Rod KM6SN has updated his manual for the KD8CEC firmware for the µBITx that is pretty popular because it requires no hardware mods.
The updates to the manual:
1. incorporate feedback received on the manual, with some new
operating tips
2. enhance the Memory Manager section a bit
3. improve readability.
As before, please send any feedback to the email address shown in the manual. A new manual for KD8CEC firmware rev 1.07 is forthcoming, as is a manual on the Memory Manager.