Go to advanced search

by tempest766
Thu Feb 21, 2019 5:01 pm
Forum: General discussion
Topic: Ban OPENCAS mirrors [solved]
Replies: 22
Views: 1446

Re: Ban OPENCAS mirrors

"please don't offend china"??? why, will my chinese made sneakers suddenly blow up because I said something bad about them? To be blunt, no, I'm not going to avoid offending someones feelings about a regime with a proven history of both state and corporate espionage, and terrible human rights issues...
by tempest766
Thu Feb 21, 2019 4:51 pm
Forum: General discussion
Topic: Computer vision method
Replies: 3
Views: 219

Re: Computer vision method

Figure it out. That's what an assignment is.
by tempest766
Thu Feb 21, 2019 3:37 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: RS485 with UART and pyserial
Replies: 5
Views: 2792

Re: RS485 with UART and pyserial

For RS485 communication the sender / receiver has to by switched in either send or receive mode. This is done normally by an additional output pin. The board I have doesn't do this and switches between send and receive depending on the state of TX. I think this is somewhat strange but seems to work...
by tempest766
Thu Feb 21, 2019 3:30 am
Forum: General discussion
Topic: Portable connection
Replies: 1
Views: 103

Re: Portable connection

web search "multicast"
by tempest766
Thu Feb 21, 2019 3:27 am
Forum: General discussion
Topic: Computer vision method
Replies: 3
Views: 219

Re: Computer vision method

yes. openCV should work fine for that application.

Get busy watching the openCV tutorials!
by tempest766
Thu Feb 21, 2019 3:22 am
Forum: General discussion
Topic: Ban OPENCAS mirrors [solved]
Replies: 22
Views: 1446

Re: Ban OPENCAS mirrors

Binary code distributed from within China? What could possibly go wrong?
by tempest766
Wed Feb 20, 2019 2:04 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: SPI: double words when faster than 32 MHz
Replies: 4
Views: 626

Re: SPI: double words when faster than 32 MHz

My question is: why and what can I do to prevent this? I am aware that speeds above 32 MHz are said to be unstable, but I imagined that would be because of the more difficult hardware setup (impedance matching, length of traces, etc.). I think you've answered your own question, then made some asser...
by tempest766
Wed Feb 20, 2019 2:01 am
Forum: Troubleshooting
Topic: Raspberry Pi Zero W gets really hot but does not turn on.
Replies: 3
Views: 227

Re: Raspberry Pi Zero W gets really hot but does not turn on.

visible damage is not an indicator. you toasted it.
by tempest766
Wed Feb 20, 2019 1:58 am
Forum: HATs and other add-ons
Topic: Tips for soldering GPIO
Replies: 8
Views: 1142

Re: Tips for soldering GPIO

because no one does that. you get a female ribbon cable connector that fits over the header.
by tempest766
Mon Feb 18, 2019 6:47 pm
Forum: Troubleshooting
Topic: pi-packages requires enabled user root
Replies: 1
Views: 114

Re: pi-packages requires enabled user root

Don't be a victim of the "there should be no root" brainwashing. Not doing work as root is a prime axample of a good best-practice that has become a religion. Take it in context! It's not like you're managing a UNIX box for the NORAD, where a misplaced command might give a false missle launch indica...
by tempest766
Fri Feb 15, 2019 1:10 am
Forum: Python
Topic: Preventing RPi.GPIO access conflicts
Replies: 4
Views: 296

Re: Preventing RPi.GPIO access conflicts

Yes, and I noted I could do that, or use pigpiod as Dougie suggests, and it does seem it is the best one can achieve with things how they are. Using a daemon doesn't entirely help though if anything else is running which doesn't use that to indicate it is using some specific GPIO. It seems there is...
by tempest766
Thu Feb 14, 2019 3:53 am
Forum: Python
Topic: Preventing RPi.GPIO access conflicts
Replies: 4
Views: 296

Re: Preventing RPi.GPIO access conflicts

create a daemon process that manages the GPIO and make the user applications call the service through that daemon. this is a common pattern to manage single access resources.
by tempest766
Wed Feb 13, 2019 6:21 am
Forum: Beginners
Topic: Is it possible to only use a specific part of the screen?
Replies: 4
Views: 130

Re: Is it possible to only use a specific part of the screen?

no, because the default desktop will use the whole screen. you have to throw out the desktop and create individual X11 client applications in the screen areas that interest you. The desktop itself is an X11 client app, but hacking it to only use a specific portion of the screen would be non-trivial.
by tempest766
Tue Feb 12, 2019 10:50 pm
Forum: Compute Module
Topic: CM3 - UART baudrate reverted to 115 200
Replies: 7
Views: 1925

