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by knute
Sat Dec 04, 2021 3:41 am
Forum: Troubleshooting
Topic: How to get HDMI output on so I can set screen size without monitor
Replies: 2
Views: 134

How to get HDMI output on so I can set screen size without monitor

PI3B+ Current Bullseye KMS No monitor. How do I get it out of composite mode and into HDMI and then how do I get it to 1920x1080 so when I connect with VNC I get a 1920x1080 desktop? I tried every combination I could think of with hdmi_force_hotplug, hdmi_group and hdmi_mode.
by knute
Fri Dec 03, 2021 4:31 pm
Forum: Troubleshooting
Topic: I have a really weird problem with UDP from two Pi 1s
Replies: 0
Views: 54

I have a really weird problem with UDP from two Pi 1s

I have a Java program that sends a UDP packet to a multicast receiver on another computer. This works fine from all of my Pis. Since the Pi 1s have limited computing power I decided to rewrite the sender in C. The C sender works fine from my Pi4 but won't send packets from my two Pi1s. I listen with...
by knute
Fri Dec 03, 2021 4:02 pm
Forum: Troubleshooting
Topic: pigpiod -l option only opens ::1
Replies: 2
Views: 114

Re: pigpiod -l option only opens ::1

A network server program must create a socket(), bind() it to a local address and port, listen() on it, and then accept() connections. Each socket can only be bound to one address and port, so to listen on multiple distinct addresses would require multiple sockets. True I think pigpiod -l prefers t...
by knute
Wed Dec 01, 2021 5:40 pm
Forum: Troubleshooting
Topic: pigpiod -l option only opens ::1
Replies: 2
Views: 114

pigpiod -l option only opens ::1

pigpiod is installed with the -l option which I think only allows connections from the computer it is running on. But it only opens port 8888 on the IPv6 address ::1. If you instead use the -n option, -n localhost, it only opens the IPv4 address 0.0.0.0 and not the IPv6 address. I don't know if it r...
by knute
Wed Nov 24, 2021 11:26 pm
Forum: Networking and servers
Topic: UDP works on Windows 7 but not RPI4
Replies: 17
Views: 518

Re: UDP works on Windows 7 but not RPI4

static routers=255.255.255.0

That's not really the address of your router is it?
by knute
Fri Nov 12, 2021 3:01 pm
Forum: Troubleshooting
Topic: How to get ctsrts on uart0?
Replies: 0
Views: 42

How to get ctsrts on uart0?

There are options on the dtoverlay for uarts 2-5 for ctsrts but not for 0 or 1. Any idea how to turn on ctsrts for uart0? It would be nice to have it work on a Pi3 that doesn't have uarts 2-5.
by knute
Fri Nov 12, 2021 3:58 am
Forum: Raspberry Pi OS
Topic: STICKY: Bullseye - Comments and bug reports thread.
Replies: 488
Views: 27223

Re: Bullseye - Comments and bug reports thread.

This problem can be resolved by installing Java 8 and uninstalling Java 11. It would be nice if the default-jre-headless package knew Java 11 wasn't compatible with the Zero and other ARMv6 based models of Pi. Or you can get a v6 compatible Java 11.0.13 from Azul. It works fine on my Pi 1s and shou...
by knute
Thu Nov 11, 2021 4:16 pm
Forum: Raspberry Pi OS
Topic: STICKY: Bullseye - Comments and bug reports thread.
Replies: 488
Views: 27223

Re: Bullseye - Comments and bug reports thread.

Edit: libcamera-still is actually creating a file called - that's where all the data is going. It's tricky editing a file named -. But renaming it shows the image data is in the file. Not sure where to go here, I want it on stdout. I have a problem with libcamera-still. Setting the output to stdout ...
by knute
Fri Nov 05, 2021 2:46 am
Forum: Advanced users
Topic: mail Send Only Configuration
Replies: 4
Views: 216

Re: mail Send Only Configuration

You can send mail in many cases by connecting to the destination mail server and follow the protocol to deliver mail to a user on that system. You can do it with telnet for example: https://docs.microsoft.com/en-us/Exchange/mail-flow/test-smtp-with-telnet?view=exchserver-2019 as an example of how to...
by knute
Thu Nov 04, 2021 3:53 pm
Forum: Camera board
Topic: Camera questions?
Replies: 21
Views: 726

Re: Camera questions?

Connect a Pi camera to a Pi Zero and then setup the UVC gadget driver so it appears as a USB webcam. If you want to continue using raspistill then instead use the USB Ethernet gadget driver and run software on the Zero itself. I looked it up but I have no idea what a UVC gadget driver really does. ...
by knute
Thu Nov 04, 2021 3:44 pm
Forum: Java
Topic: New book - Java on the Raspberry Pi
Replies: 7
Views: 653

Re: New book - Java on the Raspberry Pi

I have played with diozero a while back (thought I recognized your handle). I have not tried it since you published the pigpioj. My library is incomplete but covers most of what I need it to do. I was hoping for a little feedback to prod me along but I haven't gotten any :-). http://knutejohnson.com...
by knute
Thu Nov 04, 2021 2:25 am
Forum: Camera board
Topic: Camera questions?
Replies: 21
Views: 726

Camera questions?

