Squeezed bytes and cycles out of the kbhit functions for almost all platforms.

git-svn-id: svn://svn.cc65.org/cc65/trunk@4480 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/atari/kbhit.s

@@ -1,17 +1,23 @@
 ;
 ; Christian Groessler, 19-Feb-2000
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
+	.import	       	return1
 
 	.include	"atari.inc"
 
-_kbhit:
+.proc   _kbhit
-	ldx	CH		; last pressed key
+
-	inx			; 255 means "no key"
+	ldx   	CH		; last pressed key
-	bne	L1
+	inx   			; 255 means "no key"
-	jmp	return0
+	bne   	L1
-L1:	jmp	return1
+        txa                     ; X = A = 0
+        rts
+L1:	jmp   	return1
+
+.endproc
+
+

libsrc/c128/kbhit.s

@@ -1,21 +1,25 @@
 ;
 ; Ullrich von Bassewitz, 18.08.1998
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
 
 	.include	"c128.inc"
 
-_kbhit:
+
+.proc   _kbhit
+
+        ldx     #0              ; High byte of return is always zero
 	lda	KEY_COUNT	; Get number of characters
 ;	ora	FKEY_COUNT	; Or with number of chars from function keys
-	bne   	L1
+        beq     L9
-	jmp	return0
+        lda     #1
-L1:	jmp	return1
+L9:     rts
-
+
+.endproc
 
 
 
+                

libsrc/c16/kbhit.s

@@ -1,20 +1,25 @@
 ;
 ; Ullrich von Bassewitz, 06.08.1998
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
 
 	.include	"plus4.inc"
 
-_kbhit:
+
+.proc   _kbhit
+
+        ldx     #0              ; High byte of return is always zero
 	lda	KEY_COUNT	; Get number of characters
 	ora	FKEY_COUNT	; Or with number of chars from function keys
-	bne   	L1
+        beq     L9
-	jmp	return0
+        lda     #1
-L1:	jmp	return1
+L9:     rts
+
+.endproc
+
 
 
 

libsrc/c64/kbhit.s

@@ -1,20 +1,23 @@
 ;
 ; Ullrich von Bassewitz, 06.08.1998
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
 
 	.include	"c64.inc"
 
-_kbhit:
+
+.proc   _kbhit
+
+        ldx     #0              ; High byte of return is always zero
 	lda	KEY_COUNT	; Get number of characters
-	bne   	L1
+        beq     L9
-	jmp	return0
+        lda     #1
-L1:	jmp	return1
+L9:     rts
-
+
+.endproc
 
 
 

libsrc/cbm510/kbhit.s

@@ -1,23 +1,24 @@
 ;
 ; Ullrich von Bassewitz, 06.08.1998
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
         .import         keyidx: zp
 
 
-.proc	_kbhit
+.proc   _kbhit
-	lda	keyidx          ; Get number of characters
+
-	bne   	L1
+        ldx     #0              ; High byte of return is always zero
-	jmp	return0
+       	lda    	keyidx          ; Get number of characters
-L1:	jmp	return1
+        beq     L9
+        lda     #1
+L9:     rts
+
 .endproc
 
 
 
 
 
-

libsrc/cbm610/kbhit.s

@@ -1,23 +1,22 @@
 ;
 ; Ullrich von Bassewitz, 06.08.1998
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
         .import         keyidx: zp
 
 
-.proc	_kbhit
+.proc   _kbhit
-	lda	keyidx          ; Get number of characters
+
-	bne   	L1
+        ldx     #0              ; High byte of return is always zero
-	jmp	return0
+       	lda    	keyidx          ; Get number of characters
-L1:	jmp	return1
+        beq     L9
+        lda     #1
+L9:     rts
+
 .endproc
 
 
 
-
-
-

libsrc/geos/conio/kbhit.s

@@ -7,12 +7,16 @@
 ; unsigned char kbhit (void);
 
 	    .export _kbhit
-	    .import return0, return1
 
 	    .include "../inc/geossym.inc"
 
-_kbhit:
+.proc   _kbhit
-	    lda pressFlag
+
-	    bmi L1
+        ldx     #0              ; High byte of result
-	    jmp return0
+        lda     pressFlag
-L1:	    jmp return1
+        rol                     ; Bit 7 is new key flag
+        txa                     ; A = 0
+        rol
+        rts
+
+.endproc

libsrc/lynx/kbhit.s

@@ -7,7 +7,7 @@
 	.export		_kbhit
 	.export		KBEDG
 	.export		KBSTL
-	.import		return0, return1
+	.import		return1
 
 ; --------------------------------------------------------------------------
 ; The Atari Lynx has a very small keyboard - only 3 keys
@@ -49,7 +49,8 @@ _kbhit:
 	sta	KBNPR		; inverted previous ones pressed
 	stx	KBPRV
 	lda	KBEDG
-	beq @L1
+       	beq     @L1
 	jmp	return1		; Key hit
-@L1:
+
-	jmp	return0		; No new keys hit
+@L1:    tax                     ; No new keys hit
+        rts

libsrc/pet/kbhit.s

@@ -1,20 +1,22 @@
 ;
 ; Ullrich von Bassewitz, 26.11.1998
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
 
 	.include	"pet.inc"
 
-_kbhit:
+
-	lda	KEY_COUNT   	; Get number of characters
+.proc   _kbhit
-	bne   	L1
+
-	jmp	return0
+        ldx     #0              ; High byte of return is always zero
-L1:	jmp	return1
+	lda	KEY_COUNT	; Get number of characters
-
+        beq     L9
-
+        lda     #1
+L9:     rts
+
+.endproc
 
 

libsrc/plus4/kbhit.s

@@ -1,21 +1,24 @@
 ;
 ; Ullrich von Bassewitz, 06.08.1998
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
+
-	
 	.include	"plus4.inc"
 
-_kbhit:
+
+.proc   _kbhit
+
+        ldx     #0              ; High byte of return is always zero
 	lda	KEY_COUNT	; Get number of characters
 	ora	FKEY_COUNT	; Or with number of chars from function keys
-	bne   	L1
+        beq     L9
-	jmp	return0
+        lda     #1
-L1:	jmp	return1
+L9:     rts
-
+
+.endproc
 
 
 

libsrc/vic20/kbhit.s

@@ -1,20 +1,23 @@
 ;
 ; Ullrich von Bassewitz, 06.08.1998
 ;
-; int kbhit (void);
+; unsigned char kbhit (void);
 ;
 
 	.export		_kbhit
-	.import		return0, return1
 
 	.include	"vic20.inc"
 
-_kbhit:
+
+.proc   _kbhit
+
+        ldx     #0              ; High byte of return is always zero
 	lda	KEY_COUNT	; Get number of characters
-	bne   	L1
+        beq     L9
-	jmp	return0
+        lda     #1
-L1:	jmp	return1
+L9:     rts
-
+
+.endproc