ESP-01 Programmer

This programmer needs a external 3.3V, 0.5A power supply. The VCC pin of the FTDI board is not connected because it can happen that the current it can supply is not enough in some cases, leading to a unstable behaviour.

Schematic:

The RESET function/pin is not working in any of my breakout boards. According to the Datasheet the RESET pin is active low, but it is not working on my breakout boards. The workaround I found is to power-cycle the board every time a reset is needed (including programming).

Board library for Arduino IDE (1.8.13) programming

esp8266/Arduino

Programming

Set the board parameters according to this picture:

Short the jumnper (JP1), hit "upload" then power-cycle the board. The upload should run smoothly. If it does not, activate verbose output for upload, then when you see this line:

Connecting........_____

Power-cycle the board again.

Using I2C

The I2C bus uses GPIO0 and GPIO2, those pins are available on J3 and J4. To enable I2C on those pins, use Wire.begin(0, 2);.

i2c_scanner.ino is an i2c scanner that shows how to use the I2C bus on this board.

Files

• Schematic (PDF)
• 3D board view - That is just a reference to help assembling on a prefboard
• Kicad files

Other resources

• ESP-01 cheat sheet
• ESP-01 Manual - There is a schematic at the end
• ESP-01 example applications