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Firmware
Contents
Manual
User contributions
Update procedure
The easiest way to upgrade the firmware is via USB. Alternatively you can update via MIDI.
When using MIDI-over-USB the transfer speed can be increased significantly by setting "Milliseconds between buffers" to 20 ms and "Delay after F7" to 20 ms.
Using MIDI-OX
When using MIDI-OX (Windows) to send firmware to the Axe-Fx II, be aware that its default settings may cause a buffer overrun error. Change Low Level I/O Buffers size to 256, and number to 16, and Milliseconds between buffers to 90.
Updating presets after a firmware update
Updated firmware may cause changes in your presets. Read the firmware release notes and verify your presets. Also, major firmware revisions may change the structure of presets. Use Preset Update (Utility > Preset) to update all presets to the new protocol. Usually the firmware release notes will explicitly instruct you to do this if necessary.
Driver control panel
The firmware upgrade option in the Axe II's driver control panel is grayed out. This is normal. Source
Programming language
The firmware is coded in C and assemby. Source
