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by myoung008
Sat Feb 04, 2017 4:17 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: RPi3 won't boot with I2C connected
Replies: 0
Views: 382

RPi3 won't boot with I2C connected

I'm having a problem with i2c, and specifically GPIO3 being held low too long at boot. I have several i2c devices (MCP23017s) connected to i2c1 over a bus that can be up to 25 feet long. I've used the TI P82B715 extender to accomplish this, so the local side bus is only an inch or so on each PCB. Th...
by myoung008
Sun Feb 28, 2016 9:07 pm
Forum: C/C++
Topic: can't find i2c-0 GPIO pins any more
Replies: 51
Views: 5378

Re: can't find i2c-0 GPIO pins any more

@davenull - Please listen to what everyone else is telling you about the way you've gone about this topic. My reluctance to continue helping in an earlier post -- being tempted to bow out was due to that as well. Nobody cares that you (or I for that matter) are using i2c-0. They are trying to expres...
by myoung008
Sat Feb 27, 2016 6:40 pm
Forum: C/C++
Topic: can't find i2c-0 GPIO pins any more
Replies: 51
Views: 5378

Re: can't find i2c-0 GPIO pins any more

Ah, 0x60 on each of your buses. I read that wrong, I thought you meant ALL i2c buses (like a host address or something). At any rate, the code examples I sent will work just fine opening both devices simultaneously on different buses. I was looking at the repo on github, but I just checked the offic...
by myoung008
Sat Feb 27, 2016 6:09 pm
Forum: C/C++
Topic: can't find i2c-0 GPIO pins any more
Replies: 51
Views: 5378

Re: can't find i2c-0 GPIO pins any more

If the code works fine on i2c-1 then ignore that part of what I said. My knowledge of i2c is not 100%. The two ifs wrapping open() and ioctl() are there to trap any errors opening the device. If your config or kernel gets changed and i2c-0 disappears the first one fails. If you don't run with the ap...
by myoung008
Sat Feb 27, 2016 5:06 pm
Forum: C/C++
Topic: can't find i2c-0 GPIO pins any more
Replies: 51
Views: 5378

Re: can't find i2c-0 GPIO pins any more

instead of: if ((fd = wiringPiI2CSetup (0x60) ) < 0) { fprintf (stderr, "Can't open RTC: %s\n", strerror (errno)) ; exit (EXIT_FAILURE) ; } try #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <sys/ioctl.h> #include <linux/i2c-dev.h> if ((fd = open ("/dev/i2c-0", O_RDWR)) < 0...
by myoung008
Fri Feb 26, 2016 6:28 pm
Forum: C/C++
Topic: can't find i2c-0 GPIO pins any more
Replies: 51
Views: 5378

Re: can't find i2c-0 GPIO pins any more

@davenull: I'm tempted just to bow out, but I'll try one more time. WiringPi is aiming to fill the needs of the masses, and that includes HATs. That being said, i2c is dead-simple to use. All you would need to do is open the appropriate bus for each device, then pass the appropriate one to the read/...
by myoung008
Fri Feb 26, 2016 1:49 am
Forum: C/C++
Topic: can't find i2c-0 GPIO pins any more
Replies: 51
Views: 5378

Re: can't find i2c-0 GPIO pins any more

I use i2c-0 for non-HAT purposes. In config.txt: dtparam=i2c0=on dtparam=i2c1=on force_eeprom_read=0 bcm_2708.vc_i2c_override=1 This is for a bcm2708/devicetree kernel, not the newer bcm2835. I don't know if it would make a difference. Anyway, both buses show up and work fine. I'm using a Pi 2B, but...
by myoung008
Mon Jul 13, 2015 4:52 am
Forum: General discussion
Topic: QT application running reg
Replies: 51
Views: 7720

Re: QT application running reg

gitorious is down. They are in the middle of migrating data to the Internet Archive, at which point you should be able to clone the repository again.
by myoung008
Sun Jul 12, 2015 6:49 am
Forum: Beginners
Topic: Raspberry Pi 2: Nginx will not bind [SOLVED]
Replies: 2
Views: 1225

Re: Raspberry Pi 2: Nginx will not bind

See what process is using the ports:

Code: Select all

sudo netstat -lpn
I've seen 'restart' not work on nginx in the past, try 'stop' and 'start' instead.
by myoung008
Fri Jul 10, 2015 8:39 pm
Forum: Troubleshooting
Topic: How to connect raspberry internally
Replies: 5
Views: 1014

Re: How to connect raspberry internally

@gamaxwell: Your problem is a little different, as you can get to the outside world in general. In your case I'd wait a little while while and try again. Failing that, you might want to post a copy of the actual errors you are getting as well. It may be slightly different than OP and give a better i...
by myoung008
Wed Jul 08, 2015 9:59 pm
Forum: Networking and servers
Topic: Pi 2 & Synology box
Replies: 8
Views: 2323

Re: Pi 2 & Synology box

CCoates wrote:sudo mount -t nfs 192.168.0.17:/volume1/kodi /mnt/kodi
Add the following to your /etc/fstab:

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192.168.0.17:/volume1/kodi /mnt/kodi nfs defaults 0 0
That may or may not be what you're actually looking for, but it is equivalent to your mount command.
by myoung008
Wed Jul 08, 2015 4:58 pm
Forum: Troubleshooting
Topic: How to connect raspberry internally
Replies: 5
Views: 1014

Re: How to connect raspberry internally

You really haven't given enough information, but as a wild guess, try this:

