HP HP-11C User Manual

128 Section 9: The Index Register
Incrementing and Decrementing the Index Register. The
(increment, then skip if greater) and (decrement, then
skip if less than or equal) functions use the loop control number you
place in the Index register.
Both and interpret and compare the components of the
loop control number according to the following format:
+nnnnn is the current counter value,
nnnnn.xxxyy, where XXX is the counter test value, and
A is the increment or decrement
value.
nnnnn is the integer portion of the control number and is used for
counting successive iterations of a program loop, for determining
when to exit from a loop, and for indirectly addressing branches,
subroutines, and storage registers. nnnnn can be from 1 to 5 digits
and, if unspecified, defaults to zero. nnnnn is incremented or
decremented by executions of or [DSE].
Example of Loop Control Number
nnNNNn XXX yy
o ov; 002
Begin Count Count
at zero up to 50 by two’s
xxX is in the decimal portion of the control number. When you use
or to increment or decrement nnnnn, xxx is then
compared internally to nnnnn by the calculator to determine when
the desired number of increments or decrements have been
executed. xxx must be specified as a three-digit number. For
example, an xxx value of 10 would be specified as 010. (xxx is a
reference value and is not changed by executions of or [DSE].)
yy is also in the decimal portion of the control number. yy tells the
calculator what increments to count in, that is, nnnnn will be
incremented or decremented by the value of yy. A specified yy

HP HP-11C Specifications

General

Brand	HP
Model	HP-11C
Category	Calculator
Language	English