tweak driver to no more use IRQ

libsrc/c64/joy/c64-hitjoy.s

@@ -73,13 +73,22 @@ UNINSTALL:
         rts
 
 ; ------------------------------------------------------------------------
-; IRQ entry point. Is called from the C layer as a subroutine in the
+; COUNT: Return the total number of available joysticks in a/x.
-; interrupt. The routine MUST return carry set if the interrupt has been
+;
-; 'handled' - which means that the interrupt source is gone. Otherwise it
-; MUST return carry clear.
 
-IRQ:    ; cia 2 setup
+COUNT:  lda     #<JOY_COUNT
+        ldx     #>JOY_COUNT
+        rts
 
+; ------------------------------------------------------------------------
+; READ: Read a particular joystick passed in A.
+;
+
+readadapter:
+
+        sei
+
+        ; cia 2 setup
         ldy     #$00            ; port b direction
         sty     $dd03           ; => input
 
@@ -143,32 +152,24 @@ IRQ:    ; cia 2 setup
         sta     temp4
 
 fire:
-        ; Default Value: $40/64 on PAL
+        ; FIXME: to be really 100% correct this should restore the correct timer
-        ;                    $42/66 on NTSC
+        ;        values for the respective machine (PAL: $4025, NTSC: $4295)
+        ;        however, this should hardly be a problem in a real world program
+
         lda     #$41
         sta     $dc05
-        ; Default Value: $25/37 on PAL
-        ;                    $95/149 on NTSC
         lda     #0
         sta     $dc04
 
-        ; We do never "handle" the interrupt, we use it just as a timer.
+        cli
-        clc
         rts
 
-; ------------------------------------------------------------------------
+READ:
-; COUNT: Return the total number of available joysticks in a/x.
+        pha
-;
+        jsr readadapter
+        pla
 
-COUNT:  lda     #<JOY_COUNT
+        tax            ; Joystick number into X
-        ldx     #>JOY_COUNT
-        rts
-
-; ------------------------------------------------------------------------
-; READ: Read a particular joystick passed in A.
-;
-
-READ:   tax            ; Joystick number into X
         bne joy2
 
 ; Read joystick 1
@@ -214,4 +215,3 @@ joy4:   lda     temp4
         eor     #$1F
         ldx     #0
         rts
-