Questions tagged [keyboard]
A Keyboard is an input device typically made of a large array of switches. The interface could be the raw matrix, or an industry standard protocol like PS/2 or USB.
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Tricking CPU's with specially crafted RF signals
Is it possible that I can modulate and craft a RF signal that, once demodulated by a WiFi card and turned back into electrical signals or binary data, can trick the CPU into thinking it's a command ...
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Connected my keyboard to Apple 67W USB-C Power Adapter: Voltage Concerns [closed]
I recently had an experience with my keyboard (HHKB Professional Hybrid Type S) that I wanted to get some additional insights on.
Specifically, I accidentally connected my keyboard to a 67W Apple USB-...
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Wireless Keyboard RGB backlight design
I am designing a split wireless keyboard with a 3.7V 2000mAh LiPo battery and using the BQ24075 for power management. I'm contemplating the use 32 of the SK6803 Mini-E for backlighting. Is this ...
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How can I replace the keyboard lights with 12 volt lights?
I had an idea in mind: connecting the three keyboard lights to three external lights that operate on a 12-volt current by using an NPN transistor circuit. However, when I tried to implement the idea, ...
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What is it needed to repair the pressure pads of an electric piano keyboard? [closed]
I don’t know if this is the right place to ask, but this is important to me, so i hope you understand. I have an electric piano keyboard (Korg Kross I). It is supposed to detect automatically the ...
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Multiplexed keyboard based on MOSFET for AVR gives sometimes wrong reading
I made simple example for multiplexed keyboard 2x2 on AVR. Like schematic below:
And Source code:
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Schematic design review of a custom macropad with an ATmega32U4
This is the first time I've made a "more complex" PCB. Before I buy all the parts it would be nice if someone could check my design.
ATmega32U4: Datasheet
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Scanning a keyboard matrix
I recently watched a video on YouTube by Branch Education.
In this video, they describe two methods for scanning the matrix:
Sequentially apply a voltage across each column so that at any instant ...
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The receiver sends correct but too much information to the keyboard with STM32 nRF24
I have a problem with keyboard hid. I did remote control with STM32 transceiver nRF24. My problems that receiver true receiving incoming data but too much text. Problems that:
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What would be the best (simplest?) practice for redirecting power and data lines based on the presence of a host usb connection or it's absence?
Basically I'm trying to use a Handheld Scientific BT-500 bluetooth keyboard adapter to make an existing keyboard wireless. The way the module works is if power is supplied (but no data) it activates ...
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Identifying Cherry MX-5000 Keyboard controller chip ZC86963P
The Cherry MX 5000 ErgoPlus keyboard (model G80-5000 HAAUS) has been out of production since the 1990s. I'm trying to identify its controller chip. If I can locate a data sheet, I hope to dump the ...
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Can I connect ESP32 GPIO to USB D+ and D- through a CH340 converter?
I want to see what a wired keyboard (and later a mouse) outputs to an ESP32, so I am thinking of connecting a wired keyboard's USB to a CH340 (USB to UART) converter and then connect it to GPIOs of an ...
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How does the Dumang DK6 keyboard work? [closed]
The Dumang DK6 keyboard is a modular mechanical keyboard, where each key is mounted into an independent saddle with its own microcontroller, and each saddle can be independently positioned anywhere on ...
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How do I connect to the strange black contacts on a PC keyboard's PCB?
I want to build a little box with switches, so that I can flip a switch and it will hold down a keyboard key on my PC. My idea is to take the little PCB from an existing keyboard (a Microsoft Wired ...
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Identifying a keyboard component
Recently I found an old ACER 6312-TA keyboard that I want to repair. Everything seems to work fine except for this component that I can't identify:
I bet the reason this keyboard is not working has ...
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BLE HID Keyboard Device for iOS
I'm using a Dialog SmartBond DA14531 as a BLE HID Keyboard device. It works on Windows but not on iOS. Although it pairs successfully, the HID key events do nothing. Does anyone have any experience ...
