GitHub - tinygo-org/espflasher: Go CLI and library for flashing firmware to Espressif ESP8266 and ESP32-family microcontrollers

go install tinygo.org/x/espflasher@latest

# Install
go install tinygo.org/x/espflasher@latest

# Flash a single binary
espflasher -port /dev/ttyUSB0 firmware.bin

# Flash with specific offset and chip
espflasher -port /dev/ttyUSB0 -offset 0x10000 -chip esp32s3 app.bin

# Flash via native USB-JTAG/Serial (ESP32-S3, ESP32-C3, etc.)
espflasher -port /dev/ttyACM0 -reset usb-jtag -chip esp32s3 firmware.bin

# Flash multiple images (bootloader + partitions + app)
espflasher -port /dev/ttyUSB0 \
    -bootloader bootloader.bin \
    -partitions partitions.bin \
    -app application.bin

# Erase flash before writing
espflasher -port /dev/ttyUSB0 -erase-all firmware.bin

go get tinygo.org/x/espflasher/pkg/espflasher

package main

import (
    "fmt"
    "log"
    "os"

    "tinygo.org/x/espflasher/pkg/espflasher"
)

func main() {
    // Connect to the ESP device
    flasher, err := espflasher.New("/dev/ttyUSB0", nil)
    if err != nil {
        log.Fatal(err)
    }
    defer flasher.Close()

    fmt.Printf("Connected to %s\n", flasher.ChipName())

    // Read the firmware binary
    data, err := os.ReadFile("firmware.bin")
    if err != nil {
        log.Fatal(err)
    }

    // Flash with progress reporting
    err = flasher.FlashImage(data, 0x0, func(current, total int) {
        fmt.Printf("\rFlashing: %d/%d bytes (%.0f%%)", current, total,
            float64(current)/float64(total)*100)
    })
    if err != nil {
        log.Fatal(err)
    }
    fmt.Println()

    // Reset the device to run the new firmware
    flasher.Reset()
    fmt.Println("Done!")
}

go get tinygo.org/x/espflasher/pkg/nvs

import "tinygo.org/x/espflasher/pkg/nvs"

entries := []nvs.Entry{
    {Namespace: "wifi", Key: "ssid", Type: "string", Value: "MyNetwork"},
    {Namespace: "wifi", Key: "channel", Type: "u8", Value: uint8(6)},
    {Namespace: "config", Key: "timeout", Type: "u16", Value: uint16(3000)},
    {Namespace: "config", Key: "name", Type: "string", Value: "MyDevice"},
}

partition, err := nvs.GenerateNVS(entries, nvs.DefaultPartSize)
if err != nil {
    log.Fatal(err)
}
// partition is a []byte ready to flash at the NVS partition offset

entries, err := nvs.ParseNVS(partitionData)
if err != nil {
    log.Fatal(err)
}
for _, e := range entries {
    fmt.Printf("[%s] %s = %v\n", e.Namespace, e.Key, e.Value)
}

// With default options (115200 baud, auto-detect, compressed)
flasher, err := espflasher.New("/dev/ttyUSB0", nil)

// With custom options
opts := espflasher.DefaultOptions()
opts.FlashBaudRate = 921600
opts.ChipType = espflasher.ChipESP32S3
opts.Logger = &espflasher.StdoutLogger{W: os.Stdout}
flasher, err := espflasher.New("/dev/ttyUSB0", opts)

// For boards with native USB-JTAG/Serial (ESP32-S3, ESP32-C3, etc.)
opts.ResetMode = espflasher.ResetUSBJTAG
flasher, err := espflasher.New("/dev/ttyACM0", opts)

data, _ := os.ReadFile("firmware.bin")
err := flasher.FlashImage(data, 0x0, progressCallback)

images := []espflasher.ImagePart{
    {Data: bootloaderBin, Offset: 0x1000},
    {Data: partitionsBin, Offset: 0x8000},
    {Data: applicationBin, Offset: 0x10000},
}
err := flasher.FlashImages(images, progressCallback)

// Erase entire flash
err := flasher.EraseFlash()

// Erase a specific region (must be sector-aligned)
err := flasher.EraseRegion(0x10000, 0x100000)

// Read a hardware register
val, err := flasher.ReadRegister(0x3FF00050)

// Hard reset the device
flasher.Reset()