Section 10: The Index Register and Loop Control 109
To Labels.
If the R
I
value is
positive
,
t
V
and
G
V
will
transfer execution to the
label
which corresponds to the number in the Index
register (see the above table).
For instance, if the Index register contains 20.00500, then a
tV
instruction will transfer program execution to
´b
A
. See the chart
on page 107.
To Line numbers.
If the R
I
value is
negative,
tV
causes branching
to that
line number
(using the absolute value of the integer portion of the
value in R
I
).
For instance, if R
I
contains –20.00500, then a
tV
instruction will
transfer program execution to program line 020.
Indirect Flag Control With
V
F
V
,
"
V
, or
?
V
will set, clear, or test the flag (0 to 9)
specified in R
I
(by the magnitude of the integer portion).
Indirect Display Format Control With
V
´
•
V
,
´
i
V
, and
´
^
V
will format the
display in their customary manner (refer to pages 58–59), using the number
in R
I
(integer part only) for
n
, which must be from 0 to 9.
*
Loop Control With Counters:
I
and
e
The
I
(
increment and skip if greater than
) and
e
(
decrement and
skip if less than or equal to
) functions control loop execution by referencing
and altering a loop
control number
in a given register. Program execution
(skipping a line or not) then depends on that number.
The key sequence is
´
{
I
,
e
}
register number
. This number is
0 to 9, .0 to .9,
V
,or
%
.
The Loop Control Number.
The format of the loop control number is:
nnnnn.xxxyy,
where
±
nnnnn
is the current counter value,
xxx
is the test (goal) value, and
yy
Is the increment of decrement value
*
Except when using
f
(section 14)
Summary of Contents for HP-15C
Page 1: ...HP 15C Owner s Handbook HP Part Number 00015 90001 Edition 2 4 Sep 2011 ...
Page 17: ...Part l HP 15C Fundamentals ...
Page 64: ......
Page 65: ...Part ll HP 15C Programming ...
Page 118: ...118 ...
