**[arch3/_private/calc1_ahdr.htm]**## Re: Instructions for Olivetti Divisumma28

**From: **Katie

**Email: **

### Comments

The Divisumma 18 and 28 use a sort of "adding machine" logic, as it's sometimes called.
Start with the T key. It will print and clear the total.
Punch in the number to add or subtract and hit the + or - key.
Hit the S key to print the total without clearing it.
To multiply or divide: punch in the first number, hit the divide/times key, punch in the second number then press the corresponding = key (the one with the matching color). This will print the answer and clear the total.
If you make a mistake while punching in a number hit the C key and do it again.
The switch with the numbers 0,2,3,4 on it sets the number of decimal places printed.

**[arch3/_private/calc1_aftr.htm]**