The CASIO PB-100 series
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 This series includes pockets derived from the PB-100
 Commonalities :

 Size : 165 x 71 x 10 mm

 A 12-digit screen

 a programming language very rudimentary
 They differ one from the other :

 by standard or extended memory (OR-X modules)

 by the addition of an extra function key F

 by the availability of S+EXE combination ("previous" function)

 by the str$( ) function

 by the DATA BANK functions

 The keys are whether black whether white and the hull presents various tints.

 F key

 The F key permits direct access to some mathematicals functions written besides character keys.

 When it is not available, it is possible to add the F key by making a hole on the right of the S key and putting a spare key. This has not been studied on models including Data Banks funtions.Watch programs to download

 The FX models have F Key, the PB ones haven't, like for the PB-410 series.
 The "Previous" key

 On models presenting a little triangle above the Enter key, the S+EXE combination allows to move back in the listing (mode 1).

 On data bank models, this combination allows to edit previous data while editing.
 A special model with a familiar look : the UCOM
 The essential tools of Marcus to read sound files from the FA3 interface and convert them into text file (and vice versa).

 The bernie.hp site and his fabulous simulator.

 Which model appears in thise episode of Magnum (thanks to ?