CEM26/GEM28 Firmware

Firmware for CEM26 and GEM28 Mount (5/23/2023)

No firmware upgrade is needed if your mount works properly.

Please read the Release Notes before performing any firmware upgrades. Follow the Upgrade Instruction carefully. Loading the wrong file into the system may cause the mount inoperable!


Encoder calibration is needed for a mount with a high precision encoder (EC version) after the firmware upgrade.

CEM26/GEM28 firmware upgrade instruction
iOptron Upgrade Utility V2.23 (Need this latest version)
CEM26/GEM28 Firmware Package (incl. 8409 V1 HC) (V230305)
FTDI VCP Driver, or go to FTDI Chip website to download the VCP driver
CEM26/GEM28 Firmware Upgrade History