Instructor Notes

February 20, 2008

quote

"It's easier to ask forgiveness than it is to get permission." (Grace Hopper 1986)

Assignments

• Hello Sprite: due March 2 midnight
• Hello Noise
• Term Project proposals etc.

Review

• Hello I/O
  • gbspec lines 1016 to end of document
  • I/O registers from $FF00 to $FF4B, and $FFFF (gbspec.txt lines 1016 to the end)
    • timer, read joy pad, serial data, sound, video modes, window placement, etc.
• video:
  • background tile map
  • tile pattern table

Sprites

• see GameBoy video tutorial

• sprite bug (gbspec.txt lines 770-790)
  • use incdecss.inc and the inc/dev macros to prevent this

Assembler commands

• help: asm.htm
• MACRO: asm/macro.htm
• SET, PRINT, RSSET, HOME, BSS, .labels (see line 101 in hello-world.asm for example),
• walkthrough of hello-sprite.inc:

  • LoByteVar sort of like declaring variables in c

  • declaration of a structure
• show docs for rgbds

Hello Sprite No Interrupts

• walkthrough

Interrupts

• define Interrupt

• Z80 Interrupt vector not on the GameBoy

• interrupt addresses: gbspec.txt lines 156-180
  • vblank
  • timer (rTMA, rTAC (gbspec lines 1137 - 1155)

  • serial transfer (for connecting multiple GameBoys, for example)

for another class

• instruction types
• more on addressing modes (TRS-80 book page 41 chap 3)