I have need of a USB camera that has about the same capabilities as the Pi camera but it needs to connect via USB cable because the environment is not conducive for a ribbon cable. I have no experience with USB cameras. I have written some code to collect images from the Pi camera using raspistill. ...
by knute
Thu Nov 04, 2021 2:14 am
Forum: Java
Topic: New book - Java on the Raspberry Pi
Replies: 7
Views: 653

Re: New book - Java on the Raspberry Pi

I love Java and Java on the RaspberryPi. It is a fabulous language for writing all sorts of programs. It has a huge API that makes it a complete solution for both textual and graphical programs. I haven't read either of these books. They are both pretty pricey so I don't think I will buy them for th...
by knute
Thu Nov 04, 2021 1:21 am
Forum: Java
Topic: *.jar don't execute.
Replies: 2
Views: 162

Re: *.jar don't execute.

java -jar yourJarFile.jar

What is the name of your .jar file? java -jar *.jar may not do what you want.
by knute
Thu Oct 28, 2021 7:17 pm
Forum: Advanced users
Topic: PI4 HDMI out without monitor plugged in?
Replies: 4
Views: 219

Re: PI4 HDMI out without monitor plugged in?

You may also want to use a file for the EDID instead of the default. Use "hdmi_edid_file:0=1" and "hdmi_edid_filename:0=edid.bin" (with the :1 versions if required) to load it from /boot/edid.bin. I may have to because where it is going won't really have a monitor. It's going to...
by knute
Thu Oct 28, 2021 4:58 pm
Forum: Advanced users
Topic: PI4 HDMI out without monitor plugged in?
Replies: 4
Views: 219

Re: PI4 HDMI out without monitor plugged in?

Thanks for that!
6by9 wrote:
Thu Oct 28, 2021 4:07 pm
What are you trying to achieve by enabling a port with nothing connected?
I'm working on a job that has to have two monitors and I only have one cable at the moment. Didn't want to stop working on the job until the cable showed.
by knute
Thu Oct 28, 2021 3:03 pm
Forum: Advanced users
Topic: PI4 HDMI out without monitor plugged in?
Replies: 4
Views: 219

PI4 HDMI out without monitor plugged in?

On a Pi4 how do you turn on both HDMI video outputs without having a monitor hooked to them?
by knute
Sat Oct 23, 2021 6:52 pm
Forum: Troubleshooting
Topic: vsftpd troubleshooting
Replies: 10
Views: 302

Re: vsftpd troubleshooting

I think there is a fairly common confusion that sftp and ftp have some relationship to each other. The do only in that they use similar syntax. ftp requires and ftp server and sftp uses (most of the time) a sub program of ssh. That is why your sftp still works after you removed vsftpd. I too used to...
by knute
Thu Oct 21, 2021 7:03 pm
Forum: For sale
Topic: Old Java Books [GONE]
Replies: 26
Views: 1745

Re: Old Java Books - Free

Thanks for posting. Though straying a bit off topic from the idea of free Java books, it looks to me like you have presented a C++ program rather than C. Also, does this program ever terminate? The while true loops appear infinite to me, but perhaps they aren't. For the sake of people who might wan...
by knute
Thu Oct 21, 2021 2:59 am
Forum: For sale
Topic: Old Java Books [GONE]
Replies: 26
Views: 1745

Re: Old Java Books - Free

very performant often faster than C, Please could you post some example Java code that is faster than C for an identical algorithm ? A smallish self contained program that's easy to benchmark would be Ideal. I know Java is fast, much faster than Python, but I have never known it to be anywhere near...
by knute
Wed Oct 20, 2021 9:57 pm
Forum: For sale
Topic: Old Java Books [GONE]
Replies: 26
Views: 1745

Re: Old Java Books - Free

I don't think I made it passed day 5 or so before deciding that this is a language that has nothing new to offer as far as language design is concerned, obviously never going to be suitable for performance critical or resource limited applications and hence had no possible reason to exist apart fro...
by knute
Sun Oct 17, 2021 7:02 pm
Forum: Networking and servers
Topic: UFW Not Working
Replies: 5
Views: 298

Re: UFW Not Working

sudo ufw allow 22
sudo ufw allow ssh

These are redundant. Pick one or the other.
by knute
Sat Oct 16, 2021 12:53 am
Forum: Java
Topic: Java sound audio only goes out the analog port?
Replies: 2
Views: 324

Re: Java sound audio only goes out the analog port?

See this topic: https://forums.raspberrypi.com/viewtopic.php?f=28&hilit=java%20sound&p=1626794&t=30316&sid=fb1c888591505082eaeb1e4a2f2df595#p1626794 May be this helps, did for me. I have a Pi400 and OpenJDK11. Have sound on USB via a USB soundcard. Thanks Joop99. I thought I had tri...
by knute
Thu Oct 14, 2021 2:31 am
Forum: Java
Topic: Java sound audio only goes out the analog port?
Replies: 2
Views: 324

Java sound audio only goes out the analog port?

I discovered that programs that used java sound were not making any on my Pi4. After trying numerous things that didn't work, I discovered that the sound was coming out the analog port even though all other sound goes out the HDMI port. It is configured to use the HDMI port. I don't know when this s...
by knute
Thu Oct 14, 2021 1:11 am
Forum: General discussion
Topic: Advice on best GUI framework for home apps
Replies: 4
Views: 342

Re: Advice on best GUI framework for home apps

Love those Knute, thanks for posting. Ham shack eh… GW3JVB here :D :D Can I ask, re the temperature app, how do you get the temperature sensor readings from other locations to a common Pi? I currently have several PiZeros sending temp readings from BMP280 sensors up to adafruit.io, but am wondering...

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