I finally got around to upgrading my Synthex v2.8 to a 20MHz xtal.
Out came the hair drier to heat up the board and test the thing still worked within tolerance.
Succ-U-Bus worked fine but the AppFWtest.hex didn't...
If you remember I suggested to Dmitri that he could add WDT reset code (enter the bootloader) on receipt of an erase SYS command but it never happened so I supplied the AppFWtest.hex which does a WDT.
Turns out the test code used an old TCNT1 value (line 231 in Succ-U-Bus.c);
Here is a replacement hex for anyone who wants it.
Succ-U-Bus_v07_Replacement_AppFWtest.zip
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