# Firmware update for the Teensy microcontroller

**URL:** <https://smallbasic.discourse.group/t/firmware-update-for-the-teensy-microcontroller/70>\
**Category:** News\
**Tags:** teensy\
**Created:** [September 27, 2026, 7:37pm UTC](https://smallbasic.discourse.group/t/firmware-update-for-the-teensy-microcontroller/70 "2026-09-27T19:37:33Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![J7M](https://yyz2.discourse-cdn.com/free1/user_avatar/smallbasic.discourse.group/j7m/32/7_2.png) [@J7M](https://smallbasic.discourse.group/u/J7M)\
**Post date:** [September 27, 2026, 7:37pm UTC](https://smallbasic.discourse.group/t/firmware-update-for-the-teensy-microcontroller/70/1 "2026-09-27T19:37:33Z")

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The Teensy microcontroller got a firmware update 🙂

1. Persistent flash memory
2. Flash memory file handling
3. Autostart from flash
4. Built in SD Card file handling (Teensy 4.1)

Here a small example:

```auto
import teensy
const fs = teensy.fs
const FS_WRITE = 1

file = fs.open("flash:/test.txt", FS_WRITE)
file.write("test\n")
file.close()

```

You can upload [console.bas](https://github.com/smallbasic/SmallBASIC/blob/master/src/platform/teensy/samples/SerialTerminal.bas) to the Teensy to get a command line interface with commands like ls, cd or cp to manage your files. Type “help” to get a list of all available commands.

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**Author:** ![Tinine](https://avatars.discourse-cdn.com/v4/letter/t/d9b06d/32.png) [@Tinine](https://smallbasic.discourse.group/u/Tinine)\
**Post date:** [September 28, 2026, 10:47am UTC](https://smallbasic.discourse.group/t/firmware-update-for-the-teensy-microcontroller/70/2 "2026-09-28T10:47:47Z")

</div>

I am convinced that I have psychic powers 😁

I just KNEW that there would be a Teensy update, today. 👍 😎