I am using a buildroot image (3.12 kernel) running on my raspberry Pi with a USB LED light connected to it and I want to control on/off through the CLI.
I went through this. However, there is no control or level file in the power folder.
Is there any kernel configuration that I have to enable to get this ?
Found the answer to this. I have to enable PM_SUSPEND in the kernel configuration to get the class files. But then, as mentioned in the comments, RaspberryPi has the power lines directly connected to the power rails
Related
Is it possible to work at Raspberry Pi Pico using Windows 10? My question specified is: do I have to install any Linux distro, for example Raspbian, to be able to work at it? Do I also need to use SD card to work with it?
Just want to receive feedback, cause I'm confused and also kinda new to embedded systems
I may share my experience so far, I'm not an expert and this list does not claim to be complete at all.
The pi pico can be programmed by using
Picomite Basic (found here: https://geoffg.net/picomite.html) which doesnt need anything installed on the PC except a terminal program (I am using Tera Term)
MicroPython (never used it myself, afaik Thonny - found here: https://thonny.org/ is the preferred IDE )
C/C++/ASM This is what I am using, the SDK is available for Windows, Linux and Raspbian (MacOS maybe too?), an excellent guide on how to install it and how to use it is found here: https://datasheets.raspberrypi.com/pico/getting-started-with-pico.pdf
Arduino The Pico can even be used as an arduino device too, a good point to start is here: https://github.com/earlephilhower/arduino-pico
Keep in mind, that the interpreted languages (basic and python) are easier to handle (no big SDK or framework need to be installed on the PC, copying code to the pico is a relative easy step) but at a cost of speed. If you need a lot of cpu power, compiled languages are by far the better choice
To answer your questions, yes, no, and no. You should be able to get going on Windows 10 with just the raspberry pi pico and a micro USB to USB cable.
I got started with mine this weekend - seeing the on-board LED blink finally made me so happy.
The official getting started guide pointed me at this script for getting started on Windows.
It set up docs, examples, visual studio code, and more for me. Between its README and chapter 9 of the getting started guide ("Building on MS Windows"), I was able to get my little light blinking :)
Good luck to you on your embedded journey!
As an alternative, an in addition to #Tommylee2k's helpful insights, you can develop and run Python software for a Pico with absolutely no software needing to be installed on a Windows PC.
At its most basic level, you press the BOOTSEL switch and insert the Pico's USB cable into your PC, and the few MB of space on the Pico appear in your Windows File Explorer as a USB disk drive.
You then write your microPython software using any text editor you prefer. All these general purpose modules are available. And all these Pico-specific modules are available.
You then copy (drag and drop) your Python script to the Pico disk drive and save it as main.py.
The Pico will then run that script on every subsequent power-up. Of course you can re-attach the Pico to your PC and edit the file at a later date.
That is adequate and simple enough. If you want a REPL and friendly editor and console logging and other developer-friendly features, you can install Thonny for free and code more effectively but it is not actually absolutely necessary. It's a bit like driving a car without ABS, without an automatic gearbox and without aircon - it can get you from A to B without problems but there are easier and more comfortable methods.
I am newbie to yocto world, learning and trying to develop small projects.
I want to interface graphical lcd with raspberry pi 3, what interface should I use?
I have build a yocto image for raspberry pi and running on it.
What changes do I need to make in yocto image to display something on glcd.
To begin with, you will have to read the specification of the lcd you have chosen. This way you will be able to see if it is LVDS, RGB, etc as well as calculate the timings according to your requirements so that the display works as expected. Here is some information.
Once you have that background you need to know about how Linux displays images, I leave you another resource here. Basically you have to add the previously collected information to the kernel driver that manages the KMS interface (Kernel Mode Setting, part of the Direct Rendering Manager (DRM) interface.
It will also be important that you supply the kernel with the desired display resolution, among other things, in the kernel argument line.
Since I cannot get the manifold 2 in my region, I created a cable according to https://forum.dji.com/forum.php?mod=viewthread&tid=219723.
The cable is connected via FTDI converter directly to the drone's OSDK port.
when connected to a serial terminal application I get data from the drone
Terminal
When I try to debug the flightcontrol-sample in Linux, I get the following:
LinuxOutput
Data is also received in Linux using 'screen' command.
testing the cable for 'loopback' works fine.
I have changed the port baud rate to several options (230400 & 921600) to no avail.
the ACM cable is connected through an additional USB port to the drone's port directly.
Am I missing some HW components in my setup?
I have entered all the relevant Linux commands to get the required permissions as advised in
https://developer.dji.com/onboard-sdk/documentation/quickstart/development-environment.html
&
https://developer.dji.com/onboard-sdk/documentation/quickstart/run-the-sample.html
Am I missing something in that department?
The final goal is to use STM32 as FC, but testing is easier using the Linux environment.
Any additional things I can test?
Are there other working setup designs I can try?
