From 03a5882df17ea42aa0b4039173f85ea1e7ce99fe Mon Sep 17 00:00:00 2001
From: Miquel Sabaté Solà <mssola@mssola.com>
Date: Fri, 13 Feb 2026 00:03:07 +0100
Subject: Remove vector.s
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Instead of this, the 'reset' function can go into 'jetpac.s', as we
could consider it's part of the 'main' work. As a bonus, doing this
alignment gives us 3 bytes back from ROM space. Not that we care too
much about space, but it's amusing nonetheless.

The debug scope has been moved into its own file in include/. Admittedly
it's not the most crucial file in the project, but it makes things more
logical and it opens the door to more debugging utilities.

This leaves us with a vector.s file only containing interrupt
code. Thus, it just makes sense to rename it to interrupts.s, which in
the end makes things more organized.

Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>
---
 src/jetpac.s | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 66 insertions(+), 1 deletion(-)

(limited to 'src/jetpac.s')

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
-- 
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