diff options
| -rw-r--r-- | space/include/joypad.s | 44 |
1 files changed, 22 insertions, 22 deletions
diff --git a/space/include/joypad.s b/space/include/joypad.s index 8711c28..365a7a8 100644 --- a/space/include/joypad.s +++ b/space/include/joypad.s @@ -7,6 +7,28 @@ ;; the bitmask of the buttons that are pressed from each controller. ;;; +;; READ_CONTROLLER reads the input from the controller mapped into the given +;; port, and saves the state into the given `buttons` address. +;; Implementation taken from NESHacker's example of smb3-like movement. +.macro READ_CONTROLLER port, buttons + lda Joypad::m_inv_buttons + tay + lda #1 + sta port + sta Joypad::m_inv_buttons + lsr + sta port +: + lda port + lsr + rol Joypad::m_inv_buttons + bcc :- + tya + eor Joypad::m_inv_buttons + and Joypad::m_inv_buttons + sta buttons +.endmacro + .scope Joypad ;; Button masks. BUTTON_A = 1 << 7 @@ -31,28 +53,6 @@ m_buttons1 = $22 m_buttons2 = $23 - ;; READ_CONTROLLER reads the input from the controller mapped into the given - ;; port, and saves the state into the given `buttons` address. - ;; Implementation taken from NESHacker's example of smb3-like movement. - .macro READ_CONTROLLER port, buttons - lda m_inv_buttons - tay - lda #1 - sta port - sta m_inv_buttons - lsr - sta port - : - lda port - lsr - rol m_inv_buttons - bcc :- - tya - eor m_inv_buttons - and m_inv_buttons - sta buttons - .endmacro - ;; read sets the values for m_buttons1 and m_buttons2 as read from both ;; controllers. .proc read |