Code: Select all

sudo route add default gw 10.42.1.1
echo nameserver 10.42.1.1 | sudo tee -a /etc/resolv.conf
If this fixes it, it will only work until the next reboot.
by myoung008
Mon Jul 06, 2015 5:05 am
Forum: Advanced users
Topic: NFS Boot with fall back to local image
Replies: 7
Views: 1012

Re: NFS Boot with fall back to local image

I don't know of any tutorials, but it's the way you switch from an initrd to the real root filesystem. Most linux live CD/DVDs will have scripts in their initrds that you can look at/modify to your needs.
by myoung008
Sat Jul 04, 2015 5:52 pm
Forum: Troubleshooting
Topic: PI2 ethernet packet loss
Replies: 9
Views: 992

Re: PI2 ethernet packet loss

I don't recall having any packet loss to speak of on any version of the Raspbian, or any other Pi distro for that matter. I've not seen many users having that issue, either.
by myoung008
Sat Jul 04, 2015 3:41 pm
Forum: Troubleshooting
Topic: PI2 ethernet packet loss
Replies: 9
Views: 992

Re: PI2 ethernet packet loss

I'd try pinging between several of your local hosts not on the ESXi box to see if you can tie it to that one machine. If so, then it's probably in the network config for the hypervisor/VMs on that box. I'm afraid I won't be of much help there, I've not used any VMWare product in about 10 years.
by myoung008
Fri Jul 03, 2015 7:59 pm
Forum: Troubleshooting
Topic: PI2 ethernet packet loss
Replies: 9
Views: 992

Re: PI2 ethernet packet loss

My network topology is similar to yours, only a switch connected to the main router and everything else (including more switches for other parts of the house) coming off that. I don't have any issues with pings to/from any host to/from any other. I'm using a mix of "dumb" switches and a TP-Link TL-S...
by myoung008
Fri Jul 03, 2015 5:27 pm
Forum: Troubleshooting
Topic: PI2 ethernet packet loss
Replies: 9
Views: 992

Re: PI2 ethernet packet loss

I would start with the settings on the Netgear switch. If there isn't something obvious, I'd start by locking the port to 100Mbit, Full Duplex, MDI. I'm guessing here but it seems like it may be continuously trying to renegotiate to gigabit speeds or something like that.
by myoung008
Fri Jul 03, 2015 6:36 am
Forum: Networking and servers
Topic: MySQL 5.6 on Pi 2
Replies: 4
Views: 1216

Re: MySQL 5.6 on Pi 2

MariaDB makes a great replacement for MySQL and is stable. It's available for Raspbian Jessie (MariaDB 10.0 ~= Mysql 5.6). It's probably available somewhere for Raspbian Wheezy as well. I've run it on a few Pis and other arm boards with great stability. I'm not using Raspbian for those machines, but...
by myoung008
Fri Jul 03, 2015 6:14 am
Forum: Other programming languages
Topic: HTML & PHP
Replies: 12
Views: 2543

Re: HTML & PHP

This is what you were wanting your original code to do. Note that the code gets called multiple times. The first time the action is not set so the php part is ignored and it puts out the form. Clicking a button submits the form with action set. The PHP writes to the file and then sends the form out ...
by myoung008
Thu Jul 02, 2015 1:57 am
Forum: Advanced users
Topic: NFS Boot with fall back to local image
Replies: 7
Views: 1012

Re: NFS Boot with fall back to local image

You could create a very small root file system that attempts to mount the nfs first, and if it fails it mounts the real local root, then pivot_root. The kernel command line would point to the small filesystem.
by myoung008
Mon Jun 22, 2015 11:12 pm
Forum: C/C++
Topic: C++ IDE
Replies: 6
Views: 3000

Re: C++ IDE

I use Qt Creator for all of my C and C++ projects. It works well whether or not you're using Qt in your project. It automates a lot of the build process with cmake and has integrated debugging and valgrind. It does pretty good with code completion too.
by myoung008
Mon Jun 22, 2015 4:56 pm
Forum: Troubleshooting
Topic: systemd high cpu usage
Replies: 23
Views: 7144

Re: systemd high cpu usage

Sslh is logging each new connection. I don't see an option for sslh to reduce logging. You may be able to filter it with journald. Two possible reasons for the excessive logs: If you can NOT connect to your final https service correctly: You may still be looping your connections with your sslh confi...
by myoung008
Thu Jun 18, 2015 9:36 pm
Forum: Pidora / Fedora
Topic: Does anyone know why this won't boot?
Replies: 6
Views: 3213

Re: Does anyone know why this won't boot?

Where does it get hung up?

No display at all?
Rainbow screen?
After kernel init?
Userland setup?

As for the cmdline.txt question, post output of:

Code: Select all

sudo blkid /dev/sdc*
by myoung008
Thu Jun 18, 2015 9:33 pm
Forum: General discussion
Topic: How to synchronize multiple video displays?
Replies: 26
Views: 18922

Re: How to synchronize multiple video displays?

You could try Falcon Pi Player. It's designed to run Christmas light shows, but also supports video and multiple Pi's in sync.

http://falconchristmas.com/forum/index. ... d,8.0.html
by myoung008
Thu Jun 18, 2015 8:56 pm
Forum: Troubleshooting
Topic: systemd high cpu usage
Replies: 23
Views: 7144

Re: systemd high cpu usage

Code: Select all

systemctl list-unit-files
You may also want:

Code: Select all

systemctl enable xxxxx
systemctl disable xxxxx
systemd-analyze blame
systemd-analyze plot > bootchart.svg
After that last one, open bootchart.svg in a svg capable image viewer.

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