ti-basic

TI-BASIC: Why are there question marks in a menu?


I'm writing a program in TI-BASIC, for use on the TI-84+CSE, which begins with a Menu( operator for simplicity when it comes to choosing a branch. The menu, when the program is executed, displays question marks (?) for the final two elements which I have not designed as such. From what I can tell, the syntax of the menu is correct, and thus should not display anything abnormal, yet when I run the program, the final two options are displayed as question marks and when I press 9 to access that option, the calculator displays a label error, despite the correct label appearing on the next line. I have not yet tested the other 8 options, as I would first like to resolve this issue before continuing on to the rest of the program. As a side note, this program is one of many branching subprograms that high school STEM curricula in one place.

An equivalent version of the entire program. Storing 999.999 to A is my method of telling the calculator the user wanted to return to the previous screen, as the whole process is divided into 15 subprograms, and navigating between isn't as simple as using Goto Lbl.

Menu("Title","A",A,"B",B,"C",C,"D",D,"E",E,"F",F,"G",G,"H",H,"<Back",EX)
Lbl EX
999.999→A

This is what the menu looks like when I run the program, with the letters A through H replacing the labels and text in the actual program, while keeping everything else identical:

Title
1 A
2 B
3 C
4 D
5 E
6 F
7 G
8 ?
9 ?

Solution

  • TI-Basic's Menu command is limited to 7 options on standard devices

    It is 9 for colour calculators, but 7 otherwise.

    Source: http://tibasicdev.wikidot.com/menu

    Workaround

    Give 6 options + a "Next" option that opens up 6 more, etc.