I am learning linux-kernel and driver, and just a newbie. I want to write a "driver" which can get PID/VID of any usb device, then print those numbers into kernel log.
As far as i know, USB HCI detects PID/VID from attached USB device,and pass to usbcore, even if it does not have right driver. So there must be some APIs to get it, but I dont know.
Any one can help me?
Please use 'lsusb' to get those details
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I'm trying to read/write data to a USB flash drive.
I have read in the reference manual that STM32F103xx has a USB peripheral but can only act as a device in the communication. From what I understood, I need it to act as a host. Is there anyway to do this operation without USB to UART converters as I'm trying to be more efficient(in a financial sense).
I seem to find no clue on the internet regarding this particular MCU.
If this can be done only with a UART converter, please show me where to look.
Thank you!
As multiple people pointed out, STM32F103C8 can't be a host in the USB communication protocol, therefore the transfer of data cannot be done.
I made a mistake when I thought the USB to UART converter will solve the problem. The converter doesn't have a mass storage protocol implemented on it, therefore it cannot read the data.
See the comments for answers.
I am trying to learn Linux by following instructions in "Mastering Embedded Linux Programming" by Chris Simmonds. By following the book and with some help from Stack_Overflow_1, i was able to build the MLO and u-boot.img.
However, when i connect USB cable to my PC and execute the ls /dev/tty* command, i cannot find any device with /dev/ttyUSB. All i can see are devices with /dev/tty0-63, /dev/ttyS0-31 and one /dev/ttyprintk.
Also, when i press down the S2 button and connect the USB cable, i can only see the power led glowing and nothing else.
I have properly built the u-boot (three attempts to get it right).
Also, as per the instructions in the book, i am only testing the u-boot stuff and yet to reach the kernal part.
If i remove the sd card and connect the USB, im an able to talk to my BBB over ssh (192.168.7.2).
How to i get the u-boot to work? Thank you!
If you don't have one yet, I'd recommend to get a USB-to-serial device (3.3V Vref). You connect it to the debug UART (J1) which is located next to the P9 side. Nowadays those are very cheap and can cost below 1$. Ones that feature a genuine FTDI part will be 5-10$ at least.
The serial port you are referencing is only available once the device has passed through U-Boot, booted the kernel and finally userspace has set up the communications.
Especially when working with U-Boot and the Kernel, low level UART access is crucial.
As a further note, could it be that the Book refers to the (white) original Beaglebone? That has a FTDI USB-to-UART chip on board and will allow you even U-Boot access. You can do the same things if you have the above mentioned USB device.
https://groups.google.com/g/beagleboard/c/eNDjK05spY8/m/GPvhcP52BAAJ shows that one needs to hold the space key to enter u-boot.
Also, the info. here might be more up to date compared to the book.
https://www.digikey.com/eewiki/display/linuxonarm/BeagleBone+Black
There is no way to copy and paste everything from the eewiki. I just left you the link. Enjoy!
I have got Arduino MEGA 2560. What I would like to do is to send a signal to Arduino via serial port to light specified LED up. However, I cannot find any documentation about this. What steps should I follow?
I think first, I need to compile the driver of Arduino and add it to Linux kernel. Second, I have to find some header files to use them in module. Then, I have to find functions to start serial communication and to light LEDs up. However, these are just my thoughts.
Any advice will be appreciated.
The arduino-mega (the one with ATmega2560) documentation is here:
https://www.arduino.cc/en/Main/ArduinoBoardMega2560#documentation
The serial communication via UART:
https://www.arduino.cc/en/Reference/SoftwareSerial
Since there are other ways for serial communication with the ATmega please read the documentation [above] and compare that to your exercise sheet.
I think such a kernel module is already available - and used by the arduino-ide.
I bought a usb otoscope from the internet and I want to create an application that uses it. When I plug it into the computer, it reads the device as a USB Camera, and I can use the very barebones software supplied to communicate with it. I'm very new to the idea of communicating with usb all together. I've tried to look at some sites like this: http://www.jespersaur.com/drupal/book/export/html/21, that tell me how to reverse engineer a device. I don't know if I'm going down the right path with this...
I've downloaded USB Snoopy and I can't seem to get it to sniff the packets correctly. I also have Crunchbang linux installed on a different computer but I don't know how to sniff it on that either (especially because the drivers are native to windows). All I want is some sort of API/Interfacing functions for me to call and use. How do I go about doing such a thing? I'm able to locate the device on the device manager in windows, and it tells me hardware ID's and such. I can supply any information if necessary. Thank you.
EDIT - Small description I found of the otoscope: http://microscopesimgv.blogspot.com/2012/08/oasis-ehev2-usbplus-20mp-handheld-usb.html
would this tool help you any?libusbx is a cross-platform user mode library that provides generic access to USB devices
CHEERS!
I am writing a mini-filter code for USB (Flash Drives) for blocking i.e (Access Denied).So, could someone help me out, how to detect or block USB or what methods to use in passThrough WDK sample code for USB detection and USB blocking?
I am trying to use *IOCTL_STORAGE_QUERY_PROPERTY in PFLT_INSTANCE_SETUP_CALLBACK*. Am i on right path?? if yes then how to use IOCTL_STORAGE_QUERY_PROPERTY in PFLT_INSTANCE_SETUP_CALLBACK???
After 3 months of work I have finally achieved blocking.
Though I can't give direct code here.
But following link might help.
PassThrough Development
GitHub Link
One way could be to get the device object using FltGetDiskDeviceObject and then check for FILE_REMOVABLE_MEDIA flag in device_object->Characteristics. Once you get to know about the device type, then you can block or allow the required operations (that you need to register with FLT_OPERATION_REGISTRATION).