Free combination inline keyboard, modular design, the first choice for beginners [Pro Micro]

This project is the simplest programmable inline keyboard with RGB, suitable for beginners to make the sister version of https://oshwhub.com/iqirtryi/pbk40-rgb-keyboard-c. It is composed of three identical PCBs spliced ​​into a 48-key inline keyboard, so it has one more column on the left and right than this project, with independent copy, cut, and paste shortcut keys.
 
Because the Pro Micro module is used as the main control, the circuit is very simple and suitable for beginners to make.
 
The same PCB is freely combined into 16, 32, and 48-key inline keyboards, and the size meets the requirements of free board making. RGB lights are configured to display the layer status. There are
 
two design options for positioning board and base board: you can make a whole board, which is a trouble-free choice; you can also divide it into two pieces, which is a cost-saving choice.
 
It adopts a stacking structure, which is simple and easy to make. Type C interface, convenient and easy to use.
 
Open source QMK program, full key programmable. There is a small hole at the bottom for easy firmware burning.
 
All 1U keys are used, the keycaps are simple and cheap, there is no satellite axis, and the cost is low.
 
Carefully designed unique layout, comfortable and efficient:
 
the carefully designed small layout setting, all keys are within the comfortable operation range of ten fingers, and the little finger does not need to press the keys outward;
the most frequently used enter key and backspace key are under the little finger of the right hand, and can be operated without moving; the keys for switching between layers 1 and 2 and the shift and space keys are under the two thumbs, and the thumbs are no longer just used to press the space bar, and the utilization rate of ten fingers is effectively improved; the left thumb presses the Fn1 key, and under the left hand is a complete numeric keypad and operation symbols, which is very suitable for left-hand numbers and right-hand mouse operation; the right thumb presses the Fn2 key, and under the right hand are the up, down, left, right, Home, End and other direction keys. The gesture is similar to holding a mouse, which is natural and comfortable, and is especially convenient for moving the cursor when typing; all punctuation marks only require the thumb to press the Fn1 key or Fn2 key, and the fingers of the other hand press the corresponding keys, and all key positions are within the finger comfort zone; the left thumb presses the Fn3 key, and it is simple and easy to press the F key with one hand, and the right hand Fn3 key is a virtual mouse...
 
 
 
 
 
 
Of course, compared with the large layout keyboard, the small keyboard must be learned and proficient by yourself, and after forming muscle memory, it is convenient and efficient. The key settings are also becoming more and more perfect with my continuous use.
The attached files include the verified firmware .hex file and the QMK source code.
 
Production Notes:
The welding of Type C and 32a chips is a bit difficult for novices. It is recommended to use a heating table and solder paste to complete it, which is much more convenient than a soldering iron. Except for the key switches and individual components, basically everything can be done with a heating table. To weld this small board, apply solder paste to all the pads of the patch components, place the components except the C port and 32a chip, heat it, wait for the solder paste of the C port and 32a chip to melt, use a sharp object to cut off the tin, and then accurately place the chip and C port, press for a few seconds, and solder all the patches at once, 100% successful, fast and good! Those who have no experience can search for relevant content on Station B to learn, and be careful not to weld for too long to avoid damaging the components. The heating table shown in the above picture is from Taobao. I DIYed a PCB heat insulation bracket, which is simple and practical. For details, please refer to: https://oshwhub.com/iqirtryi/heater-holder For
 
 
detailed production process, please refer to: https://oshwhub.com/iqirtryi/pbk40-rgb-keyboard-c
For purchase link of main components: https://docs.qq.com/doc/DYWFPbGdhZ0puV2V6
 
If you need to reduce the height of the keyboard and reduce the cost, you can choose a slightly more complex chip solution:
https://oshwhub.com/iqirtryi/pkb16x4-atmega32a 
 
The minimalist 30-key keyboard is waiting for you who pursues more simplicity. Do you have the courage to try it?
https://oshwhub.com/iqirtryi/IQP30A-atmega32a
 
For more small layout keyboards, please see: https://oshwhub.com/iqirtryi
 
A must-read for beginners! ! ! A must-read for beginners! ! ! A must read for beginners!!!
Important things should be said three times. If you want to successfully complete your first homemade keyboard, it is recommended to read the following information carefully. Thanks to all the experts for their contributions:
1. Must-read guide:
Zero-based assembly: https://www.zfrontier.com/app/flow/2wqGYOQPMpOQ
Quickly learn to make your own: https://www.bilibili.com/read/cv5275203/
QMK flashing tutorial: https://post.smzdm.com/p/aekz8pdm/  
2. Advanced reading: QMK environment construction: https://www.bilibili.com/read/cv10071032/
RGB light setting: https://www.zfrontier.com/app/flow/2dq9AoE37KpE 3. Tool website: QMK official website: https://docs.qmk.fm/#/zh-cn/ Layout editor: http://www.keyboard-layout-editor.com/ Online firmware generation: https://kbfirmware.com/ Positioning board shell: http://builder.swillkb.com/  
 
Thank you for your attention. If you find it interesting, please like + comment + collect it!