I have paired the barcode reader with a data entry device through bluetooth SPP mode. While reading code 128 barcodes, some of the leading characters are missing. For example, if I scan a barcode for 'FXRGYKD', I could only see 'GYKD' in the device. The barcode readers that I have tried with are 'Socket Mobile CHS 7DI' and 'Symbol CS3070'.
Thanks in advance!
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Some keyboard related software like Karabiner for macOS and the QMK firmware uses the names left_gui, right_gui, KC_RGUI, KC_LGUI for the Command key. And I found that also corresponds to the Windows key if using Windows OS.
Where does the name GUI come from historically?
The name GUI comes from the USB HID (Human Interface Device) specification.
The scancodes/keycodes for the keys labeled Windows/Meta/Command are named GUI in the USB HID specification. For example the section 8.3 Report Format for Array Items of the USB Device Class Definition for Human Interface Devices (HID) 1.1 spec says :
For example, key such as CTRL, SHIFT, ALT, and GUI keys make up the 8 bit modifier bytes in a standard keyboard report.
I try to use USB keyboard with PIC32MZ1024ECG64 in USB host mode, but the PIC can recognize the keyboard only if the keyboard already connected before I release the PIC from reset.
If I disconnect the keyboard and I attach it back then the PIC cannot recognize it, but if I just disconnect the D- and D+ lines only and I connect those lines back then the PIC can recognize the keyboard again.
When I disconnect the keyboard (not only D- and D+) and take look the USBOTG register, the PIC switched itself to the USB-B mode and stay in this mode.
I using MPLAB Harmony with 1.06 library.
The VBUS3V3 pin connected to 3,3V supply, the VBUS pin connected to 5V supply and the USBID pin connected to the ground.
Anybody has any idea why the PIC switching itself to the USB-B mode when I disconnect the USB connector of the keyboard?
Any suggestion will be appreciated.
Br,
Viktor Venczel
I want to use uinput to emulate pressing the menu key just next to the right Alt key. I tried KEY_MENU and KEY_CONTEXT_MENU, but neither of them worked. The key in Win32 API is VK_APPS.
KEY_COMPOSE is the correct Kernel keycode.
Some elaboration from Chromium’s keyboard event notes:
'Menu' and 'Props' naming differs between evdev and USB / UI Events. USB 0x010085 [System Main Menu] and USB 0x0C0040 [Menu Mode] both map to evdev 0x8B KEY_MENU (which has no corresponding UI Events |code|). USB 0x070076 [Keyboard Menu] does not map to KEY_MENU; it maps to evdev 0x82 KEY_PROPS, which is not the same as USB and UI Events "Props". USB 0x0700A3 [Props], which does correspond to UI Events "Props", is not mapped by the kernel. (And all of these are distinct from UI Events' "ContextMenu", which corresponds to USB 0x070065 [Keyboard Application] via evdev 0x7F KEY_COMPOSE, following Windows convention.)
I have a barcode scanner works as HID device. Everytime a barcode scans it goes directly to windows keyboard, for example if I open notepad I can see the barcode typed there.
As far as I know programmatically is it possible to to read HID data from your HID devices.
But what happens if the user is already on a form with a text edit control? The scanned code will go inside the text box.
Can you block incoming text and make a background-only processing?
Can you explain the theory please?
See if your barcode scanner can emulate a serial port and just read the data directly from the the serial port into your app.
That is cleaner and less expensive then a global keyboard hook. When I was looking into this awhile ago I found that most USB barcode scanners can emulate a serial port, it's a cinch to read serial port data in most programming languages. I happened to be doing mine in Java, I posted an example in answer to this question actually.
You can set up your scanner to use USB-HID(POS) setting. Your datasheet of barcode settings for the scanner device should have it. I use this project to test my scanners. http://www.codeproject.com/Articles/18099/A-USB-HID-Component-for-C
Sure, just capture keypresses before they are handled by the control and suppress normal handling of the events. In VB.NET you might override the OnKeyPress method in your form and set KeyPreview to true, for example.
When my barcode scanner scans a code, it adds ] to the beggining and [ to the end. How can I change this?
Unfortunately, it's a barcode scanner setup parameter and varies by the particular barcode reader. You will need the documentation / SDK for your barcode scanner. Many barcode scanners can setup the leading/trailing character just by scanning a setup barcode.