1. Introduction Lab1 A crash course in assembler programming
Learn how a processor works!
Decode a coded text passage

2. Lab 1 Procedure calls. Byte and word array indexing, pointers.
Conditional branch instructions.
Simple loops.
Reading/ writing from/to data memory.

3. Branch instruction (part of)
Beq rs rt label
Bne rs rt label
Together with Slt-instruction and $0
enough for first lab.

4. Register conventions (fig A9)
Reg. name Nr Usage
zero Constant 0
at 1 Reserved for assembler
v0 - v Expr. evaluation, function results
a0 - a Argument 1-4
t0 - t Temporary (not saved)
s0 - s Saved Temporary
t8 - t Temporary (not saved)
k0 - k Reserved for OS kernel
gp 28 Pointer to global area
sp 29 Stack pointer
fp 30 Frame pointer
ra 31 Return address

5. Lab 1 register usage
Use only
$sx
$tx
$r0 (=$0)

6. Lab 1 - How to represent characters?
Use the ASCII-code
Complete table at WWW