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by liudr
Sat Jul 22, 2017 3:29 am
Forum: Automation, sensing and robotics
Topic: OK to remove power LED
Replies: 9
Views: 2081

Re: OK to remove power LED

What I am trying to do is to make an "OK to remove power LED". When the LED turns off, it is then OK to remove power. That's already there, the bootcode/firmware winks the green LED 10 times then it's OK to remove power. Thanks. Good to know for myself. I am making this for a data logger operator s...
by liudr
Sat Jul 22, 2017 3:23 am
Forum: Automation, sensing and robotics
Topic: USB serial adapter order
Replies: 7
Views: 2878

Re: USB serial adapter order

Understandable but in my experience the order will change. A different strategy would be to let your software try to figure out which ttyUSBx is connected to which port. Using the information in "/sys/bus/usb/devices/" maybe. [email protected]:~ $ ls /sys/bus/usb/devices/1-1.2:1.0 authorized bInterf...
by liudr
Thu Jul 20, 2017 6:06 pm
Forum: Beginners
Topic: RPi.GPIO question: to BOARD or to BCM?
Replies: 6
Views: 2372

Re: RPi.GPIO question: to BOARD or to BCM?

Well, there is a glitch. I am using adafruit I2C LCD plate so I guess there is a conflict in which pin naming mode I might use: BOARD and which one adafruit probably uses: BCM. I can't quite find where adafruit does the mode setting though.
by liudr
Thu Jul 20, 2017 5:47 pm
Forum: Beginners
Topic: RPi.GPIO question: to BOARD or to BCM?
Replies: 6
Views: 2372

RPi.GPIO question: to BOARD or to BCM?

I have never seriously played with RPI's GPIO since I use Arduino for IO until now. I just need a couple of buttons and LEDs so I don't waste an arduino for it. I looked at GPIO Zero and that seems to be for real beginners. So I am now considering RPi.GPIO and want some advice whether to go BOARD or...
by liudr
Thu Jul 20, 2017 5:44 pm
Forum: Beginners
Topic: to pi or not to pi
Replies: 10
Views: 1605

Re: to pi or not to pi

A number of years (or shall we say a number of pi revisions ago?) ago I developed a project on pi 1B using C/C++. It was a good project and a good amount of coding. I learned and now forgot how to daemonize my code for linux besides other libraries I had to use to straighten up the serial port to no...
by liudr
Thu Jul 20, 2017 4:08 pm
Forum: General discussion
Topic: [solution] Can't upgrade pyserial in latest raspbian distro
Replies: 3
Views: 860

Re: [solution] Can't upgrade pyserial in latest raspbian dis

Fair enough. I'll have to note to myself and others since the current stock pyserial is just too old to even have serial tools to identify ports, almost making it useless unless you know your port name ahead of time (like a very simple hobby project). I didn't know another debian version is coming o...
by liudr
Thu Jul 20, 2017 4:06 pm
Forum: Automation, sensing and robotics
Topic: USB serial adapter order
Replies: 7
Views: 2878

Re: USB serial adapter order

Thanks but that's what I wanted to avoid due to the likelihood of switching adapters (replacement for dead ones for example). I thought that there must be a definitive sequence the USB devices are enumerated, instead of somehow randomly enumerated.
by liudr
Thu Jul 20, 2017 4:04 pm
Forum: Beginners
Topic: to pi or not to pi
Replies: 10
Views: 1605

Re: to pi or not to pi

SurferTim, you answered your own question. There is no i2c connection between arduino and rpi so just the async serial where no master/slave relation exists. Interesting. There is a surferTim on arduino forum. I have some python code that communicates with arduino via serial port: https://liudr.word...
by liudr
Thu Jul 20, 2017 6:04 am
Forum: Beginners
Topic: to pi or not to pi
Replies: 10
Views: 1605

Re: to pi or not to pi

Make sure you check your I2C sensors for pullup resistors. Some sensor boards have 2K to 10K pullup resistors between SCL/SDA and 5V so you have to desolder them if you want to use the sensor boards on PI. How you connect depends on your comfort level. Like you said, you are comfortable with Arduino...
by liudr
Thu Jul 20, 2017 5:46 am
Forum: General discussion
Topic: Uart Driver for rasberry pi-3 or bcm235 Uart driver
Replies: 3
Views: 959

Re: Uart Driver for rasberry pi-3 or bcm235 Uart driver

If you can communicate with the gsm module using minicom then there is no need for any additional driver. Are you asking for example code instead of driver? This depends on the programming language you intend to use and the gps module's model may play a role too.
by liudr
Wed Jul 19, 2017 8:53 pm
Forum: Automation, sensing and robotics
Topic: OK to remove power LED
Replies: 9
Views: 2081

Re: OK to remove power LED

Thanks! I didn't know about this stuff until now. That's a pretty elegant solution. The feature seems to be used for signaling the power supply to shutdown. I can use this pin and an n-channel MOSFET to drive the LED ring on the push button. I wonder if the default setting is active_low or how to se...
by liudr
Wed Jul 19, 2017 6:19 pm
Forum: Automation, sensing and robotics
Topic: USB serial adapter order
Replies: 7
Views: 2878

USB serial adapter order

I have 4 USB serial adapters of the same kind connected to my RPI 3B. I figured out the following names were used in association with the actual ports. Just want to have more experienced people take a look to see if I made a mistake: https://liudr.files.wordpress.com/2017/07/usb-connection.png My go...
by liudr
Wed Jul 19, 2017 5:58 pm
Forum: Automation, sensing and robotics
Topic: OK to remove power LED
Replies: 9
Views: 2081

OK to remove power LED

What I am trying to do is to make an "OK to remove power LED". When the LED turns off, it is then OK to remove power. This is for a data logger. The operator will not be linux guru. I am just wondering, if I set up a GPIO pin with an n-channel MOSFET to turn on an LED by writing a LOW to it, then if...
by liudr
Tue Jul 18, 2017 6:15 pm
Forum: General discussion
Topic: TeamViewer IoT Developer Contest: Win up to EUR 5,000
Replies: 40
Views: 28317

Re: TeamViewer IoT Developer Contest: Win up to EUR 5,000

The file transfer is not implemented in this demo. If you initiate file transfer from the viewer side, say on a PC, it would not be able to list files on the host side.

