This is a simple and easy way to program a Pro mini w/o a serial adapter.
Step 1: Things You Need.
1 Arduino Uno, Mega, Leonardo, Due, or Nano,
1 The Pro Mini you are going to program.
1 Usb cable With type A plug on one end and type B on the other.
5 jumper wires to connect the Pro Mini to the other board.
Step 2: Wiring It.
Pro Mini | Programing board
Vcc 5v (or 3.3 for a 3.3 board)
Gnd to Reset on the programing board
Step 3: Programing.
Now it is ready to be programed in IDE select Pro Mini as the board.
Once the sketch is ready (no bugs) press upload, here is the tricky part as soon as it says uploading (not compiling) you must press the reset button on the Pro Mini.
This has worked for me, if you have any questions put them in the comments and I will do my best to answer them.
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