the little person computer is a model to learn about computer architecture

# architecture

is uses the decimal system, with words of three-digits each.

it has ten instructions and 100 memory addresses.

# example programs

written in the corresponding assembly language.

as part of the s-camino practice.

## multiplication of two numbers

### no labels

pure assembler version, no labels.

- 15 is the address for the result
- 16 is the address for 'a'
- 17 is the addres for 'b'

INP STA 16 INP STA 17 BRZ 11 LDA 16 ADD 15 STA 15 LDA 17 SUB 14 BRA 3 LDA 15 OUT HLT DAT 1 DAT 0 DAT 0 DAT 0

### with labels

the same behavior as above, but using labels for easier programming and reading

inputs INP STA a INP loop STA b BRZ print // finish if b is 0 LDA a ADD result STA result LDA b SUB one BRA loop print LDA result OUT HLT one DAT 1 result DAT 0 a DAT 0 b DAT 0

# external links

little man computer - cpu simulator