Continue the program.

!=

Note that when program execution is suspended by PROMPT, you can execute calculator operations just as you did before you started the program. If the outer radius b of the torus in the previous example is measured as 0.83 feet,

you can convert that value to inches while the program is suspended for data input by pressing .83 `12 *, then

!=.

Using DISP FREEZE HALT, CONT for Input

DISP FREEZE HALT lets you control the entire display during input, and allows the user to use normal keyboard operations during input.

To enter DISP FREEZE HALT in a program:

1.Enter a string or other object to be displayed as a prompt.

2.Enter a number specifying the line to display it on.

3.Enter the DISP command (PRG OUT menu).

4.Enter a number specifying the areas of the display to “freeze.”

5.Enter the FREEZE command (PRG OUT menu).

6.Enter the HALT command (PRG OUT menu).

« promptobject displayline DISP freezearea FREEZE HALT »

DISP displays an object in a specified line of the display. DISP takes two arguments from the stack: an object from level 2, and a displayline number 1 through 7 from level 1. If the object is a string, it’s displayed without the "" delimiters. The display created by DISP persists only as long as the program continues execution — if the program ends or is suspended by HALT, the calculator returns to the normal stack environment and updates the display. However, you can use FREEZE to retain the prompt display.

FREEZE “freezes” display areas so they aren’t updated until a key press. Argument n in level 1 is the sum of the codes for the areas to be frozen: 1 for the status area, 2 for the stack/command line area, 4 for the menu area.

HALT suspends program execution at the location of the HALT command and turns on the HALT annunciator. Calculator control is returned to the keyboard for normal operations.

When execution resumes, the input remains on the stack as entered.

To respond to HALT while running a program:

1.Enter your input — you can use keyboard operations to calculate the input.

2.Press !=.

Example: If you execute this program segment

«"ABCDEFGHI" CLLCD 3 DISP 2 FREEZE HALT »

The display looks like this:

RPL Programming 139

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HP 48gII Graphing, 50g Graphing manual Using Disp Freeze HALT, Cont for Input, To enter Disp Freeze Halt in a program