How I flash my ESP01 device

IOT Jan 25, 2024

I want to use Tasmota in my house more and more, but I don't want to use it on the wemos d1 mini devices, because it must only measure temperatures or other. So I decided to use a smaller device, like the ESP01. This device has ONLY one GPIO port. This is mostly enough for a simple sensor. This device looks like this

But how I can get a Tasmota firmware onto this device? This article will describe it for you.

The Bucketlist

On the bucketlist I hav the an Programmer likt this ESP-01 Flasher This looks like this.

This tool is very cheap and handy to use, just place the esp01 on top of this and you can flash it. But there is one more step to do


Before you can flash the module, you must tell the module to get in the flashing mode, for this you must create a bridge between GPIO0 and GND.

This will set your device in the flashing mode.


How we can flash the firmware onto the device? I use a Linux console and install the ESP Flash tool

sudo apt install esptool

This command will install the ESPTool from espressif. This tool will be used to upload the firmware onto the ESP01 device. Next we need firmware. Let's use it as Tasmota Firmware, let's download this with

uinzip tasmota-4M.bin.gz

Now we have all the required tools to get firmware onto the device.


Don't panic, this is not a complex process, for this, you must execute the following command

esptool --port /dev/serial/by-id/usb-1a86_USB2.0-Ser_-if00-port0 0x0 tasmota-4M.bin

You must adjust the parameters behind the --port, this will define the port where the programmer is logged in. Then you must modify the path to the bin file.

The log output looks then like this: v2.1
Detecting chip type... ESP8266
Chip is ESP8266
Enabling default SPI flash mode...
Configuring flash size...
Erasing flash...
Flash params set to 0x0320
Took 0.06s to erase flash block
Wrote 726016 bytes at 0x00000000 in 74.1 seconds (78.4 kbit/s)...

Hard resetting...

After that, the firmware is completely uploaded!

Final words

Yes, this was a small blog post about basic knowledge, but I think this would be helpful for other guys. Now you will be able to flash the ESP-01 device with your custom firmware. So now it's your turn! What are your plans with your ESP-01 and which firmware do you want to use?