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by Idahowalker
Tue Jan 15, 2019 2:14 am
Forum: Troubleshooting
Topic: Static shock causing false GPIO detection
Replies: 14
Views: 670

Re: Static shock causing false GPIO detection

Got an Ohm meter? If so what is the resistance reading between the case and the RPi common, GND? Ohm with and without cables connected. Connect one cable at a time and ohm. If you get less then Infinity that's a problem. When you take the Ohm measurements do not touch the case or the ohm meter leads...
by Idahowalker
Mon Jan 14, 2019 3:10 am
Forum: Python
Topic: GPIO Wait For Edge On More Than One Pin
Replies: 3
Views: 477

Re: GPIO Wait For Edge On More Than One Pin

Using your favorite search engine look up 'GPIO callbacks" have the callbacks set a global and have your loop check the status of the global is one way to do this task.
by Idahowalker
Thu Jan 10, 2019 2:35 pm
Forum: Python
Topic: Converting Float Values Into Bytes for SPI
Replies: 8
Views: 727

Re: Converting Float Values Into Bytes for SPI

When I send floats to a Arduino Uno, Mega, Due, STM32, and ESP32 using a RPi serial port I sent the data as bytes by using sSend = "blah blah blah 1234.567" sSend = sSend.encode('utf-8') Perhaps that will work in your situation? Also, sSend = b("blah blah blah 1234.5678") works as well Thanks For t...
by Idahowalker
Thu Jan 10, 2019 12:51 pm
Forum: Automation, sensing and robotics
Topic: "UFO Radar" with magnetometer
Replies: 7
Views: 552

Re: "UFO Radar" with magnetometer

I have a MPU9250 that comes with a magnetometer but your most likely looking for a 3 axis Fluxgate magnetometer. Thanks! Can you explain in layman's terms how a 3-axis fluxgate magnetometer is different from what the Sense Hat is equipped with? Sensitivity. The least sensitive device would be a hal...
by Idahowalker
Thu Jan 10, 2019 12:23 pm
Forum: Automation, sensing and robotics
Topic: "UFO Radar" with magnetometer
Replies: 7
Views: 552

Re: "UFO Radar" with magnetometer

I have a MPU9250 that comes with a magnetometer but your most likely looking for a 3 axis Fluxgate magnetometer.
by Idahowalker
Thu Jan 10, 2019 12:12 pm
Forum: Python
Topic: Converting Float Values Into Bytes for SPI
Replies: 8
Views: 727

Re: Converting Float Values Into Bytes for SPI

When I send floats to a Arduino Uno, Mega, Due, STM32, and ESP32 using a RPi serial port I sent the data as bytes by using

sSend = "blah blah blah 1234.567"
sSend = sSend.encode('utf-8')

Perhaps that will work in your situation?

Also, sSend = b("blah blah blah 1234.5678") works as well
by Idahowalker
Wed Jan 09, 2019 7:36 pm
Forum: Troubleshooting
Topic: HELP NEEDED! Couldn’t transmit through Uart
Replies: 3
Views: 210

Re: HELP NEEDED! Couldn’t transmit through Uart

Have you tried a loop back test? With a loopback test you can see if the RPi is set up properly. Entering the words 'raspberry pi serial loopback' into your favorite search engine will give you a plethora of options for a loop back test. Once you have completed a loopback test you can move outside o...
by Idahowalker
Wed Jan 02, 2019 9:13 pm
Forum: Beginners
Topic: How to solder BME280 in a robust way to NodeMCU so that I get no heating issues (which cause false readings)
Replies: 6
Views: 622

Re: How to solder BME280 in a robust way to NodeMCU so that I get no heating issues (which cause false readings)

My first question is where is the RPi in this scheme? Next, I have a GPS unit I built around a ESP32 that has a temperature / barometer / blah / blah sensor. I soldered the sensor, in a box, as far away from the ESP32 as I could get it and I put a few vent holes in the box for ventilation. I then ra...
by Idahowalker
Sat Dec 29, 2018 4:46 pm
Forum: Python
Topic: How to compare current and next day
Replies: 27
Views: 1407

Re: How to compare current and next day

vajra11 wrote:
Sat Dec 29, 2018 3:42 pm
Idahowalker wrote:
Sat Dec 29, 2018 1:40 pm

You created a global variable but you did not declare count in the local functions as global.
I declared global but still giving error perhaps I am making a mistake
Look more closely at the code of my initial response.
by Idahowalker
Sat Dec 29, 2018 1:40 pm
Forum: Python
Topic: How to compare current and next day
Replies: 27
Views: 1407

Re: How to compare current and next day

I seen #!/usr/bin/env python from tkinter import * from time import sleep import RPi.GPIO as GPIO import time import datetime GPIO.setmode(GPIO.BCM) INPUT_PIN = 21 GPIO.setup(INPUT_PIN, GPIO.IN) count = 0 def my_callback(channel1): global count ################################################# <<< ...
by Idahowalker
Sat Dec 29, 2018 1:58 am
Forum: Beginners
Topic: OLED HAT - partially problem
Replies: 3
Views: 533

Re: OLED HAT - partially problem

What are you expecting the display to show?

What is the code you are using to send stuff to the display?
by Idahowalker
Fri Dec 28, 2018 7:50 pm
Forum: Beginners
Topic: Which pi should I buy?
Replies: 15
Views: 1249

Re: Which pi should I buy?

