To check the current version of the firmware installed on your TK-Talkie, follow these steps:
Updating the firmware on your TK-Talkie consists of the following steps:
BEFORE YOU BEGIN: If you are updating from V3 to V4, you will need to convert your settings files to the new format before you start. Please read and follow the instructions on the file conversion page. In addition, you will need to download and install the V2 mobile app to communicate with the V4 firmware.
Download the installer for your operating system (Windows/Mac/Linux) from the Teensy Loader download page. Please be sure to read the instructions on the download page regarding installing and running the application.
Once you have installed and opened the application, you should see the following:
Connect your TK-Talkie to your computer or laptop via a micro-USB cable.
PLEASE NOTE: Not all USB cables are the same! Some are just for providing power, and others have both power and serial communications capability. You will need a USB cable that has serial capability. Cables that come with your phone, for example, have serial capability. Most cheap USB cables only provide power. Check the opening of the larger plug on your USB cable and you should see four (4) metal strips (This is no guarantee, however. If the Teensy Loader does not see your TK-Talkie, it is most likely an incorrect cable.)
Click on "File -> Open HEX File" and locate the firmware file you just downloaded (make sure you have unzipped it.)
PLEASE NOTE: If after loading the firmware you see a message "Too Large!" you can just ignore it.
In order to put your TK-Talkie into programming mode, you'll need to press the programming button located at the back of the TK-Talkie above the SD card slot.
Once you press the programming button, the arrows on the Teensy loader should light up.
Click the arrow pointing down to being the download. You should see the upload progress. When finished, you will see a "Download Complete" message.
To reboot your TK-Talkie, you can either click the arrow pointing right on the Teensy Loader or you can unplug the USB cable and plug it back in to recycle the power.
If you had to remove the lid on your TK-Talkie, you can replace it now.
Connect to your TK-Talkie with the mobile app and check the firmware version as described above.