Section 2: Display Control36
After automatically switching from fixed point to scientific notation, the display automatically reverts back to the fixed point display originally selected when new numbers come into the display. Note that automatic switching occurs only between fixed and scientific notation displays—engineering notation display must be selected with the ENG .
Any time the HP-41C must display a single line of information which exceeds the 12-character display, the calculator automatically ‘‘scrolls’’ the line through the display to the left so that you can see the complete line.
The HP-41C display contains seven ‘‘annunciators’’ or key words that tell you the status of the calculator. Each annunciator tells you something about how the calculator is operating at that moment.
BAT (Battery) Low Power Annunciator
If the BAT annunciator is displayed, this means you have about 10-30 days of operating time left (using alkaline batteries). The best thing to do when BAT turns on is to put HP-41C batteries on your shopping list. (Refer to Batteries, page 240). Because the HP-41C uses so little power, the normal battery life should be 9-12 months, depending on the freshness of the batteries installed and how much you use your calculator.
USER Mode Annunciator
When you press the USER key to set the HP-41C to USER mode, the USER annunciator in the display turns on. This lets you know that your customized keyboard has become active. The functions that you have assigned to the keyboard become active and the normal functions on those keys are no longer active. For an introductory discussion of USER mode, turn to operating Keys on page 15. USER mode is covered in detail in section 4.
GRAD-RAD Mode Annunciator
When you execute the GRAD function, the HP-41C is placed in GRADs trigonometric mode and the GRAD annunciator turns on. When you execute the RAD function, the HP-41C is placed in RADians mode and the RAD portion of the display annunciator turns on. Function execution is covered in section 4 and trigonometric modes are covered in detail in section 6.