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by Ednixon
Mon Jan 14, 2019 12:31 am
Forum: C/C++
Topic: loop speed vs repeated statements
Replies: 2
Views: 454

loop speed vs repeated statements

How does the execution time compare between a FOR loop with incrementing arguments, and repeating the code over and over? Looping certainly be the preferred approach, but would it run any faster? Specifically, I have 3 IF statements that need to repeated about 50 times with changing arguments each p...
by Ednixon
Wed Oct 11, 2017 3:14 pm
Forum: General discussion
Topic: IR remote kit
Replies: 1
Views: 500

IR remote kit

Several of the commonly available IR remote kits come with a multi-key remote, a sensor, and another LED which may be mounted to a small circuit board. Is this just an additional IR sender in case you don't want to use the hand-held pad?
by Ednixon
Fri May 26, 2017 1:15 am
Forum: C/C++
Topic: 23017 programming
Replies: 4
Views: 620

23017 programming

I'm using a Pi V3 to communicate over I2C with a couple of 23017 expanders through wiringPi, and a C program. All I'm doing is using the outputs of the 23017s to turn on/off LEDs but they behave unpredictably. Sometime perfect, other times only some of the LED come on/off as they should. My first st...
by Ednixon
Wed Mar 01, 2017 9:54 pm
Forum: Advanced users
Topic: kill rpi C process
Replies: 1
Views: 550

kill rpi C process

Rpi3 with Raspbian, C program I have a C program which is autostarted by an entry in rc.local. This works fine. But on occasion I need ti interrupt/stop it. CTRL-C or CTRL-X do nothing. Ideally I need to ssh over network, open a terminal window and kill it from there. But neither ps -a or ps -all sh...
by Ednixon
Wed Mar 01, 2017 4:00 am
Forum: Advanced users
Topic: autorun on startup
Replies: 1
Views: 397

autorun on startup

I have had success with the rc.local method. But I see suggestions to be sure the program (in C) runs in the background by using the &. Why is it advisable to have it running in the background?
<ED>
by Ednixon
Fri Feb 03, 2017 5:18 pm
Forum: Advanced users
Topic: power connection to pi
Replies: 4
Views: 935

Re: power connection to pi

Thanks guys. That covers it for me.
I have now devised a custom micro USB plug with a right angle that will avoid the obstacles so I'll probably use that approach. But I'll definitely make note of these other suggestions.
by Ednixon
Thu Feb 02, 2017 9:35 pm
Forum: Advanced users
Topic: power connection to pi
Replies: 4
Views: 935

power connection to pi

I'm using an Rpi 2B embedded within the device it controls, and I have a space problem down where the micro USB power connector would plug in. Is there any other accessible contact point I could connect or solder to to bring in the +5V? I see the +5V pin on the GPIO port but I can't detect continuit...
by Ednixon
Tue Jan 03, 2017 3:24 am
Forum: General discussion
Topic: Rpi3 won't boot
Replies: 13
Views: 3930

Re: Rpi3 won't boot

Thanks. Indeed the power supply can be a trouble item. Red light did not blink. Never saw green at all. However - to you and all the other respondents on this issue - I eventually got the Pi3 to work properly. Thank you all for your suggestions. It required a complete rebuild of the SD card - format...
by Ednixon
Sun Jan 01, 2017 10:00 pm
Forum: General discussion
Topic: Rpi3 won't boot
Replies: 13
Views: 3930

Re: Rpi3 won't boot

Thank you. That's about what I'd decided to try. Faulty Pi is possible - this is brand new right of the box with no operational history that I know of.
by Ednixon
Sun Jan 01, 2017 9:12 pm
Forum: General discussion
Topic: Rpi3 won't boot
Replies: 13
Views: 3930

Re: Rpi3 won't boot

Sorry. Got several things mixed up. So starting over.. System info: OS info "name": "Raspbian", "version": "jessie", "release_date": "2015-11-21", "kernel": "4.1", "description": "A community-created port of Debian jessie, optimised for the Raspberry Pi", "url": "http://www.raspbian.org/", "username...
by Ednixon
Sun Jan 01, 2017 6:23 pm
Forum: General discussion
Topic: Rpi3 won't boot
Replies: 13
Views: 3930

Re: Rpi3 won't boot

Did the update/upgrade, didn't see anything different. Still comes up to the multicolor opening screen and stops there.
And the LED is green not blue on the V2. Indicates some kind of activity. I never see that LED do anything on the 3.
by Ednixon
Sun Jan 01, 2017 4:49 pm
Forum: General discussion
Topic: Rpi3 won't boot
Replies: 13
Views: 3930

