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by PiGraham
Sat Jul 24, 2021 1:52 pm
Forum: General discussion
Topic: Motors not spinning with GPIO pins
Replies: 4
Views: 118

Re: Motors not spinning with GPIO pins

The Amazon page image shows the battery pack at the back with two 18650 cells in a holder.

Image

From your photo you have no battery pack.
by PiGraham
Tue Jul 20, 2021 10:37 am
Forum: General
Topic: Pi Pico - the most user un-friendly MCU?
Replies: 231
Views: 6584

Re: Pi Pico - the most user un-friendly MCU?

Thanks, I emailed you.
by PiGraham
Tue Jul 20, 2021 7:54 am
Forum: General discussion
Topic: MSOffice on a Pi-400
Replies: 75
Views: 2324

Re: MSOffice on a Pi-400

In terms of total number of ARM-based desktop PCs sold, would the Pi 4B and 400 market share be large or small? I don't actually know any other device one might want to install ARM Windows on. Surface Pro X from some company based in Redmond I believe ... https://en.wikipedia.org/wiki/Surface_Pro_X...
by PiGraham
Mon Jul 19, 2021 1:17 pm
Forum: General
Topic: Pi Pico - the most user un-friendly MCU?
Replies: 231
Views: 6584

Re: Pi Pico - the most user un-friendly MCU?

lurk101 wrote:
Mon Jul 19, 2021 11:24 am
nick.mccloud wrote:
Mon Jul 19, 2021 9:33 am
I've added you as a friend if you want to PM me.
Adding a friend enables PMs?
It seems not.

I've attempted contact on linkedin.
by PiGraham
Mon Jul 19, 2021 8:38 am
Forum: General
Topic: Pi Pico - the most user un-friendly MCU?
Replies: 231
Views: 6584

Re: Pi Pico - the most user un-friendly MCU?

nick.mccloud wrote:
Sat Jul 17, 2021 9:09 am
Even small PIC projects MPLab IDE X can take a while.
Nick,
A quick off topic question. Are you available to consult on a small PIC software related task?
by PiGraham
Mon Jul 19, 2021 7:02 am
Forum: Graphics, sound and multimedia
Topic: USB speakers not recognized in RP 4
Replies: 17
Views: 455

Re: USB speakers not recognized in RP 4

LTolledo wrote:
Sun Jul 18, 2021 9:55 pm
rated 6W (3W + 3W)
DC5V 500mA
Those specs are questionable.
Granted the audio power will be peak, not RMS, still I wonder how you get 6W audio out from 2.5W electrical power in.
by PiGraham
Sat Jul 17, 2021 6:21 pm
Forum: Graphics, sound and multimedia
Topic: USB speakers not recognized in RP 4
Replies: 17
Views: 455

Re: USB speakers not recognized in RP 4

are they listed if you run

Code: Select all

lsusb

or 

dmesg
by PiGraham
Sat Jul 17, 2021 5:11 pm
Forum: Automation, sensing and robotics
Topic: Need Help: Simple Home Power Status Detector
Replies: 13
Views: 484

Re: Need Help: Simple Home Power Status Detector

I know nothing about this device, but something like it might fit your need.

http://doc.mokotechnology.com/index.php?s=/page/166

Plugin mains power monitor measures V A W and has Bluetooth I/F and an API
by PiGraham
Fri Jul 16, 2021 1:43 pm
Forum: Beginners
Topic: Trying to read ADC only for a certain amount of time
Replies: 2
Views: 109

Re: Trying to read ADC only for a certain amount of time

You need to control your sample rate & number of samples somehow. You could call sleep after each sample. If you sample once every second and do your elapsed time loop for 10 seconds you will have ten samples stored. You could use a timer that ticks every second and count each sample until you g...
by PiGraham
Wed Jul 14, 2021 6:55 am
Forum: General discussion
Topic: Collect data using sensors connected to Raspberry Pi and display the data on an android application
Replies: 5
Views: 255

Re: Collect data using sensors connected to Raspberry Pi and display the data on an android application

Two basic approaches: Write the data to a third party server on the internet somewhere and write your client on the phone to access Build your own server on the Pi and expose that to the internet, probably by port mapping on your router. For the first you could use a public MQTT broker (server) rand...
by PiGraham
Tue Jul 13, 2021 9:18 am
Forum: Python
Topic: event_callback (RISING - FALLING)
Replies: 17
Views: 457

Re: event_callback (RISING - FALLING)

Well the first thing I see is you have no pull up or down on your button either with external resistors or by a setting in your code, I did mention this when I posted the example. (might be a good idea to go read my example post again) You are also looking for a rising edge but you have your button...
by PiGraham
Tue Jul 13, 2021 8:46 am
Forum: Python
Topic: event_callback (RISING - FALLING)
Replies: 17
Views: 457

Re: event_callback (RISING - FALLING)

I believe that GPIOZero can handle both edges. https://gpiozero.readthedocs.io/en/stable/api_input.html#regular-classes when_pressed The function to run when the device changes state from inactive to active. This can be set to a function which accepts no (mandatory) parameters, or a Python function ...
by PiGraham
Mon Jul 12, 2021 1:04 pm
Forum: Troubleshooting
Topic: Can't type "at" symbol
Replies: 10
Views: 232

