From f2e46f0fdf5d54b7e5de8a1be8dd95925c606b92 Mon Sep 17 00:00:00 2001
From: Marco van den Heuvel <blackystardust68@yahoo.com>
Date: Wed, 25 Apr 2018 12:53:29 -0700
Subject: [PATCH 1/3] Added C64 Chameleon accelerator code and documentation.

---
 asminc/accelerator.inc                    |  15 +++-
 doc/c64.sgml                              |   3 +
 doc/funcref.sgml                          |  67 +++++++++++++++
 include/accelerator.h                     |  52 +++++++++++
 libsrc/c64/acc_chameleon_speed.s          | 100 ++++++++++++++++++++++
 libsrc/c64/acc_detect_chameleon.s         |  39 +++++++++
 testcode/lib/accelerator/Makefile         |   5 +-
 testcode/lib/accelerator/chameleon-test.c |   8 ++
 8 files changed, 287 insertions(+), 2 deletions(-)
 create mode 100755 libsrc/c64/acc_chameleon_speed.s
 create mode 100755 libsrc/c64/acc_detect_chameleon.s
 create mode 100755 testcode/lib/accelerator/chameleon-test.c

diff --git a/asminc/accelerator.inc b/asminc/accelerator.inc
index 86d27b3f2..0c687b2ad 100644
--- a/asminc/accelerator.inc
+++ b/asminc/accelerator.inc
@@ -43,7 +43,20 @@ C64DTV_Fast = $03
 
 
 ; ---------------------------------------------------------------------------
-; C128 in C64 mode
+; C128 native and C128 in C64 mode
 
 C128_VICIIE_CLK := $D030
 
+
+; ---------------------------------------------------------------------------
+; C64 Chameleon cartridge
+
+CHAMELEON_CFGTUR := $D0F3
+CHAMELEON_CFGENA := $D0FE
+
+CHAMELEON_ENABLE_REGS  = $2A
+CHAMELEON_DISABLE_REGS = $FF
+
+CHAMELEON_CFGTUR_LIMIT_1MHZ = %00001100
+CHAMELEON_CFGTUR_LIMIT_NONE = %10000000
+
diff --git a/doc/c64.sgml b/doc/c64.sgml
index c2c9551b4..c037b1e0e 100644
--- a/doc/c64.sgml
+++ b/doc/c64.sgml
@@ -177,12 +177,15 @@ url="funcref.html" name="function reference"> for declaration and usage.
 <itemize>
 <item>detect_c128
 <item>detect_c64dtv
+<item>detect_chameleon
 <item>detect_scpu
 <item>get_c128_speed
 <item>get_c64dtv_speed
+<item>get_chameleon_speed
 <item>get_scpu_speed
 <item>set_c128_speed
 <item>set_c64dtv_speed
+<item>set_chameleon_speed
 <item>set_scpu_speed
 </itemize>
 
diff --git a/doc/funcref.sgml b/doc/funcref.sgml
index 55701cf55..09ee27e4a 100644
--- a/doc/funcref.sgml
+++ b/doc/funcref.sgml
@@ -70,12 +70,15 @@ function.
 <itemize>
 <item><ref id="detect_c128" name="detect_c128">
 <item><ref id="detect_c64dtv" name="detect_c64dtv">
+<item><ref id="detect_chameleon" name="detect_chameleon">
 <item><ref id="detect_scpu" name="detect_scpu">
 <item><ref id="get_c128_speed" name="get_c128_speed">
 <item><ref id="get_c64dtv_speed" name="get_c64dtv_speed">
+<item><ref id="get_chameleon_speed" name="get_chameleon_speed">
 <item><ref id="get_scpu_speed" name="get_scpu_speed">
 <item><ref id="set_c128_speed" name="set_c128_speed">
 <item><ref id="set_c64dtv_speed" name="set_c64dtv_speed">
+<item><ref id="set_chameleon_speed" name="set_chameleon_speed">
 <item><ref id="set_scpu_speed" name="set_scpu_speed">
 </itemize>
 
