The FIX32F directive causes the C166 Compiler to alter the
coding of MOV Rx,[Ry+const16] instruction sequences.
Some early Flash devices variants with 256KB Flash Memory have
problems with the MOV Rx,[Ry+const16] addressing. This sequences must
be replaced with the following:
[ATOMIC #3] ;; in case of Ry == R0
If you use a device with this chip problem you require a
modified C166 run-time library. This run-time library can be found
in the \Keil\C166\LIB\FIX folder. Enter this library path in
μVision under Project — File Extensions, Books, Enviornment —
Environment — LIB Folder.