HP 30b Professional, 20b Consultant Financial manual Tests and Jump Functions, 8= LBL

Tests and Jump Functions

When creating a program, there is often a need for the conditional execution of an instruction based on a specific condition, as well as the repetition of a set of instructions.

This is handled on the HP 30b using the GOTO, LBL (label) and Test instructions. LBL is an instruction that does not do anything by itself, but it acts as a marker for Jump instructions.

1.To enter a label or GOTO instruction, press and hold :and simultaneously press the GOTO, GOTOT, or GOTOF key, then release both keys.

2.Type a number between 00 and 99 (for numbers smaller than 10, you must type the 0 first, such as 03).

3. For example, (HOLD) creates label 03 in your program. You can

then use a GOTO 03 instruction to jump to that label from any location in your program to the position of the label. GOTOT (Go To If True) and GOTOF (Go To If False) will only jump if the current displayed number is non-0 (true) for GOTOT or 0 (false) for GOTOF.

Used together, these instructions allow you to create programs like the following:

8= LBL 01

DISP 5

-1=

GOTOT 01 STOP

Use the following keystrokes to enter the program:

1.		(HOLD)
2.	(HOLD)
3.			(HOLD)

4. (HOLD) . This program has 13 bytes, and the checksum is 234. This program counts from eight to zero displaying each number 1 second.

Programming 81