Hi guys, Been having a bit of trouble converting a small bit of code to use less ram and am getting a very strange effect. Changing this: Code: ; ************************************ ; initialize everything ; ************************************ move.w #1, (tempo) ; initialize tempo move.w #note_start_position_y, (greennote_position_y) ; Set green note's y position move.w #note_start_position_y, (rednote_position_y) ; Set red note's y position move.w #note_start_position_y, (yellownote_position_y) ; Set yellow note's y position move.w #rockindicator_start_position_x, (rockindicator_position_x) ; Set rock indicator's x position ; ****************************************************************** ; Main game loop ; ****************************************************************** GameLoop: ; green note movement code move.w (greennote_position_y), d0 ; green note y position in d0 add.w (tempo), d0 ; add the tempo cmp.w #(note_plane_border_offset-note_bounds_bottom), d0 ; does the player miss the note entirely blt @GreenNoteNotWithinBounds ; branch if the player hasn't move.w #note_start_position_y, d0 ; otherwise the player has so move the note back to the top @GreenNoteNotWithinBounds: move.w d0, (greennote_position_y) ; set the green note's position normally ; red note movement code move.w (rednote_position_y), d0 ; red note y position in d0 add.w (tempo), d0 ; add the tempo cmp.w #(note_plane_border_offset-note_bounds_bottom), d0 ; does the player miss the note entirely blt @RedNoteNotWithinBounds ; branch if the player hasn't move.w #note_start_position_y, d0 ; otherwise the player has so move the note back to the top @RedNoteNotWithinBounds: move.w d0, (rednote_position_y) ; set the red note's position normally ; yellow note movement code move.w (yellownote_position_y), d0 ; yellow note y position in d0 add.w (tempo), d0 ; add the tempo cmp.w #(note_plane_border_offset-note_bounds_bottom), d0 ; does the player miss the note entirely blt @YellowNoteNotWithinBounds ; branch if the player hasn't move.w #note_start_position_y, d0 ; otherwise the player has so move the note back to the top @YellowNoteNotWithinBounds: move.w d0, (yellownote_position_y) ; set the yellow note's position normally To this: Code: ; ************************************ ; initialize everything ; ************************************ move.b #1, (tempo) ; initialize tempo move.w #note_start_position_y, (greennote_position_y) ; Set green note's y position move.w #note_start_position_y, (rednote_position_y) ; Set red note's y position move.w #note_start_position_y, (yellownote_position_y) ; Set yellow note's y position move.w #rockindicator_start_position_x, (rockindicator_position_x) ; Set rock indicator's x position ; ****************************************************************** ; Main game loop ; ****************************************************************** GameLoop: ; green note movement code move.w (greennote_position_y), d0 ; green note y position in d0 add.b (tempo), d0 ; add the tempo cmp.w #(note_plane_border_offset-note_bounds_bottom), d0 ; does the player miss the note entirely blt @GreenNoteNotWithinBounds ; branch if the player hasn't move.w #note_start_position_y, d0 ; otherwise the player has so move the note back to the top @GreenNoteNotWithinBounds: move.w d0, (greennote_position_y) ; set the green note's position normally ; red note movement code move.w (rednote_position_y), d0 ; red note y position in d0 add.b (tempo), d0 ; add the tempo cmp.w #(note_plane_border_offset-note_bounds_bottom), d0 ; does the player miss the note entirely blt @RedNoteNotWithinBounds ; branch if the player hasn't move.w #note_start_position_y, d0 ; otherwise the player has so move the note back to the top @RedNoteNotWithinBounds: move.w d0, (rednote_position_y) ; set the red note's position normally ; yellow note movement code move.w (yellownote_position_y), d0 ; yellow note y position in d0 add.b (tempo), d0 ; add the tempo cmp.w #(note_plane_border_offset-note_bounds_bottom), d0 ; does the player miss the note entirely blt @YellowNoteNotWithinBounds ; branch if the player hasn't move.w #note_start_position_y, d0 ; otherwise the player has so move the note back to the top @YellowNoteNotWithinBounds: move.w d0, (yellownote_position_y) ; set the yellow note's position normally Causes the notes to gain super speed for some reason. Changing just the initiation code stops it from moving. I'm very new to 68k assembly so i'm gonna chalk it up to a newbie mistake. Any assistance in this matter would be greatly appreciated. Sincerely, Scorpion Illuminati
Using add.b on a word sized register is only affecting the lower 8 bits. There is probably a reason the original code is using word sized parameters?
