For anyone interested I wrote a small utility which generates the full TL866A firmware, based on custom serial. The software allows and firmware update (like minipro but with more options). For full firmware upgrade you will need an pic programmer and firmware hex file generated by this utility; for regular upgrade you will need the update.dat file from minipro software and this software utility. If you have Windows XP make sure you have installed net framework (at least version 2.0). The software is not finished yet, but if someone wants to try it is ok, because I have not enough time available.
Sugestions, questions and opinions are welcome, thank you.
Updated: May 08,2013. Fixed minor bugs, please redownload.
Updated May 16,2013. Fixed schematic diagram drawing mistake.
Updated November 23,2013. Introduced firmware dump option.
Updated November 25,2013. Introduced CS firmware generator.
Updated November 30,2013. New version.
Updated February 8,2014. New version.
Updated May 5,2016. New version.TL866 firmware updater