@@ -2966,6 +2969,26 @@ used in presence of a prototype.
 </quote>
 
 
+<sect1>detect_chameleon<label id="detect_chameleon"><p>
+
+<quote>
+<descrip>
+<tag/Function/Check for the presence of the C64 Chameleon cartridge.
+<tag/Header/<tt/<ref id="accelerator.h" name="accelerator.h">/
+<tag/Declaration/<tt/unsigned char detect_chameleon (void);/
+<tag/Description/The function returns a 1 if a C64 Chameleon cartridge has been detected.
+<tag/Notes/<itemize>
+<item>The function is specific to the C64.
+</itemize>
+<tag/Availability/cc65 (not all platforms)
+<tag/See also/
+<ref id="get_chameleon_speed" name="get_chameleon_speed">,
+<ref id="set_chameleon_speed" name="set_chameleon_speed">,
+<tag/Example/None.
+</descrip>
+</quote>
+
+
 <sect1>detect_scpu<label id="detect_scpu"><p>
 
 <quote>
@@ -3569,6 +3592,28 @@ header files define constants that can be used to check the return code.
 </quote>
 
 
+<sect1>get_chameleon_speed<label id="get_chameleon_speed"><p>
+
+<quote>
+<descrip>
+<tag/Function/Get the current speed of the C64 Chameleon cartridge.
+<tag/Header/<tt/<ref id="accelerator.h" name="accelerator.h">/
+<tag/Declaration/<tt/unsigned char get_chameleon_speed (void);/
+<tag/Description/The function returns the current speed of the C64 Chameleon cartridge.
+<tag/Notes/<itemize>
+<item>The function is specific to the C64.
+<item>The function does not check for the presence of the C64 Chameleon cartridge.
+<item>See the accelerator.h header for the speed definitions.
+</itemize>
+<tag/Availability/cc65 (not all platforms)
+<tag/See also/
+<ref id="detect_chameleon" name="detect_chameleon">,
+<ref id="set_chameleon_speed" name="set_chameleon_speed">,
+<tag/Example/None.
+</descrip>
+</quote>
+
+
 <sect1>get_scpu_speed<label id="get_scpu_speed"><p>
 
 <quote>
@@ -6186,6 +6231,28 @@ clean-up when exitting the program.
 </quote>
 
 
+<sect1>set_chameleon_speed<label id="set_chameleon_speed"><p>
+
+<quote>
+<descrip>
+<tag/Function/Set the current speed of the C64 Chameleon cartridge.
+<tag/Header/<tt/<ref id="accelerator.h" name="accelerator.h">/
+<tag/Declaration/<tt/unsigned char __fastcall__ set_chameleon_speed (unsigned char speed);/
+<tag/Description/The function returns the speed after trying to set the speed of the C64 Chameleon cartridge.
+<tag/Notes/<itemize>
+<item>The function is specific to the C64.
+<item>The function does not check for the presence of the C64 Chameleon cartridge.
+<item>See the accelerator.h header for the speed definitions.
+</itemize>
+<tag/Availability/cc65 (not all platforms)
+<tag/See also/
+<ref id="detect_chameleon" name="detect_chameleon">,
+<ref id="get_chameleon_speed" name="get_chameleon_speed">,
+<tag/Example/None.
+</descrip>
+</quote>
+
+
 <sect1>set_scpu_speed<label id="set_scpu_speed"><p>
 
 <quote>
diff --git a/include/accelerator.h b/include/accelerator.h
index 0fa202bc6..5797cb36c 100644
--- a/include/accelerator.h
+++ b/include/accelerator.h
@@ -174,6 +174,58 @@ extern unsigned char detect_c128 (void);
  * 0x01  : C128 CPU is the current CPU
  */
 
