diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/interrupts.s (renamed from src/vectors.s) | 69 | ||||
| -rw-r--r-- | src/jetpac.s | 67 |
2 files changed, 66 insertions, 70 deletions
diff --git a/src/vectors.s b/src/interrupts.s index e5d1a58..8c53af7 100644 --- a/src/vectors.s +++ b/src/interrupts.s @@ -1,74 +1,5 @@ -.segment "VECTORS" - .addr nmi, reset, irq - .segment "CODE" -;; Debug utilities. -.scope Debug - ;; Counter for frame drops. Only touched when PARTIAL is defined. - zp_frame_drops = $90 ; asan:ignore -.endscope - -;; Pretty standard reset function, nothing crazy. -.proc reset - ;; Disable interrupts and decimal mode. - sei - cld - - ;; Disable APU frame counter. - ldx #$40 - stx APU::m_frame_counter - - ;; Setup the stack. - ldx #$FF - txs - - ;; Disable NMIs and the APU's DMC. - inx - stx PPU::m_control - stx PPU::m_mask - stx APU::m_dmc - - ;; First PPU wait. - bit PPU::m_status -@vblankwait1: - bit PPU::m_status - bpl @vblankwait1 - - ;; Initialize the counter for frame drops before any NMIs can come in. - .ifdef PARTIAL - lda #0 - sta Debug::zp_frame_drops - .endif - - ;; Reset all sprites by simply moving the Y coordinate out of screen. - lda #$EF - ldx #0 -@sprite_reset_loop: - sta OAM::m_sprites, x - inx - inx - inx - inx - bne @sprite_reset_loop - - ;; DMA setup for sprite reset. - lda #$00 - sta OAM::m_address - lda #$02 - sta OAM::m_dma - - ;; Second PPU wait. After that the PPU is stable. -@vblankwait2: - bit PPU::m_status - bpl @vblankwait2 - - ;; NOTE: palettes are not initialized here as it's going to be one of the - ;; first things done on `main` code. - - jmp main -.endproc - .proc nmi ;; Should we skip it? bit Globals::zp_flags diff --git a/src/jetpac.s b/src/jetpac.s index 16fa292..79fec84 100644 --- a/src/jetpac.s +++ b/src/jetpac.s @@ -36,6 +36,7 @@ .include "../include/asm.s" .include "../include/joypad.s" .include "../include/globals.s" +.include "../include/debug.s" .include "assets.s" .include "background.s" @@ -45,7 +46,68 @@ .include "enemies.s" .include "title.s" .include "driver.s" -.include "vectors.s" +.include "interrupts.s" + +;; Pretty standard reset function, nothing crazy. +.proc reset + ;; Disable interrupts and decimal mode. + sei + cld + + ;; Disable APU frame counter. + ldx #$40 + stx APU::m_frame_counter + + ;; Setup the stack. + ldx #$FF + txs + + ;; Disable NMIs and the APU's DMC. + inx + stx PPU::m_control + stx PPU::m_mask + stx APU::m_dmc + + ;; First PPU wait. + bit PPU::m_status +@vblankwait1: + bit PPU::m_status + bpl @vblankwait1 + + ;; Initialize the counter for frame drops before any NMIs can come in. + .ifdef PARTIAL + lda #0 + sta Debug::zp_frame_drops + .endif + + ;; Reset all sprites by simply moving the Y coordinate out of screen. + lda #$EF + ldx #0 +@sprite_reset_loop: + sta OAM::m_sprites, x + inx + inx + inx + inx + bne @sprite_reset_loop + + ;; DMA setup for sprite reset. + lda #$00 + sta OAM::m_address + lda #$02 + sta OAM::m_dma + + ;; Second PPU wait. After that the PPU is stable. +@vblankwait2: + bit PPU::m_status + bpl @vblankwait2 + + ;; NOTE: palettes are not initialized here as it's going to be one of the + ;; first things done on `main` code. + + __fallthrough__ main +.endproc + .proc main ;; Disable the PPU and zero out variables which shadow PPU registers. @@ -148,3 +210,6 @@ ;; TODO: allow to start over, reset flags, control register, etc. jmp @over .endproc + +.segment "VECTORS" + .addr nmi, reset, irq |