Should one go for the latest and greatest, as a general rule, if one could? Getting into pi for the first time, coming from programming background. In the world of software the latest version is best waited out for a bit. Is the same apply here? Or one should buy the latest? Programmer. Buy the bes...
by Idahowalker
Sun Dec 23, 2018 3:15 pm
Forum: Python
Topic: How to stop script after multiple activations
Replies: 6
Views: 727

Re: How to stop script after multiple activations

You could count the number of times the callback runs and then at the point of count reached detach the callback.

iCount = iCount + 1

if iCount == 10

GPIO.remove_event_detect(channel)

and you might want to break out of your infinite loop after the callback remove.
by Idahowalker
Sat Dec 22, 2018 12:34 pm
Forum: Automation, sensing and robotics
Topic: Raspberry Pi official case gpio problem
Replies: 1
Views: 1521

Re: Raspberry Pi official case gpio problem

I use a ribbon cable connected to the RPi, the case closes with the ribbon cable. I attach the ribbon cable to a RPi HAT development board and make my connections from there.
by Idahowalker
Fri Dec 21, 2018 12:43 pm
Forum: Python
Topic: Pi to Pi Communication
Replies: 2
Views: 576

Re: Pi to Pi Communication

Post the Python code you are using to do all this and the error messages you are getting.
by Idahowalker
Tue Dec 18, 2018 12:39 am
Forum: Troubleshooting
Topic: Need help with level shifter from 3.3V to 5V
Replies: 6
Views: 1417

Re: Need help with level shifter from 3.3V to 5V

Perchance is the 5V common and the 3.3V common tied together at some point, perhaps at the level shifter?

Bring the 5V common to the level shifter ground. There is a connection for the 5V common on the high side.
by Idahowalker
Mon Dec 17, 2018 12:12 pm
Forum: Python
Topic: Have a certain time to do something
Replies: 2
Views: 277

Re: Have a certain time to do something

import time class cRuntime(): def __init__(self): self.iStartTime = int( time.time() ) self.iRunTimeDays = 0 self.iRunTimeHours = 0 self.iRunTimeMinutes = 0 self.iRunTimeSeconds = 0 def fDoRunTime( self ): self.iRunTimeDays = divmod( (int(time.time()) - self.iStartTime), 86400 ) self.iRunTimeHours =...
by Idahowalker
Sat Dec 15, 2018 4:27 am
Forum: Beginners
Topic: Programming DHT11 with Python
Replies: 2
Views: 342

Re: Programming DHT11 with Python

Entering into my favorite search engine the words "python dht11" nets me a whole bunch of pages like this one: https://github.com/szazo/DHT11_Python
by Idahowalker
Fri Dec 14, 2018 9:51 pm
Forum: Beginners
Topic: Beginner IR sensor question
Replies: 1
Views: 144

Re: Beginner IR sensor question

Yes, you can wire them as an OR gate.
by Idahowalker
Fri Dec 14, 2018 5:13 pm
Forum: Other projects
Topic: How to make a A.I. using raspberry pi 3 and python
Replies: 2
Views: 406

Re: How to make a A.I. using raspberry pi 3 and python

if you could post your code then, perhaps, someone could figure out where the output went.

Please use code tags when posting the code.
by Idahowalker
Fri Dec 14, 2018 5:11 pm
Forum: Automation, sensing and robotics
Topic: Adafruit IR break beam sensor
Replies: 4
Views: 1526

Re: Adafruit IR break beam sensor

Placing a collimator around the IR receiver might, also, help with some object detection discrimination. Something as simple as a tube placed around the receptor opening might get rid of scatter and work to lessen IR sensitivity.
by Idahowalker
Tue Dec 11, 2018 7:18 pm
Forum: Beginners
Topic: Feeding output as input on RPi
Replies: 3
Views: 252

Re: Feeding output as input on RPi

You want to send a 1 or 0 out of a GPIO pin and you want to read if the GPIO pin is sending a 1 or a 0?

Yes, you can feed to output of a GPIO pin to an input of a GPIO pin, no problem.

Such is very useful for something like a serial loop back test.
by Idahowalker
Mon Dec 10, 2018 11:18 pm
Forum: Other projects
Topic: [Beginner] A musical alarm + turning the lights on in the morning?
Replies: 1
Views: 204

Re: [Beginner] A musical alarm + turning the lights on in the morning?

A Raspberry Pi Starter Kit would be one good way of getting to your idea.
by Idahowalker
Sat Dec 08, 2018 7:29 pm
Forum: Automation, sensing and robotics
Topic: HELP - Stewart Platform
Replies: 3
Views: 551

Re: HELP - Stewart Platform

I have made a XY stabilized platform with a LIDAR scanner sitting on top of the platform. I found the RPi is great at processing data but trying to get the RPi to process data and maintain a level platform plus other stuff... Eh, better to let something like an Arduino MEGA or DUE do the heavy lifti...
by Idahowalker
Sat Dec 08, 2018 7:06 pm
Forum: Python
Topic: Python stops Sending to Arduino
Replies: 2
Views: 385

Re: Python stops Sending to Arduino

The Python code? I know, not a Arduino forum but the Arduino code? I take it you are using level shifters of some sort between the RPi and Mega? I have ran a RPi to Mega serial com app that sent a cht load of data back and forth for months at a time, so I know its possible. I now run a RPi to DUE ap...

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