Registers - Singer Friden 1155 Operator's Primer

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3 REGISTERS
The 1155 has two working registers in which numbers are stored and
arithmetic is performed.
UPPER REGISTER
(U)
LOWER REGISTER (L)
The following example illustrates the interaction of the registers.
PROBLEM: 9 + 4
=
?
-KEY (8) - - - - L - - - U - - - - - - - - COMMENTARY------
EJ
~
o
9
9
4
13
13
o
o
o
9
o
o
Both registers are set to zero.
When a number is keyed in, it is
placed in L.
ENTER terminates the entry of a
number and causes it to be printed.
When a new number is entered in L,
the previous number is bumped up
into U.
The number that was in L is added to
the number that was in U and the
result is put into L. Then U is
cleared to zero.
Print the number that is in L. End of
program.*
* A program is a sequence of keystrokes to solve a problem. The above program
is executed manually.
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