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by DougieLawson
Thu Jan 17, 2019 9:36 pm
Forum: Troubleshooting
Topic: Rpi3 hangs after 3 hours
Replies: 9
Views: 120

Re: Rpi3 hangs after 3 hours

Not tainted 4.9.61-v7+ #1049
Your kernel is 142 updates behind the current leading edge (hacker's paradise) rpi-update version. It's about 130 updates behind the current stable kernel. You really want to think about doing an upgrade so that you're not re-discovering known and fixed bugs.
by DougieLawson
Thu Jan 17, 2019 9:30 pm
Forum: Troubleshooting
Topic: New download image, eth0 is not finding an IP address.
Replies: 15
Views: 159

Re: New download image, eth0 is not finding an IP address.

Try a factory fresh SDCard and Raspbian Stretch 2018-11-13 written to it with Etcher.
by DougieLawson
Thu Jan 17, 2019 8:28 pm
Forum: Networking and servers
Topic: Some dhcpcd stuff still runs after a purge
Replies: 2
Views: 42

Re: Some dhcpcd stuff still runs after a purge

You'll need to reboot after making that kind of radical change to the default networking set-up.
by DougieLawson
Thu Jan 17, 2019 8:26 pm
Forum: Troubleshooting
Topic: New download image, eth0 is not finding an IP address.
Replies: 15
Views: 159

Re: New download image, eth0 is not finding an IP address.

1. WiFi WILL NOT work until you set the country code. rfkill will disable it. 2. Ethernet not getting an address is usually the sign of a cable fault. 3. In all cases if your power supply is too weedy then networking is the first thing to fail. RPi 3B/3B+ needs 5.1V @ 2.5A (which is, curiously, exac...
by DougieLawson
Thu Jan 17, 2019 6:39 pm
Forum: Troubleshooting
Topic: New download image, eth0 is not finding an IP address.
Replies: 15
Views: 159

Re: New download image, eth0 is not finding an IP address.

Any address in 169.254.0.0/16 is a link-local address assigned at random by the interface. It means your machine can't reach a DHCP server.

https://en.wikipedia.org/wiki/Link-local_address
by DougieLawson
Thu Jan 17, 2019 12:57 pm
Forum: Java
Topic: SPI read and write fuction
Replies: 1
Views: 32

Re: SPI read and write fuction

Lots of examples at: https://github.com/Pi4J/pi4j/tree/maste ... /main/java use SPI.

What sensor are you trying to use?
by DougieLawson
Thu Jan 17, 2019 12:53 pm
Forum: Java
Topic: Desktop indicators bleed through JavaFX
Replies: 4
Views: 69

Re: Desktop indicators bleed through JavaFX

Why not just delete that widget from the taskbar.
by DougieLawson
Thu Jan 17, 2019 12:56 am
Forum: Networking and servers
Topic: Send data from raspberry pi to another raspberry pi
Replies: 2
Views: 74

Re: Send data from raspberry pi to another raspberry pi

Use an MQTT bridge.

That could be a python program that subscribes to one topic on one MQTT broker and publishes on an identical topic on your CloudMQTT broker.

Mosquitto can do that with some funky configuration directives.
by DougieLawson
Wed Jan 16, 2019 10:27 pm
Forum: General discussion
Topic: switching to 64bit kernel
Replies: 6
Views: 200

Re: switching to 64bit kernel

Best option for the best supported 64-bit OS is viewtopic.php?f=54&t=188448

Note: it is not supported or blessed by RPT/RPF it's the work of a dedicated hobbyist.
by DougieLawson
Wed Jan 16, 2019 10:23 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Can an LCD share the SPI bus with another device
Replies: 3
Views: 235

Re: Can an LCD share the SPI bus with another device

Try it, it's the only way you'll find out for sure.
by DougieLawson
Wed Jan 16, 2019 12:25 am
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: Can an LCD share the SPI bus with another device
Replies: 3
Views: 235

Re: Can an LCD share the SPI bus with another device

There's two SPI buses and five chip select (chip enable) pins on the 40 pin header. You can have five SPI devices.

https://pinout.xyz/pinout/spi
by DougieLawson
Tue Jan 15, 2019 6:04 pm
Forum: Weather station
Topic: Send data with mqtt
Replies: 8
Views: 769

Re: Send data with mqtt

Your choice.
by DougieLawson
Mon Jan 14, 2019 3:06 pm
Forum: Troubleshooting
Topic: Can hardware be the cause of what looks a like software bug?
Replies: 3
Views: 313

Re: Can hardware be the cause of what looks a like software bug?