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What signals does the flat cable send in laptops?
Can the flat cable through which the internal keyboard in the laptop is connected transmit PS/2 or USB signals? Or does it send some other signals like serial or parallel, which are then converted on ...
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Best approach to driving custom RGB mechanical keyboard LEDs
I am in the middle of designing a custom mechanical keyboard and have just finished the PCB schematic, but before I spend a few hours placing and routing components, I thought I might ask y'all a few ...
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Keyboard inside glove [closed]
I have an idea on keyboard inside a glove. You would wear a glove which would have little switches inside every finger. When tapping with the finger it would send the index of the finger to the ...
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PCB design review (ATmega32U4 keyboard PCB)
I've been working on an ATmega32U4-based PCB for a custom keyboard for a while now. I made a few prototypes with similar designs, but they all seemed to have issues with the microcontrollers dying ...
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Joining two rigid PCBs in a non-flat configuration [closed]
I would like to design a very minimal split keyboard like the GergoPlex or Ferris Sweep, but my wrists get sore easily with extended pronation and ulnar deviation.
As such, the design I have in mind ...
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Keyboard diode design
I have a question about keyboard diode placement. (Pardon my ignorance if this is simple question I have no electrical engineering background.)
The diagram below shows how a keyboard schematic is laid ...
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Mysterium Keyboard ATmega32a malfunctioning. "USB device not recognized."
I tried sourcing all the parts for this keyboard.
I soldered everything up and when I plug in the keyboard I immediately get an error message "USB device not recognized":
My first though ...
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Will a Casio keyboard work with a lower current adapter? [duplicate]
My electronic keyboard uses a 12V 2 ampere adapter. Will it work with a 1 ampere adapter?
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STM32 USB HID Keyboard skipping key presses
I have an STM32F3DISCOVERY evaluation board which has an stm32f3 mcu on it. I am trying to use the board to emulate a USB keyboard.
I used the STM32CubeIDE to enable USB communication, configure the ...
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Keyboard Repair: Both Shift Keys Dead [closed]
I have an old notebook working perfectly fine. The only issue is that both shift keys are completely dead:
keyboard top view
keyboard bottom view
...
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Can a PS/2 keyboard be converted to USB hot swap (plug)? [closed]
I have an old keyboard made in 1998, and I want to use it, but my computer does not have a PS/2 port.
I bought an adapter to convert the PS/2 of the keyboard to USB. I know PS/2 cannot hot swap.
But ...
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Replacing a keypad on DYMO LetraTag
I'm rebuilding my label printer to become an Internet service using an ESP8266. It's a fun project, never mind the usefulness. The keypad will be removed and instead my MCU emulates keypresses.
The ...
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Could anybody help identify this connector?
Would any of you recognize the following connector ?
It's on a old Dell laptop motherboard (M3800). It's to connect the led circuit from the lit keyboard.
The flat brown cable from the lit keyboard ...
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Purpose of PNP transistors connected base to base in 1V/Octave synthesizer keyboard circuit
The circuit below (found here) is designed to be used in a 1V/octave keyboard used to control a synthesizer. When the potentiometer is adjusted properly, pressing the buttons produces output voltages ...
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What can this pin on my keyboard connector be?
I'm trying to place a USB-C connector on my keyboard so I can use a removable cable with it. It's a Ozone Strike Pro with audio and USB pass through. I managed to map 10 of the pins with a multimeter ...
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STM32 matrix keyboard scanning gets random keypresses
I am trying to implement a keyboard with STM32 controller (since I managed to burn all my ATMegas and STM32 was all I have).
It uses two matrices of keys (it was supposed to be a split keyboard, but ...
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Teensy++ 2.0 doesn't jump into bootloader using software
I have a Teensy++ 2.0 with 90USB1286 CPU running QMK. I'm trying to make it jump into the bootloader using the QMK software. I tried two approaches:
Mapping a RESET...
