Frank,

This is rather strange.

Try typing 'RAM', before entering your program.

BASIC52 uses internal data memory locations 13H and 14H to hold the start address of the current BASIC program - check that these hold $02 and $0 respectively (use the DBY function to print these out).

Also check that external program location 2002H does not contain the value 5AH, since this causes BASIC52 to check for extra, user defined, tokens.

It would also be interesting to use the XBY function to 'poke' a valid line of code directly into the RAM space to see if this would then appear with a LIST command.

Hope this helps,
Derek.