ESP8266

1. GPIO15 -> GND with 4.7k resistor (10k might be fine too)
2. EN -> 3.3v with 10k resistor
3. GPIO0 -> GND to flash/program
4. GPIO0 -> 3.3v to run normally

I2C OLED

1. OLED SDA -> GPIO4
2. OLED SCK -> GPIO5

NRF24L01

1. RF SCK -> GPIO14
2. RF MISO -> GPIO12
3. RF MOSI -> GPIO13
4. RF CE -> GPIO16
5. RF CSN -> GPIO15 (and to GND via 4.7k resistor)

Use https://github.com/rpakdel/arduino-nrf24-basic/tree/master/sender for sender

Note: Uploading to ESP8266 at higher rates than 115200 doesn't work anymore for me with the NRF24L01 connected.

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