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What is the difference between making a resistor based keypad and not using a resistor on arduino? [closed]
I've seen videos on youtube about how to emulate a keypad on arduino. Some of them includes a resistor while others do not. What are the difference between them and are there advantages in doing one ...
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How can this 74 series Inverter circuit be analyzed?
I'm trying to analyze the keymech scanning / sampling circuit in the WASP synthesizer
So far I understand that the keymech is sampled one key at a time by the 74 series logic driven by the dual ...
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How to communicate when a packet starts and ends (send two bytes in one packet)
I am aware that there are some libraries around this topic and that it would be easy to make this type of keyboard if I'll use different kind of arduino. I am doing it for learning purposes and couldn'...
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Unusual USB keyboard wiring - repair needed
New to anything electrical, and I'm trying to make an urgent fix for my wife's keyboard. She has a disability, so needs a specific keyboard to work, and the USB plug on the keyboard has been damaged ...
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Keyboard column not responding
Have a keyboard with hotswap sockets that was previously working... suddenly one column no longer works. Specifically the column consisting of 6yhn does not work anymore.
Here is a link to the ...
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Decoding and connetting a keyboard PCB [closed]
I want to build a laptop from a raspberry-pi and an old "toy laptop" (and new components), the spare toy laptop I have is a Oregon Scientific Batman BL31T. I would like to use its case and ...
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Not detecting closed circuit in Goldtouch keyboard key presses
Context
While converting the Goldtouch Go!2 Mobile keyboard from Bluetooth to micro USB, I'm experiencing some difficulties in registering the keystroke signals coming out of the FPC connector.
Setup
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How to add many I/O lines to a microcontroller for my custom computer keyboard?
I think that this is a design question because I need to know what type of chip to use first, and then I'll go shopping on my own for which one to use.
I need to understand how to add at least 90 ...
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When to switch to 4 layer PCB
I'm currently designing my own 60% per-key RGB mechanical keyboard.
(60% means the keyboard only contains 60% of the keys of a regular keyboard.)
I've laid out the components, routed the switch scan ...
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How to connect membrane tracks on a keyboard? Problem on photo
How to connect membrane tracks on a keyboard?
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What do I find material to understand which electronic components are needed for a microcontroller?
I'm interested in designing a PCB for a keyboard, and I can't seem to find materials on learning what components are needed for the board (resistors, capacitors, diodes etc). I understand basic ...
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Circuit paths on a plastic sheet of a Model M keyoard are dark brown and don't forward electric signals any more. Are they corroded?
I'm trying to repair a 2015-issue Model M keyoard whose couple of keys don't emit any scancodes any more. After I have excluded some obvious culprits (stuck keys or springs, debris etc.) and ...
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Unable to correctly send keypresses using the LUFA library
I'm making a board with an atmega32u4 on it for the controller for a keyboard, and am having issues with telling the host computer that a key is pressed. I've modified the Keyboard demo supplied with ...
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PS/2 keyboard with RS232 (DB9) workstation port
I'm currently awaiting for dispatch/delivery of a 1995 PS/2 Model M keyboard w/attached flat cable but a missing PS/2 plug
It seems those flat cables were not very sturdy.
(Yes, I checked the model ...
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Is there a fake way to drive a matrix keyboard (to use a typewriter as line-printer)
I recently found a Brother AX-425 typewriter, I want to be able to control it via a computer.
Its internal electronic seems pretty simple, it's a 8*8 matrix ...
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How to detect pinout of trackpoint (probably ps/2) module?
I have following trackpoint module of recent thinkpad x390.
There are some info about older modules, most useful(combined) one is: https://deskthority.net/wiki/TrackPoint_Hardware
However, i found no ...
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What ASIC/MCU is in my keyboard?
I disassembled my unbranded USB keyboard to find out what ASIC/encoder/MCU is inside. The chip is (as expected) covered, like the following example:
How to find out which chip is underneath?
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