diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/driver.s | 59 | ||||
| -rw-r--r-- | src/interrupts.s | 6 |
2 files changed, 63 insertions, 2 deletions
diff --git a/src/driver.s b/src/driver.s index 2b61e17..536f4e0 100644 --- a/src/driver.s +++ b/src/driver.s @@ -44,6 +44,11 @@ ;; of RAM left. zp_moved_out = $38 + ;; Whether the pause message on the HUD has to be toggled. Like + ;; 'zp_moved_out', maybe a waste of resource to dedicate a full byte for + ;; this, but we have plenty of RAM left. + zp_pause_toggle = $39 + ;; Switch from the title screen to the main screen. Note that this function ;; is to be called with the PPU disabled. If that's not the case, then it ;; will set the proper values to disable it on the next `nmi` call and set @@ -148,11 +153,11 @@ jsr Enemies::init jsr Explosions::init - ;; Initialize pause timer and whether sprites have been moved out of the - ;; screen. + ;; Initialize pause timer and some boolean values. lda #0 sta zp_pause_timer sta Driver::zp_moved_out + sta Driver::zp_pause_toggle ;; Initialize variables for sprite cycling. sta zp_next_bullet_cycle @@ -183,6 +188,10 @@ lda #PAUSE_TIMER_VALUE sta zp_pause_timer + ;; Toggle the message on the HUD. + lda #1 + sta Driver::zp_pause_toggle + ;; Pause vs unpause. lda #%00001000 and Globals::zp_flags @@ -519,4 +528,50 @@ rts .endproc .endif + + ;; Toggle the "Paused" message from the (not quite) HUD. + ;; + ;; NOTE: only call this function from NMI code. + .proc hud_toggle_pause + lda #%00001000 + and Globals::zp_flags + bne @paused + + ;; Clear out the "Paused" message. + bit PPU::m_status + lda #$28 + sta PPU::m_address + lda #$8D + sta PPU::m_address + lda #0 + sta PPU::m_data + sta PPU::m_data + sta PPU::m_data + sta PPU::m_data + sta PPU::m_data + sta PPU::m_data + rts + + @paused: + bit PPU::m_status + lda #$28 + sta PPU::m_address + lda #$8D + sta PPU::m_address + + lda #$2A ; P + sta PPU::m_data + lda #$1B ; A + sta PPU::m_data + lda #$2F ; U + sta PPU::m_data + lda #$2D ; S + sta PPU::m_data + lda #$1F ; E + sta PPU::m_data + lda #$1E ; D + sta PPU::m_data + + rts + .endproc .endscope diff --git a/src/interrupts.s b/src/interrupts.s index 522ee9e..e909d17 100644 --- a/src/interrupts.s +++ b/src/interrupts.s @@ -24,6 +24,12 @@ lda #$02 sta OAM::m_dma + ;; Toggle pause message from the HUD. + lda Driver::zp_pause_toggle + beq @increase_rand + jsr Driver::hud_toggle_pause + +@increase_rand: ;; Increase the random seed. inc Prng::zp_rand |