GBA Assembly — 1. How the hardware works
Start from scratch: understand the Game Boy Advance CPU, ROM, RAM and memory map before writing your first instructions.
Read articleAlan Jahnel / Software engineering
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GBA Assembly — 2. Bits, registers and memory
Follow values through ARM assembly: bits, addresses, loads, stores, comparisons and masks, with step-by-step exercises.
Read articleGBA Assembly — 3. Your first ROM
Set up the tools and build a complete ROM that fills the screen and lights up one pixel. Understand every step from text to hardware.
Read articleGBA Assembly — 4. Pixels, colors and rectangles
Learn how coordinates become VRAM addresses and how five-bit RGB colors form a rectangle in Mode 3.
Read articleGBA Assembly — 5. Timing, VBlank and animation
Make a square blink in sync with the display and understand VCOUNT, VBlank, polling and the difference between a frame and a CPU instruction.
Read articleGBA Assembly — 6. Reading the buttons
Read KEYINPUT, interpret active-low bits and make a square change color. Learn to distinguish pressing a button from holding it down.
Read articleGBA Assembly — 7. Moving a square
Combine input, a position in RAM and drawing to move a square, respect screen boundaries and erase the previous image without leaving trails.
Read articleGBA Assembly — 8. Your first mini-game
Move a square to a target and create a win condition. Understand rectangle overlap, game state and restarting with the Start button.
Read articleGBA Assembly — 9. From examples to Tower Defense
Learn to investigate failures and connect the hardware examples to the main Tower Defense tutorial, with a reading guide and next steps.
Read articleGBA Assembly: instruction and syntax reference
Look up ARM7TDMI instructions, registers, flags, conditions, addressing, the stack and directives, with examples and links to the series.
Read articleA Game Boy Advance tower defense in assembly, from scratch
Build a Game Boy Advance tower defense in assembly: four stages, commented code and a reproducible ROM made from three files.
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