Casio fx-50F/fx-50FH programming

[Dave Britten]

I scored a dirt cheap Casio fx-50FH to play around with, and I've been seeing what I can do with its very limited programming capabilities. Here's some of the more noteworthy features (or lack thereof):

- Can store four programs, 680 bytes total
- NO subroutines; you can't call one program from inside another
- Has labels and goto, but also some structured programming: While and For loops with Break, and If/Then/Else, though you can't seem to nest loops
- Only 7 variables (A, B, C, D, X, Y, M), with no indirect addressing; can use M+ and M- to directly increment/decrement M
- No prompt messages; when getting user input, it displays a simple prompt like "X?"

I won't describe all its math capabilities - it's a pretty typical solar-powered Casio, with complex math, 1 and 2 variable stats, etc. - but it's worth mentioning that it has NO integer/fractional part functions. It does at least have a rounding function, which gave me enough to write a simple prime factor finder (trial division by 2 and sequential odd numbers, no mod-30 sieve here):

Code:

3→M
?→X
Fix 0
While X÷2=Rnd(X÷2)
X÷2→X
2◢
WhileEnd
Lbl 1
X=1⇒Goto 9
M²≥X⇒X→M
While X÷M=Rnd(X÷M)
X÷M→X
M◢
WhileEnd
2M+
Goto 1
Lbl 9
Norm 1

Replace the "Norm 1" at the end with your choice of display mode to return to after running the program.

This is definitely one of the least capable programmables I've seen from Casio; you're better off buying just about any other programmable model they've ever made.