm
Forum: Off topic discussion
Topic: Best Raspberry Pi Alternatives 2019
Replies: 65
Views: 24865

Re: Best Raspberry Pi Alternatives 2019

I'm not sure if CHIP is a good example. They were either very naïve or intentionally fraudulent. Either way, they're gone. I wonder if my Pocket CHIP even works still? Even at the time I couldn't understand the business model by which NextThing CHIP ever figured to turn a profit, but I don't think ...
by MarkTF
Thu Aug 22, 2019 7:58 pm
Forum: Off topic discussion
Topic: Best Raspberry Pi Alternatives 2019
Replies: 65
Views: 24865

Re: Best Raspberry Pi Alternatives 2019

. . . Beagle Board is a great system, but trying to figure it out as a “noob” is annoying compared to the ease of using a Pi. . . . I don't get this statement. The BeagleBone stuff is down on raw horsepower and the core chip is more oriented to embedded control applications which limits its market,...
by MarkTF
Tue Jul 30, 2019 2:25 pm
Forum: General discussion
Topic: Raspberry pi for coding on machine level?
Replies: 30
Views: 4177

Re: Raspberry pi for coding on machine level?

Would you recommend coding for the Raspberry Pi, on a machine code level? I realize that machine code is very device specific. And since the Pi has been created in the millions (probably sold more than any PC, phone, or even Mac), the highest chance to learn how to work with machine code, is to do ...
by MarkTF
Tue Jul 23, 2019 4:30 pm
Forum: General discussion
Topic: do spectrum analyzer with arduino due and raspberry pi
Replies: 3
Views: 824

Re: do spectrum analyzer with arduino due and raspberry pi

Olgac wrote:
Tue Jul 23, 2019 1:17 pm
"float object cannot be interpreted as an integer"
Something that is supposed to be an integer type is a float type. Probably num/downsample.
by MarkTF
Wed Jun 05, 2019 8:51 pm
Forum: General discussion
Topic: Python code is being executed slowly on Pi 3 B+
Replies: 14
Views: 1513

Re: Python code is being executed slowly on Pi 3 B+

Any help will be appreciated. I'd start by getting rid of passing results via global variables and explicitly return those values from each function definition. I suspect you might be generating some large arrays in the function calls that aren't actually used, but it's very hard to follow the prog...

Go to advanced search