Reading Controllers - Revision history

E5frog: /* Reading the four console buttons */

2020-08-06T18:58:08Z

‎Reading the four console buttons

E5frog: /* Reading the four console buttons */

2020-08-06T18:57:07Z

‎Reading the four console buttons

E5frog: /* Controller directions in the register */

2020-08-06T18:54:46Z

‎Controller directions in the register

E5frog: /* Controller directions in the register */

2020-08-06T18:48:56Z

‎Controller directions in the register

E5frog: /* Wait for controller movement */

2020-08-06T18:48:08Z

‎Wait for controller movement

E5frog: /* Reading the four console buttons */

2020-08-06T18:39:37Z

‎Reading the four console buttons

E5frog at 07:32, 5 December 2019

2019-12-05T07:32:42Z

E5frog: /* Conclusion */

2019-07-25T17:59:05Z

‎Conclusion

E5frog: /* Reading the four console buttons */

2019-07-25T17:58:35Z

‎Reading the four console buttons

E5frog: /* Store result for later use */

2012-11-21T13:18:06Z

‎Store result for later use

@@ Line 137: / Line 137: @@
 readbuts:       ins  0                    ; $00C1 - read buttons
                  com                       ; Invert port data, 1 now means pushed
-                 ni   $0f                  ; Just keep button data
+                 ni   $0F                  ; Just keep button data
                  bz   readbuts             ;
                  lr   $4, A                ; Button indata now in r4
-                 li   $ff                  ; Set r5 to $FF and decrease it
+                 li   $FF                  ; Set r5 to $FF and decrease it
                  lr   5, A                 ;
 debounce:       ds   5                    ;
                  bnz  debounce             ;
-                 br   delay                ; Also do a delay, for some reason
+                 br   delay                ; Also do a delay (for some reason)
                  ; Delay routine is located earlier in the code:
-delay:          li   $ff                 ;$008f - parameter in r5, uses r6
+delay:          li   $FF                  ;$008F - parameter in r5, uses r6
-                 lr   6, A                ;
+                 lr   6, A                 ;
-dlyloop:        ds   6                   ;
+dlyloop:        ds   6                    ;
-                 bnz  dlyloop             ;
+                 bnz  dlyloop              ;
-                 ds   5                   ; Loops another time if value is set in r5
+                 ds   5                    ; Loops another time if value is set in r5
-                 bnz  delay               ;
+                 bnz  delay                ;
-                 pop                      ;
+                 pop                       ;
 </pre>

@@ Line 136: / Line 136: @@
 <pre>
 readbuts:       ins  0                    ; $00C1 - read buttons
-                 com                       ; Inverse port data, 1 means pushed
+                 com                       ; Invert port data, 1 now means pushed
                  ni   $0f                  ; Just keep button data
                  bz   readbuts             ;

@@ Line 33: / Line 33: @@
 == Controller directions in the register ==
-After the hand controller data has been read you can invert it back since it is inverted when output from the controller buffer - we do that to get the real data back and because it might be easier to work with later on.
+After the hand controller data has been read from the port latch a 1 means inactive and 0 means active.
-The 8 bits is stored in Accumulator (A) and the bits mean this:
+It's common to want the 1 showing active signal therefore it's inverted with the com opcode as seen above.
 <pre>
@@ Line 59: / Line 62: @@
 Combinations are possible to:
 %10000010  push down + left
 There are combinations that are impossible with a normal fully functional controller since they are opposite directions:
 %11000000  push down + pull up
 The "Jet Stick" however could do this as the fire button is parallel to the push down function.
 </pre>
-After reading the controller/s you can store the result in a register (or in available RAM) for use later or check directly which direction was chosen. Let's suppose you have a game where you can move forward, backward, right or left with the right hand controller. If we store the result of the controller in register 8, this is how to do it:
+After reading the controller/s it's handy to store it in a register (or in available RAM) for use later <br>
 == Store result for later use ==

@@ Line 46: / Line 46: @@
 bit  6  pull up
 bit  7  push down
 Port-data
 %00000001  right

@@ Line 3: / Line 3: @@
 The simplest use of hand controller is to just pause and wait for a movement, this subroutine does just that, you call it with:
 <pre>
-; your program, waiting for any user input
+; Add this subroutine call to your code:
@@ Line 27: / Line 18: @@
 	outs	0					; enable input from both hand controllers
 	outs	1					; clear latch of port of right hand controller
 	ins	1					; fetch inverted data from right hand controller
-	com						; re-invert controller data (a %1 now means active)
+	com						; invert controller data (a %1 now means active)
 	bnz	wait.4.controller.input.end		; if no movement then input is 0 -> no branch
 	; check the other controller
 	ins	4					; fetch inverted data from left hand controller
-	com						; re-invert controller data (a %1 now means active)
+	com						; invert controller data (if bit is 1 it means active)
-	bnz	wait.4.controller.input.end		; if anything was %1 jump to end of subroutine
+	bz	wait.4.controller.input			; if there's no indata repeat
 wait.4.controller.input.end:
-	pop						; return from subroutine</pre>
+	pop						; return from subroutine, controller data in A
 == Controller directions in the register ==

@@ Line 135: / Line 135: @@
 == Reading the four console buttons ==
-This code reads the buttons, you can then mask this result similar to the hand controller:
+There's a routine in the Channel F firmware that can be used directly if needed.<br>
 <pre>
 	lr	A, 4				; load button result into Ackumulator again
 	ni	%00000010			; mask out button #2
@@ Line 162: / Line 186: @@
 <pre>
+-----4321
 %00000001  button 1
 %00000010  button 2
@@ Line 178: / Line 202: @@
 %00001110
 %00001111   all buttons pressed
 == Quickest controller read ==
 <pre>

← Older revision		Revision as of 07:32, 5 December 2019
Line 182:		Line 182:

	</pre>		</pre>
		+	== Quickest controller read ==
		+	<pre>
		+	readController:
		+	clr
		+	outs 0
		+	outs 1
		+	ins 1
		+	pop
		+	</pre>
		+
		+	This one only reads data for right controller as port read is faster on the CPU where right controller is hooked up.
		+	Data is not inverted, for an active movement the bit is set to 0, any masking is done in the main program if needed.
		+

	== Conclusion ==		== Conclusion ==

@@ Line 206: / Line 206: @@
 <pre>
 	ins	0
 	com

@@ Line 139: / Line 139: @@
 <pre>
 	; read buttons
 	ins	0				; get input from port 0
 	com					; invert

@@ Line 115: / Line 115: @@
-We now have one of these bitpatterns in r8:
+We now have one of these bit patterns in r8:
 %00000000	no movement
@@ Line 128: / Line 128: @@
 Nothing else is possible with your normal controller unless something is broken.
 </pre>