Re: Rpi3 won't boot

No blue? Well it looks blue to my old eyes. Maybe it's green. Right next to the red that indicates power on. On my 2B+ that lLED flashes when it's reading the SD card. Or so it appears. The same LED appears to be on the 3 but never comes on.
by Ednixon
Sun Jan 01, 2017 3:34 pm
Forum: General discussion
Topic: Rpi3 won't boot
Replies: 13
Views: 3930

Re: Rpi3 won't boot

Thanks guys. OK on the slot thing, but it did seem suspicious.
An update was done fairly recently (couple of weeks maybe) but I'll do it again.
Also- I have no blue light at all. Should I see one?

So I guess what we're saying here is that I should be able to swap SD cards?
by Ednixon
Sun Jan 01, 2017 5:36 am
Forum: General discussion
Topic: Rpi3 won't boot
Replies: 13
Views: 3930

Rpi3 won't boot

I have a Rpi V2 B+ that works fine. I recently acquired an Rpi3. Is there any obvious reason this unit would not boot and run with the working SD card from the first unit? This is a brand new Rpi3. Color splash screen comes up but then acts like it doesn't see the SD card. The card is not corrupt. I...
by Ednixon
Thu Dec 29, 2016 5:39 am
Forum: C/C++
Topic: WiringPI and Geany
Replies: 5
Views: 4370

Re: WiringPI and Geany

The previous reply says to put -lWiringpi in the build command. But can I put 2 or more libraries in that line? What is the proper form to put multiple libraries in that line?
by Ednixon
Mon Dec 12, 2016 2:36 am
Forum: General discussion
Topic: C with Geany
Replies: 1
Views: 409

C with Geany

In Geany there is a provision in the compile and build commands to enter a statement. like -lbcm2835. How do you enter others if you need more than one?
Also is there another way to do this - like in a program statement line?
by Ednixon
Tue Mar 29, 2016 5:29 pm
Forum: General discussion
Topic: I/O extender with Python
Replies: 1
Views: 308

I/O extender with Python

Need a little help with some Python code. All I need to do is turn on and off the I/O (output) pins on a couple of 23016 chips with Python on I2C bus. Can anyone point me toward some examples please... Also - I'll be hard wiring to set the address lines to chip 0 and 1 but how is that designated in ...
by Ednixon
Wed Jan 27, 2016 5:58 pm
Forum: General discussion
Topic: 32 port expander with Python
Replies: 3
Views: 591

32 port expander with Python

For this product ... http://www.ebay.com/itm/Raspberry-Pi-Infinity-Cascade-RPI-GPIO-Expansion-Board-IO-Extend-Adapter-Module-/281658925086?hash=item41942e201e:g:G7IAAOSwv0tVKCGf How do you address the ports from Python? When you plug this on to the Rpi, does an output instruction to port 1 now go to...
by Ednixon
Wed Jan 27, 2016 5:56 pm
Forum: General discussion
Topic: Rpi io expander
Replies: 2
Views: 334

Re: Rpi io expander

Great - thanks. That's what I needed.
by Ednixon
Wed Jan 27, 2016 5:08 pm
Forum: General discussion
Topic: Rpi io expander
Replies: 2
Views: 334

Rpi io expander

Re this product ... http://www.ebay.com/itm/Raspberry-Pi-Infinity-Cascade-RPI-GPIO-Expansion-Board-IO-Extend-Adapter-Module-/281658925086?hash=item41942e201e:g:G7IAAOSwv0tVKCGf Does anyone know the logic-true current sourcing capability of these ports? Or - is there a source for a data sheet for the...
by Ednixon
Sun Jan 24, 2016 4:19 am
Forum: General discussion
Topic: infinity 32 i/o expander
Replies: 3
Views: 541

Re: infinity 32 i/o expander

by Ednixon
Fri Jan 22, 2016 3:46 pm
Forum: General discussion
Topic: infinity 32 i/o expander
Replies: 3
Views: 541

infinity 32 i/o expander

This is commonly set forth as an I/O expander, but can the ports (some) be configured as input? Some comments seen to indicate not.
by Ednixon
Wed Jan 20, 2016 11:25 pm
Forum: General discussion
Topic: i/o expansion board
Replies: 1
Views: 316

i/o expansion board

Need to program a bunch of LEDs to go on and off using gpio expansion board. I have the simple cascade 32port expansion board which is supposed to use the IIC bus. IIC is enabled. Progamming in Python - how do I control the new ports? What syntax do I need to turn on LED1, turn off LED1, then then o...

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