Section 2: Display Control37
01234 Flag Status Annunciator
If flags 0, 1, 2, 3, or 4 are set in a program or from the keyboard, the corresponding display annunciator turns on. A flag annunciator showing in the display indicates a set (true) flag. Don’t worry about flags yet—they are covered in detail later in this handbook.
Shift Key Annunciator
Any time you press the g (shift) key, the SHIFT annunciator turns on. The annunciator turns off again when you press g or the shifted function is executed.
PRGM (Program) Mode Annunciator
Pressing PRGM places the HP-41C into PRGM (program) mode and turns on the PRGM annunciator. Pressing PRGM again takes the calculator out of PRGM mode and turns off the annunciator. PRGM mode and programming are covered in part II of this handbook, so don’t be concerned about the PRGM annunciator now.
ALPHA (Alphabetic) Mode Annunciator
When you place the HP-41C into ALPHA mode by pressing ALPHA , the ALPHA annunciator turns on. When the ALPHA annunciator is turned on, you are assured that the ALPHA keyboard is active. The ALPHA keyboard was covered in section 1, pages 18-20.
The convenience of the HP-41C display annunciators allow you to concentrate on the problem at hand—there is no need to remember the status of the calculator. Just look at the display; you can immediately see all HP-41C operation conditions.