Thanks for your help.
i got M300 osdk connection up at Apr 2020.
So far not many issues. There are many tricks and rules that you need to follows e.g osdk adapter board usb type C seam side face inside. make sure osdk adapter board is powered up by checking the output supply voltage. 3.3V FTDI. and make sure it is pull up properly by checking voltage as well
After you check through the hardware.
the software has many tricks as well. for M300 only osdk/osdkros 4.0 and above can drive. The new userconfig.txt format changed and you have to change accordingly. and you can go through my checklist which I posted on DJI forum https://forum.dji.com/forum.php?mod=viewthread&tid=216529
If you really still have a problem. do provide photos on your connection, the terminal output for the error message.
As Dr. Yuan suggested, have a look at the UserConfig.txt file. Depending on which OSDK version you are using, it has a different format.
In my case, using osdk 3.9 configuring it this way solved my issues:
app_id : xxx (number)
app_key : xxx (number)
device : /dev/ttyUSB0
baudrate : 230400
Also check your FTDI cable, it once burned out for me and it was the reason for this error too. You should try a new one just in case.
I use the OSDK with a raspberry pi, in case you are using this kind of linux environment, I suggest you check the configuration files (cmdline.txt and config.txt) doing sudo nano /boot/cmdline.txt and same for config.txt.
my configuration for cmdline.txt is:
dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait
And for config.txt just add this at the end:
enable_uart=1
init_uart_clock=64000000
start_x=1
I hope these can help and that I am not too late.
I'm working on a Cyclone V SOC FPGA from Altera with a double Cortex-A9 processor. The embedded system (linux 4.15.7) is created with Buildroot-2018.02. U-boot is used to load the system i-e FPGA.rbf file, device tree blob and zImage and everything works fine.
I want now to integrate the RBF file to my linux and program the FPGA from Linux. I found several methods and the one I understand is the most common is to use CONFIGFS with a device-tree overlay.
So I changed my device tree to integrate the overlay, the u-boot boot script to disable FPGA load and also the following options in the linux ".config" file with make linux-xconfig :
+CONFIG_OF_OVERLAY=y
+CONFIG_ALTERA_STAPL=y
+CONFIG_CONFIGFS_FS=y
+CONFIG_SAMPLES=y
+CONFIG_SAMPLE_CONFIGFS=m
These options are the state were I am now after several try.
After a make and a reboot, once the kernel is loaded, I enter the following command in the console :
mkdir /config
mount -t configfs none /config
At this state, I'm expecting to see some device tree files in the /config folder but there wasn't any, only one rdma_cm folder :
# ls /config
rdma_cm
I continued my reading on this topic and found that I must enable the CONFIG_OF_CONFIGFS option in my linux kernel.
PROBLEM: This option is not available in my linux kernel. Also, file drivers/of/configfs.c is no here too. I've searched in vain to find how to enable device tree overlay for my kernel version.
How can I configure my kernel to make device-tree available in configfs ?
I had the same problem as you. So I had to make a device driver by myself.
This device driver is tentative and I expect Linux mainline to officially support Device Tree Overlay ConfigFS.
The device driver I made is available at the following URL.
https://github.com/ikwzm/dtbocfg
If you are using Debian, you can build the Debian Package of the device driver with the following URL.
https://github.com/ikwzm/dtbocfg-kmod-dpkg
If you want to try Device Tree Overlay using this device driver, please refer to the following URL.
https://github.com/ikwzm/FPGA-SoC-Linux
https://github.com/ikwzm/FPGA-SoC-Linux-Example-1-DE10-Nano
I have a laptop installed windows 7 x64 and a virtual machine with Ubuntu 12.04. I installed Bootchart on my virtual machine. I can view bootchart diagram of my virtual machine after log it on.
But I wonder... Is there any way to view bootchart diagram of an embedded device such as my android smartphone if i connect it to my laptop?
Can you help me to solve this? Thank you very much.
If you are a developer with the Android source code, you can use the following method and the bottom link to enable the bootchart on you smartphone.
brief instruction is like:
install the bootchart tool on your host machine
build 'init' with bootchart support
install 'init' into your system image
trigger bootchart functionality on system boot
retrieve the collected data from the system
generate the graphic from the data
view the resulting graphic
interpret the results
and more details please refer to :
http://elinux.org/Using_Bootchart_on_Android
dmesg command will be the one of the most helpful tool in providing log messages right from beginning of booting as far as any operating system based on linux. It prints the message buffer of kernel and it should also enable you to decode the boot sequence. You can also redirect the kernel messages using the 'console' command via the interface(UART / USB) that is available on the device.
Another interesting tool that could work in tandem with dmesg is netconsole if the device does not provision for other interface based logging or issues in disk logging. It sends all kernel log messages without any dependency on userspace, to another computer over the network (UDP) . However note that netconsole initializes only after NIC card initialization and hence capture of early kernel logs before this point will not be there but captures the rest of the boot process.