Week 4 - Lecture

This week's lecture started with how we can display text on the 6502 emulator. I found it fairly easy.
Here is a sample code:

define SCREEN $f000
           ldy #$00
 
 char:     lda text,y
           beq done
           sta SCREEN,y
           iny
           bne char
 
 done:     brk
 
 text:
 dcb "S","P","0","6","0","0",32,"i","s",32,"a","w","e","s","o","m","e",".",00

This was accomplished by having a text as dcb and looping it to load and store it in accumulator.
Spaces were put using number 32 and all characters were put in double quotes.

Next we talked about compiling the code. We compiled a simple C program inside linux and saw its executable was larger than its original file. We also learnt about dynamic and static linking and how each of them have their own pros and cons. While static being larger in size and dynamic was relatively smaller. Then we learnt about different compatibility modes it had to offer and how it could range from O0 (almost no optimizations) to O3 (most optimized) and we were also shown how many flags for optimized content was set to active and how we could manipulate it. Og was used to optimize for debugging. We almost looked upon certain commands like make which could be used to make partial builds inside of whole when small changed are made to source files.

This week's lecture ended with us touching upon something new and we were also told text was the last thing we learnt on 6502 and we wont be working with it anymore.