The CASIO FX-850p series
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 The main device of this series to save programs and print is the Casio FA-6.Watch device : FA-6

 To print to a Casio FP-40 printer, use SB-44 interface.Watch device : SB-44

 A BASIC program to solve sudoku.

 Runs on all for lines machines of the series.

 A trick for transferring programs from FX-850p to 880p.

 Thanks to Patrice for this trick.

 Tested successfully between a VX4 and a VX3: a piece of telephone wire (3 strands) and pins for the connection.
 Same test between a Z1 and a Z1GR.

 The essential tools of Marcus to read sound files from the FP-6 interface and convert them into text file (and vice versa).