Re: CM3 - UART baudrate reverted to 115 200

perhaps you're overreaching on what the SOC UART is reliably capable of at the hardwired GPU clock speed? it may work until the FIFO hiccups and then drop back to a sane speed.
by tempest766
Tue Feb 12, 2019 10:22 pm
Forum: Beginners
Topic: Login to raspberry pi via USB-TTL cable
Replies: 1
Views: 77

Re: Login to raspberry pi via USB-TTL cable

assuming you followed the directions in the guide correctly, I'd suggest the following: 1) make sure your usb/uart cable is connected to the right pins for transmit and receive and ground 2) forget screen and install a better dedicated terminal program on the linux box. I exclusively use minicom. di...
by tempest766
Tue Feb 12, 2019 10:13 pm
Forum: Beginners
Topic: Is it possible to only use a specific part of the screen?
Replies: 4
Views: 130

Re: Is it possible to only use a specific part of the screen?

it's your screen. you can put whatever you want, wherever you want on it. the open ended nature of your question prohibits anyone telling you how to do it thought...but yes, it's possible. We did that sort of thing all the time in creating lcd instrument displays for flight simulators. the bezel cov...
by tempest766
Tue Feb 12, 2019 9:40 pm
Forum: HATs and other add-ons
Topic: RS232 without using GPiO help please?
Replies: 10
Views: 1005

Re: RS232 without using GPiO help please?

yeah. the contact function seems to be inactive. I'm a Buell guy. Have a 2008 Uly-xt, and grew up in the same county as Eric Buell. A couple years ago switched to a 2015 Yammee FJR, but keep the Uly running as a hooligan bike. Look up Kent Dorfman on facebook and find the image of the baby smoking t...
by tempest766
Mon Feb 11, 2019 7:44 pm
Forum: General discussion
Topic: Send IP packets Raspberry boards
Replies: 2
Views: 179

Re: Send IP packets Raspberry boards

recording your voice is a soundcard mic-in function. at least on the 3b units I have there is no audio input capability, so yes, you'd need a daughterboard that provides audio-in. many ways to handle message acknowledgement of IP or TCP. if you use UDP then the receiver would need to send a datagram...
by tempest766
Mon Feb 11, 2019 7:18 pm
Forum: Automation, sensing and robotics
Topic: Ultrasonic sensor and voltage division
Replies: 19
Views: 1418

Re: Ultrasonic sensor and voltage division

you've got it backwards, which isn't surprising. Since electrons are negatively charged, people assume that (-) is the supply of electrons...but it's actually the other way around. "echo" is a supply of electrons that want to move to ground (-), being pushed at some voltage potential (5v). Your diag...
by tempest766
Mon Feb 11, 2019 6:50 pm
Forum: HATs and other add-ons
Topic: RS232 without using GPiO help please?
Replies: 10
Views: 1005

Re: RS232 without using GPiO help please?

On a note to who it was that mentioned DTE etc. We only need 3 wire grnd, rx and tx and can use xon/xoff if needed in the synth firmware. What is the best reference for how linux identifies and updates attached hardware like the usb serial port? at least you said "3 wire" and didn't do the "we don'...
by tempest766
Mon Feb 11, 2019 4:33 am
Forum: Troubleshooting
Topic: Raspberry is not detecting extra space from new SD card
Replies: 2
Views: 137

Re: Raspberry is not detecting extra space from new SD card

what does sudo fdisk -l /dev/sda show? did the expand function expand the partition to use the whole disk?
by tempest766
Mon Feb 11, 2019 4:28 am
Forum: General discussion
Topic: How to stream the raspberry pi screen to an rtmp server using ffmpeg?
Replies: 2
Views: 616

Re: How to stream the raspberry pi screen to an rtmp server using ffmpeg?

software 264 encoding through the pi is going to be extremely slow. no way you will be able to do it in real-time.
by tempest766
Mon Feb 11, 2019 4:23 am
Forum: General discussion
Topic: running python script on startup
Replies: 8
Views: 442

Re: running python script on startup

rc.local is an appropriate place to put startup jobs, but the systemd crowd will tell you to complicate matter by creating a custom service. you probably have to make sure the rc.local file has the excute bit set on it as well. jobs in rc.local wil run as superuser by default python is not a good la...
by tempest766
Sun Feb 10, 2019 9:03 pm
Forum: HATs and other add-ons
Topic: RS232 without using GPiO help please?
Replies: 10
Views: 1005

Re: RS232 without using GPiO help please?

The idea is to use a Pi zero as an old fashioned computer terminal in place of a laptop. The 'terminal' is to communicate with a home made synthesizer that an old school friend is designing and building. We're both getting on a bit and find getting to grips with operating system level stuff and ter...

Go to advanced search