SirenAlti
Firmware updates
Firmware updates for SirenAlti are as simple as dragging the firmware file below onto a USB drive. Follow these steps:
Firmware Version 1.8 (September 24, 2026)
Fixes the buttons not responding right after a firmware update until the reset button was pressed. A factory reset now fully returns the unit to its shipping state. Also includes the 1.6 fix that cut standby battery drain from about 230 µA to about 11 µA: the storage chip was never fully going to sleep between jumps, which is why a charged unit lost most of its battery in a week. Recommended for every unit.
SirenAlti_Firmware_1_8.uf2
- 1. Download the latest firmware file below.
- 2. Plug the altimeter into a computer using a data USB cable. Not all USB cables carry data; all cables we sell or include with altimeters do.
- 3. Using a paperclip, give the reset button between the two buttons a quick double click. It is important that the double click is fast. Do not hold down either button while doing this.
- 4. The altimeter appears on the computer as a USB drive named FDS ALTI. Drag the new firmware file onto it.
- 5. You will often see a failure message from the computer, because the altimeter disconnects itself once the update is applied. This is normal. Confirm the update by connecting to the FDS Altis app and checking the firmware version under Info.
Firmware Version 1.8 (September 24, 2026)
Fixes the buttons not responding right after a firmware update until the reset button was pressed. A factory reset now fully returns the unit to its shipping state. Also includes the 1.6 fix that cut standby battery drain from about 230 µA to about 11 µA: the storage chip was never fully going to sleep between jumps, which is why a charged unit lost most of its battery in a week. Recommended for every unit.
SirenAlti_Firmware_1_8.uf2