Bizarre hardware things are usually due to a weedy power supply that isn't up to the job.
by DougieLawson
Mon Jan 14, 2019 8:53 am
Forum: Advanced users
Topic: config.txt file kernel reading procedure
Replies: 7
Views: 684

Re: config.txt file kernel reading procedure

2) No. and 3) No.

That stuff is proprietary, it's undocumented. You won't get any details beyond what's discussed on viewforum.php?f=72
by DougieLawson
Mon Jan 14, 2019 1:29 am
Forum: HATs and other add-ons
Topic: Pi TV Hat questions
Replies: 4
Views: 1601

Re: Pi TV Hat questions

Did anybody discover whether multiple TV hats can be connected to the GPIO of the same Pi? They can't work because both would use the same SPI chip select/chip enable pin unless you can change the hardware (which isn't possible for a hobbyist). If you look in https://github.com/raspberrypi/linux/bl...
by DougieLawson
Mon Jan 14, 2019 1:25 am
Forum: Advanced users
Topic: Can no longer compile kernel modules on Raspbian with RPi 1B
Replies: 3
Views: 406

Re: Can no longer compile kernel modules on Raspbian with RPi 1B

The kernel headers package seems to follow the raspberrypi-kernel package (current stable kernel). My systems are always a long way ahead of that (some are running 4.19 with BRANCH=next rpi-update). I like rpi-source as it's a simple way to get something that seems to work more often than not.
by DougieLawson
Sun Jan 13, 2019 10:09 pm
Forum: Advanced users
Topic: Can no longer compile kernel modules on Raspbian with RPi 1B
Replies: 3
Views: 406

Re: Can no longer compile kernel modules on Raspbian with RPi 1B

Try this: https://github.com/notro/rpi-source/wiki rpi-source will get you a current kernel source tree that matches your running kernel. I created ~/module.c and ~/Makefile from your samples and they worked OK. [email protected]:~ # vi module.c [email protected]:~ # vi Makefile [email protected]:~ # make make -C ...
by DougieLawson
Sun Jan 13, 2019 7:27 pm
Forum: General discussion
Topic: Problem with microSD and OMSC installation
Replies: 3
Views: 81

Re: Problem with microSD and OMSC installation

Try another, known good, SDCard.
by DougieLawson
Sun Jan 13, 2019 5:57 pm
Forum: General discussion
Topic: Raspberry Pi 3 B+ stopped working after update.
Replies: 18
Views: 420

Re: Raspberry Pi 3 B+ stopped working after update.

With NOOBS /dev/sda2 is a logical partition container not a valid partition.

You need to fsck /dev/sda1 /dev/sda5 /dev/sda6 and /dev/sda7.
by DougieLawson
Sun Jan 13, 2019 5:47 pm
Forum: Troubleshooting
Topic: PHP MySQL query, query.
Replies: 1
Views: 49

Re: PHP MySQL query, query.

<?php $con=mysqli_connect("localhost","username_goes_here","user_password_goes_here",db_name_here"); $sql_stmt = "SELECT MAX('temp') AS max_temp FROM 'readings';"; $select_query = sprintf($sql_stmt); if (mysqli_connect_errno()) { echo "Failed to connect to MySQL: " . mysqli_connect_error(); } $resu...
by DougieLawson
Sun Jan 13, 2019 3:34 pm
Forum: General discussion
Topic: Raspberry Pi 3 B+ stopped working after update.
Replies: 18
Views: 420

Re: Raspberry Pi 3 B+ stopped working after update.

How are you failing to see the umount command?

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