The logo can't be minimized or sent to another desktop :)
by liudr
Tue Jul 18, 2017 5:36 pm
Forum: General discussion
Topic: TeamViewer IoT Developer Contest: Win up to EUR 5,000
Replies: 40
Views: 28317

Re: TeamViewer IoT Developer Contest: Win up to EUR 5,000

Haven't tried on RPI0 and don't yet own RPI0W. I am using it on my 3B. It's running very smoothly and I am currently using it as primary way to debug my python project. I can't stand the mouse handling in native raspbian when resolution is too high. Fortunately Teamviewer uses windows mouse handling...
by liudr
Tue Jul 18, 2017 5:16 pm
Forum: General discussion
Topic: [solution] Can't upgrade pyserial in latest raspbian distro
Replies: 3
Views: 860

[solution] Can't upgrade pyserial in latest raspbian distro

This is just for your information. If you are trying to use the latest distro of raspbian with pyserial for some serial port project, you may have come across this issue that regardless how you upgrade pyserial using pip3, your python3 will always call up the old pyserial 2.6 that came with the dist...
by liudr
Mon Jul 03, 2017 6:32 am
Forum: Beginners
Topic: Trying to understand interrupt for buttons.
Replies: 2
Views: 451

Trying to understand interrupt for buttons.

I am learning RPi.GPIO module for python to sense button pushes using interrupts. I was reading this tutorial from a few years back: http://raspi.tv/2013/how-to-use-interrupts-with-python-on-the-raspberry-pi-and-rpi-gpio-part-3 Apart from python2/3 issue on print, it works. But I was wondering about...
by liudr
Fri Feb 17, 2017 4:42 am
Forum: Beginners
Topic: 3B enterprise WPA?
Replies: 1
Views: 427

3B enterprise WPA?

I have not been up to date regarding RPI 3B enterprise WPA for a few months. Last time I checked the distribution didn't support it so I put mine on an ethernet port. Now I see someone using their pi on wifi so I want to ask if all I need to do is just upgrading the distribution to get mine on enter...
by liudr
Tue Nov 15, 2016 4:00 am
Forum: Beginners
Topic: clone sd card?
Replies: 27
Views: 50428

Re: clone sd card?

Like you said, it has nothing to do with the OP. You should start a new thread. And, I don't have an answer to your question. Sorry.
by liudr
Sun Oct 30, 2016 2:35 am
Forum: Off topic discussion
Topic: Joke involving rpi
Replies: 16
Views: 3362

Joke involving rpi

I placed a 2B in my 3B's retail paper box and gave it to someone else while saying:
2B, or not 2B!
by liudr
Sun Oct 30, 2016 2:32 am
Forum: General discussion
Topic: IS there a way to clone/make an exact copy of a SD card?
Replies: 6
Views: 3815

Re: IS there a way to clone/make an exact copy of a SD card?

The first reply missed the windows os you're using. I use a free software Paragon backup and recovery to back up my raspberry pi cards. Done dozen of times and a number or restores, no problem:

https://liudr.wordpress.com/2016/03/25/ ... pberry-pi/
by liudr
Fri Aug 26, 2016 8:29 pm
Forum: General discussion
Topic: Pi 2 resetting with rainbow screen
Replies: 4
Views: 883

Re: Pi 2 resetting with rainbow screen

The small rainbow block means your pi is not getting enough voltage. Do you have a decent andriod phone with an original charger or ask a friend that does? Try it with its original phone charger cable and see if you still get the small rainbow block. You tried several chargers and cables but I'm tel...
by liudr
Tue Aug 02, 2016 4:26 am
Forum: Beginners
Topic: Before I buy I'd like to make sure I'm up to the task
Replies: 9
Views: 1633

Re: Before I buy I'd like to make sure I'm up to the task

I like this display that comes with a clear case: http://www.banggood.com/3_5-Inch-TFT-LCD-Display-DIY-Acrylic-Case-For-Raspberry-Pi-BB-p-960194.html Works with my rpi 2 (haven't tested 3 but should work). The hard part is to get a temperature probe connected once you slap this display over the pi. ...
by liudr
Tue Aug 02, 2016 3:28 am
Forum: General discussion
Topic: Edit files on SD card
Replies: 22
Views: 31903

Re: Edit files on SD card

Paragon's free version is what I use. Auto mount the linux partition. Modified files copied files etc. No complaints. I don't know about paying $20 for small file changes that I make. If you're copying large video files, you may see some limitations. What is the limitation and will it matter on a su...
by liudr
Tue Aug 02, 2016 3:21 am
Forum: General discussion
Topic: Can we use windows Os and software in Raspberry Pi ?
Replies: 11
Views: 4917

Re: Can we use windows Os and software in Raspberry Pi ?

OP, If you want low-cost office computers, take a look at thin clients and mini-pcs. If you have keyboard and screen, take a look at this one (<150USD) and the like: http://www.newegg.com/Product/Product.aspx?Item=N82E16883800012&ignorebbr=1 If you want the screen as well, maybe get an Atom-based la...

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