;============================== ; Handle Keypress ;============================== handle_keypress: ; first handle joystick lda JOYSTICK_ENABLED beq actually_handle_keypress ; only check joystick every-other frame lda FRAMEL and #$1 beq actually_handle_keypress check_button: lda PADDLE_BUTTON0 bpl button_clear lda JS_BUTTON_STATE bne js_check lda #1 sta JS_BUTTON_STATE lda #' ' jmp check_sound button_clear: lda #0 sta JS_BUTTON_STATE js_check: jsr handle_joystick js_check_left: lda value0 cmp #$20 bcs js_check_right ; if less than 32, left lda #'A' bne check_sound js_check_right: cmp #$40 bcc js_check_up lda #'D' bne check_sound js_check_up: lda value1 cmp #$20 bcs js_check_down lda #'W' bne check_sound js_check_down: cmp #$40 bcc done_joystick lda #'S' bne check_sound done_joystick: actually_handle_keypress: lda KEYPRESS bmi keypress jmp no_keypress keypress: and #$7f ; clear high bit cmp #' ' beq check_sound ; make sure not to lose space and #$df ; convert uppercase to lower case check_sound: cmp #$14 ; control-T bne check_help lda SOUND_STATUS eor #SOUND_DISABLED sta SOUND_STATUS jmp done_keypress check_help: cmp #'H' ; H (^H is same as left) bne check_joystick jsr print_help jmp done_keypress ; can't be ^J as that's the same as down check_joystick: cmp #'J' ; J bne check_left lda JOYSTICK_ENABLED eor #1 sta JOYSTICK_ENABLED jmp done_keypress check_left: cmp #'A' beq left_pressed cmp #8 ; left key bne check_right left_pressed: ldy MARS_X dey ldx MARS_Y jsr check_valid_feet bcc done_left_pressed dec MARS_X done_left_pressed: jmp done_keypress check_right: cmp #'D' beq right_pressed cmp #$15 ; right key bne check_up right_pressed: ldy MARS_X iny ldx MARS_Y jsr check_valid_feet bcc done_right_pressed inc MARS_X done_right_pressed: jmp done_keypress check_up: cmp #'W' beq up_pressed cmp #$0B ; up key bne check_down up_pressed: ldy MARS_X ldx MARS_Y dex jsr check_valid_feet bcc done_up_pressed dec MARS_Y done_up_pressed: jmp done_keypress check_down: cmp #'S' beq down_pressed cmp #$0A bne check_space down_pressed: ldy MARS_X ldx MARS_Y inx jsr check_valid_feet bcc done_up_pressed inc MARS_Y done_down_pressed: jmp done_keypress check_space: cmp #' ' bne check_return space_pressed: jsr do_action jmp done_keypress check_return: cmp #13 bne check_escape return_pressed: ;inc LEVEL_OVER jsr do_action done_return: jmp no_keypress check_escape: cmp #27 bne done_keypress jsr print_quit jmp done_keypress done_keypress: no_keypress: bit KEYRESET rts