Uploaded December 2021 | Updated September 2026, 2 weeks ago
Demonstration of the undocumented self-test feature of the Casio VX-4 and FX-870P Portable Computer.
The Casio VX-4 Portable Computer was released in 1989 and stands out from many similar pocket computers by including not only the BASIC language but also ‘C’ and Common Algebraic Specification Language, or CASL. Machine code programming was also accessible, however, it was not officially supported. The display is 191x32 pixels, instead of just including pixels for each character position like the FX-880P, however, without standard graphics commands machine code was required to utilise.
The self-test is activated by entering 'SYSTEM *'.
The VX-4 in the video includes the optional RP-8, 8Kb RAM expansion.
See my video about the new aftermarket RP-33 memory upgrade at: youtu.be/B9bYyJGjaDM
For a review of the Casio VX-4 see youtube.com/watch?v=n5LAFKWceGM
----Contents----
0:00 Intro
0:12 Activate Self-test
0:20 Self-test Menu
0:49 LCD Test
1:06 Keyboard Test
3:10 Display Loop
Demonstration of the undocumented self-test feature of the Casio VX-4 and FX-870P Portable Computer.
The Casio VX-4 Portable Computer was released in 1989 and stands out from many similar pocket computers by including not only the BASIC language but also ‘C’ and Common Algebraic Specification Language, or CASL. Machine code programming was also accessible, however, it was not officially supported. The display is 191x32 pixels, instead of just including pixels for each character position like the FX-880P, however, without standard graphics commands machine code was required to utilise.
The self-test is activated by entering 'SYSTEM *'.
The VX-4 in the video includes the optional RP-8, 8Kb RAM expansion.
See my video about the new aftermarket RP-33 memory upgrade at: youtu.be/B9bYyJGjaDM
For a review of the Casio VX-4 see youtube.com/watch?v=n5LAFKWceGM
----Contents----
0:00 Intro
0:12 Activate Self-test
0:20 Self-test Menu
0:49 LCD Test
1:06 Keyboard Test
3:10 Display Loop
