DESKHOP两台电脑键盘鼠标共享器-基于RP2040芯片

这是一个用于两台电脑共享一套键盘鼠标的小东西，移动鼠标，键鼠就可以在两台电脑间自由切换，相当丝滑！

原作Git链接：https://github.com/hrvach/deskhop

我只重新设计了PCB，开源软件还用原作者的！

已测试有线鼠标，2.4G无线鼠标支持都没问题，蓝牙鼠标不支持！键盘测试了我自制的机械键盘和普通有线键盘，自制键盘有线模式没问题，蓝牙模式则不支持，有线键盘我有一款Dell的键盘也不行，插入一直输入空格键不知道什么原因！

操作系统测试了Win10 Win7 WinXP和纯国产电脑龙芯CPU操作系统为中标麒麟，都没有问题，测试见附件两个视频！

使用方法：

1.刷入固件方法：开关拨到A，插入电脑，电脑会出现个U盘，将board_A.uf2文件复制到新出现的RP U盘中！

                            开关拨到B，插入电脑，电脑会出现个U盘，将board_B.uf2文件复制到新出现的RP U盘中！

2.使用：放置在左边的电脑使用type-c线插入B接口，右边的电脑则插入A接口，开关随便拨到A或B都可以，拨到哪里整个器件和键盘鼠标就由哪台电脑供电！鼠标从B电脑的右边再往右移就会出现在A电脑的屏幕中，此时键盘鼠标就对A电脑起作用；反之，从A电脑左边往左移就会出现在B电脑屏幕，此时键鼠作用于A电脑！

原作PCB：用的是两块Pico开发板设计的底板！

我的PCB：基于两颗RP2040芯片设计，小巧优雅多了！

原作的介绍：（复制自Github）

To get the mouse cursor to magically jump across, the mouse hid report descriptor was changed to use absolute coordinates and then the mouse reports (that still come in relative movements) accumulate internally, keeping the accurate tally on the position.

When you try to leave the monitor area in the direction of the other monitor, it keeps the Y coordinate and swaps the maximum X for a minimum X, then flips the outputs. This ensures that the cursor seamlessly appears at the same height on the other monitor, enhancing the perception of a smooth transition.

Dragging the mouse from Mac to Linux automatically switches outputs.

The actual switch happens at the very moment when one arrow stops moving and the other one starts.

Acting as a USB Host and querying your keyboard periodically, it looks for a preconfigured hotkey in the hid report (usually Caps Lock for me). When found, it will forward all subsequent characters to the other output.

To have a visual indication which output you are using at any given moment, you can repurpose keyboard LEDs and have them provide the necessary feedback.

It also remembers the LED state for each computer, so you can pick up exactly how you left it.

Option 1 - Open the case, hold the button while connecting each Pico and copy the right uf2 to it.

Option 2 - Switch a board to BOOTSEL mode by using a special key combination (listed below).

This will make the corresponding Pico board enter the bootloader upgrade mode and act as USB flash drive. Now you can drag-and-drop the .uf2 file to it (you might need to plug in your mouse directly).

Ever tried to move that YT video slider to a specific position but your mouse moves too jumpy and suddenly you are moving your hand super-carefully like you're 5 and playing "Operation" all over again?

Press right CTRL + right ALT to toggle a slow-mouse mode. The mouse pointer will slow down considerably, enabling you to get the finer precision work done and still have your mouse moving normally by quickly pressing the same keys again.

If you want to lock yourself to one screen, use RIGHT CTRL + L. This will make sure you won't accidentally leave your current screen. To turn off, press the same key combo again.

Supposedly built in to prevent computer from entering standby, but truth be told - it is just fun to watch. Off by default, will make your mouse pointer bounce around the screen like a Pong ball. When enabled, it activates after a period of inactivity defined in user config header and automatically switches off as soon as you send any output towards that screen.

Potential usage example - I have a buggy USB dock that won't resume video from standby, so not allowing it to sleep can be a handy workaround.

Firmware upgrade

• Right Shift + F12 + Left Shift + A - put board A in FW upgrade mode
• Right Shift + F12 + Left Shift + B - put board B in FW upgrade mode

Usage

• Right CTRL + Right ALT - Toggle slower mouse mode
• Right CTRL + L - Lock/Unlock mouse desktop switching
• Right ALT + Right Shift + L - Lock both outputs at once (set output OS before, see shortcuts below)
• Caps Lock - Switch between outputs

Config

• Right Shift + F12 + D - remove flash config
• Right Shift + F12 + Y - save screen switch offset
• Right Shift + F12 + S - turn on/off screensaver option

Number of outputs

• Right Shift + Backspace + 1 - set number of screens to 1 on current active output
• Right Shift + Backspace + 2 - set number of screens to 2 on current active output

Set operating systems

• Right Shift + Backspace + 7 - set os to Linux on current active output
• Right Shift + Backspace + 8 - set os to Windows on current active output
• Right Shift + Backspace + 9 - set os to MacOS on current active output

This step is not required, but it can be handy if your screens are not perfectly aligned or differ in size. The objective is to have the mouse pointer come out at exactly the same height.

Just park your mouse on the LARGER screen at the height of the smaller/lower screen (illustrated) and press Right Shift + F12 + Y. Your LED (and caps lock) should flash in confirmation.

Repeat for the bottom border (if it's above the larger screen's border). This will get saved to flash and it should keep this calibration value from now on.

Windows and Mac have issues with multiple screens and absolute positioning, so workarounds are needed (still experimental). Your main screens need to be in the middle, and secondary screen(s) on the edges. Move the mouse to the screen with multiple desktops and press right shift + backspace + 2 if you have 2 desktops and right shift + backspace + 7, 8 or 9 depending on your OS (Linux, Windows, Mac).

Mouse speed can now be configured per output screen and per axis. If you have multiple displays under Linux, your X speed might be too fast, so you need to configure it in user_config.h and rebuild. In the future, this will be configurable without having to do that.

When you connect a new USB peripheral, the board will flash the led twice, and instruct the other board to do the same. This way you can test if USB and outgoing communication works for each board.

Do this test by first plugging the keyboard on one side and then on the other. If everything is OK, leds will flash quickly back and forth in both cases.

Some features are missing on purpose, despite the fact it would make the device easier to use or simpler to configure. Here is a quick breakdown of these decisions:

• There is no copy-paste or any information sharing between systems. This prevents information leakage.
• No webhid device management or any inbound connectivity from the output computers, with the only exception of standard keyboard LED on/off messages, hard limited to 1 byte of data.
• No FW upgrade triggering from the outputs. Only explicit and deliberate user action through a special keyboard shortcut may do that.
• No plugged-in keyboard/mouse custom endpoints are exposed or information forwarded towards these devices. Their potential vulnerabilities are effectively firewalled from the computer.
• No input history is allowed to be retained.
• Outputs are physically separated and galvanically isolated with a minimal isolation voltage of 2kV.
• All packets exchanged between devices are of fixed length, no code is transferred and no raw config exchange of any kind can take place.
• There is no bluetooth or wifi, networking, Internet access, usb drives etc.
• No connected computer is considered trusted under any circumstances.
• Entirety of the code is open source, without any binary blobs and thoroughly commented to explain its purpose. I encourage you to never trust anyone and always make sure you know what you are running by doing a manual audit.

This still doesn't guarantee anything, but I believe it makes a reasonable set of ground rules to keep you safe and protected.