Re: Can't type "at" symbol

It seems you have a US keyboard. Followed by: As other have stated, @ is SHIFT ' to the left of ENTER Therefore, @ is SHIFT 2 (key to the left of 3). OP Specifically asked where @ was on a UK keyboard, why are you muddying the water? It's fairly obvious OP has a non UK keyboard (Likely US) configur...
by PiGraham
Mon Jul 12, 2021 10:49 am
Forum: Troubleshooting
Topic: Can't type "at" symbol
Replies: 10
Views: 232

Re: Can't type "at" symbol

Hello. So far I'm really enjoying my new Pi 4 B, but there's one problem. I set it up with British English as the default locale; now pressing Shift + 2 types " instead of "@". Very annoying when you're trying to type an email address. I tried enabling the en_US locale and rebooting;...
by PiGraham
Fri Jul 09, 2021 10:46 am
Forum: Camera board
Topic: Questions on rolling shutter camera frame
Replies: 11
Views: 388

Re: Questions on rolling shutter camera frame

https://www.raspberrypi.org/forums/download/file.php?id=47911 It looks like the lowest 2 is the first illuminated digit in the frame. Then 9 then 1, each progressively a bit higher. Then the next 2,9,1 and so on, with exposure ending when the last 1 at the top is lit. You could get that with global...
by PiGraham
Fri Jul 09, 2021 10:34 am
Forum: Camera board
Topic: Questions on rolling shutter camera frame
Replies: 11
Views: 388

Re: Questions on rolling shutter camera frame

The effect I described can and does happen with a global shutter. During one exposure time each digit is briefly illuminated multiple times because the multiplexing rate is faster than the inverse of the exposure time. Because of motion each "imprint" on the sensor is at a different posit...
by PiGraham
Fri Jul 09, 2021 9:43 am
Forum: Camera board
Topic: Questions on rolling shutter camera frame
Replies: 11
Views: 388

Re: Questions on rolling shutter camera frame

It will be the multiplexing on the 7 segment. Each LED on it will be flashing on and off completely unsynchronised with the rolling shutter on the camera. That timing will determine where a segment appears on the image, and how many times it appears. It isn't the rolling shutter that is causing thi...
by PiGraham
Fri Jul 09, 2021 9:23 am
Forum: Camera board
Topic: Questions on rolling shutter camera frame
Replies: 11
Views: 388

Re: Questions on rolling shutter camera frame

It will be the multiplexing on the 7 segment. Each LED on it will be flashing on and off completely unsynchronised with the rolling shutter on the camera. That timing will determine where a segment appears on the image, and how many times it appears.
by PiGraham
Thu Jul 08, 2021 6:12 pm
Forum: Beginners
Topic: Push Button GPIO to tkinter gui display
Replies: 14
Views: 424

Re: Push Button GPIO to tkinter gui display

Thank you! I can see that my physical computing code will need to engage in a different way than my display code. My research is circling asyncio loops. Would something like a get_running_loop() and a get_event_loop() be the direction in which you are pointing? Any additional information would be a...
by PiGraham
Thu Jul 08, 2021 3:15 pm
Forum: Beginners
Topic: Push Button GPIO to tkinter gui display
Replies: 14
Views: 424

Re: Push Button GPIO to tkinter gui display

I think your problem will be that the GUI is is it's event loop and your main loop will not be cycling.
You could try setting change callbacks for the gpio to set a start time and a stop times in global variables and then raise an event to trigger an update in the GUI.
by PiGraham
Fri Jul 02, 2021 7:45 am
Forum: Beginners
Topic: VNC shows the connection was closed remotely when i unplug the ethernet cable
Replies: 6
Views: 177

Re: VNC shows the connection was closed remotely when i unplug the ethernet cable

That is to be expected if Your VNC connection is to a specific IP address then unplugging the cable will remove the associated IP address. Just connect to the IP address of the Wi-Fi adapter when using Wi-Fi. You might find that connecting using hostname might allow the connection. try connecting to...
by PiGraham
Tue Jun 29, 2021 7:07 am
Forum: Beginners
Topic: Summer Project! Need Guidence Please.
Replies: 8
Views: 294

Re: Summer Project! Need Guidence Please.

It looks like image based techniques use satellite imagery to detect deforestation. This might be interesting. The simplest method of early detection of tree cutting is to regularly monitor the forest area either manually or using some automatic techniques. As tree cutting generates lot of noise, it...
by PiGraham
Mon Jun 28, 2021 7:08 pm
Forum: Beginners
Topic: Summer Project! Need Guidence Please.
Replies: 8
Views: 294

Re: Summer Project! Need Guidence Please.

rpdom wrote:
Mon Jun 28, 2021 4:28 pm

Software: Motion.
Trees move naturaly, which will generate vast numbers of triggers in Motion.

Maybe tensor flow to recognise people among the trees, or vehicles of certain types driving though forest.
by PiGraham
Mon Jun 28, 2021 4:02 pm
Forum: Beginners
Topic: Summer Project! Need Guidence Please.
Replies: 8
Views: 294

Re: Summer Project! Need Guidence Please.

I want to build this device in order to catch and record illegal tree cutting in North Macedonia. Aside from technical details of software, solar power etc, do you know how to !catch and record illegal tree cutting"? Where would you put cameras? What view would they have of trees? What would t...
by PiGraham
Fri Jun 25, 2021 7:36 am
Forum: General programming discussion
Topic: How to generate an audio tone from a program
Replies: 13
Views: 748

Re: How to generate an audio tone from a program

PiGraham Thanks for the rply. I am trying to develop a theramin so I need to slide frequency and volume depending on the input fro two sensors. With pygame I cannot change the frequency fast enough. MIDI may be useful but I am afraid I don't see how. This video might give you an idea of what can be...

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