Note: Some libraries use different pad numbering – always verify with the library’s datasheet.
The Pro Micro provides 20 I/O pins, including 12 analog inputs and 7 PWM-capable pins. Arduino Docs common wiring diagrams for connecting the Pro Micro to specific sensors in EAGLE? Micro | Arduino Documentation arduino pro micro eagle library
| Pin | Signal | Arduino Pin | ATmega32U4 | Notes | |-----|--------|-------------|------------|-------| | 1 | RAW | - | - | Unregulated input (5V variant max 12V) | | 2 | GND | - | - | Ground | | 3 | RST | RESET | Reset | Active low | | 4 | VCC | 5V/3.3V | VCC | Regulated output | | 5 | TX | 1 | PD3 | Serial transmit | | 6 | RX | 0 | PD2 | Serial receive | | 7 | GND | - | - | Ground | | 8 | SCL | 3 | PD0 | I2C clock | | 9 | SDA | 2 | PD1 | I2C data | | 10 | A3 | 3 / A3 | PF4 | Analog input 3 | | 11 | A2 | 2 / A2 | PF5 | Analog input 2 | | 12 | A1 | 1 / A1 | PF6 | Analog input 1 | | 13 | A0 | 0 / A0 | PF7 | Analog input 0 | Note: Some libraries use different pad numbering –
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gate="G$1" pin="9" pad="12"/> <connect gate="G$1" pin="10" pad="13"/> <connect gate="G$1" pin="14" pad="15"/> <connect gate="G$1" pin="15" pad="16"/> <connect gate="G$1" pin="16" pad="14"/> <connect gate="G$1" pin="A0" pad="17"/> <connect gate="G$1" pin="A1" pad="18"/> <connect gate="G$1" pin="A2" pad="19"/> <connect gate="G$1" pin="A3" pad="20"/> <connect gate="G$1" pin="GND@1" pad="3"/> <connect gate="G$1" pin="GND@2" pad="4"/> <connect gate="G$1" pin="GND@3" pad="23"/> <connect gate="G$1" pin="RAW" pad="24"/> <connect gate="G$1" pin="RESET" pad="22"/> <connect gate="G$1" pin="RXI" pad="2"/> <connect gate="G$1" pin="TXO" pad="1"/> <connect gate="G$1" pin="VCC" pad="21"/> </connects> <technologies> <technology name=""/> </technologies> </device> </devices> </deviceset> </devicesets> </library> </drawing> </eagle> Micro | Arduino Documentation | Pin | Signal
Because the Pro Micro is open-source, you don’t have to draw it yourself.
As he dropped the component onto his schematic, it felt like the first gear finally clicking into place. In the Schematic View