+
+/* C64 Chameleon cartridge */
+
+extern unsigned char __fastcall__ set_chameleon_speed (unsigned char speed);
+
+/* Set the speed of the C64 Chameleon cartridge, the following inputs
+ * are accepted: 
+ * SPEED_SLOW : 1 Mhz mode
+ * SPEED_1X   : 1 Mhz mode
+ * SPEED_2X   : 2 Mhz mode
+ * SPEED_3X   : 3 Mhz mode
+ * SPEED_4X   : 4 Mhz mode
+ * SPEED_5X   : 5 Mhz mode
+ * SPEED_6X   : 6 Mhz mode
+ * SPEED_FAST : Maximum speed mode
+ *
+ * Note that any value higher or equal to SPEED_7X will switch to maximum
+ * speed mode.
+ *
+ * This function will return the actual speed the CPU is at after trying
+ * to set the requested speed, to my knowledge the switching should not fail.
+ *
+ * This function does not check for the presence of the C64 Chameleon cartridge,
+ * make sure you use 'detect_chameleon();' before using.
+ */
+
+extern unsigned char get_chameleon_speed (void);
+
+;/* Get the speed of the C64 Chameleon cartridge.
+; *
+; * Possible return values:
+; * SPEED_SLOW  : Slow mode
+; * SPEED_2X    : 2Mhz mode
+; * SPEED_3X    : 3Mhz mode
+; * SPEED_4X    : 4Mhz mode
+; * SPEED_5X    : 5Mhz mode
+; * SPEED_6X    : 6Mhz mode
+; * SPEED_FAST  : Maximum speed mode
+; *
+; * This function does not check for the presence of the C64 Chameleon cartridge,
+; * make sure you use 'detect_chameleon();' before using.
+; */
+
+extern unsigned char detect_chameleon (void);
+
+/* Check for the presence of the C64 Chameleon cartridge.
+ *
+ * Possible return values:
+ * 0x00  : C64 Chameleon cartridge not present
+ * 0x01  : C64 Chameleon cartridge present
+ */
+
 /* End of accelerator.h */
 #endif
 
diff --git a/libsrc/c64/acc_chameleon_speed.s b/libsrc/c64/acc_chameleon_speed.s
new file mode 100755
index 000000000..0e3e1320f
--- /dev/null
+++ b/libsrc/c64/acc_chameleon_speed.s
@@ -0,0 +1,100 @@
+;
+; Marco van den Heuvel, 2018-04-25
+;
+
+; extern unsigned char __fastcall__ set_chameleon_speed (unsigned char speed);
+;
+;/* Set the speed of the Chameleon cartridge, the following inputs
+; * are accepted: 
+; * SPEED_SLOW : 1 Mhz mode
+; * SPEED_1X   : 1 Mhz mode
+; * SPEED_2X   : 2 Mhz mode
+; * SPEED_3X   : 3 Mhz mode
+; * SPEED_4X   : 4 Mhz mode
+; * SPEED_5X   : 5 Mhz mode
+; * SPEED_6X   : 6 Mhz mode
+; * SPEED_FAST : Maximum speed mode
+; *
+; * Note that any value higher or equal to SPEED_7X will switch to maximum
+; * speed mode.
+; *
+; * This function will return the actual speed the CPU is at after trying
+; * to set the requested speed, to my knowledge the switching should not fail.
+; *
+; * This function does not check for the presence of the Chameleon cartridge,
+; * make sure you use 'detect_chameleon();' before using.
+; */
+
+; extern unsigned char get_chameleon_speed (void);
+;
+;/* Get the speed of the Chameleon cartridge.
+; *
+; * Possible return values:
+; * SPEED_SLOW  : Slow mode
+; * SPEED_2X    : 2Mhz mode
+; * SPEED_3X    : 3Mhz mode
+; * SPEED_4X    : 4Mhz mode
+; * SPEED_5X    : 5Mhz mode
+; * SPEED_6X    : 6Mhz mode
+; * SPEED_FAST  : Maximum speed mode
+; *
+; * This function does not check for the presence of the Chameleon cartridge,
+; * make sure you use 'detect_chameleon();' before using.
+; */
+
+        .export         _set_chameleon_speed
+        .export         _get_chameleon_speed
+
+        .include        "accelerator.inc"
+
+_set_chameleon_speed:
+        cmp     #SPEED_7X
+        bcs     maximum_speed
+        cmp     #SPEED_1X
+        beq     low_speed
+        ora     #$80
+set_speed:
+        jsr     activate_regs
+        sta     CHAMELEON_CFGTUR
+        jmp     return_speed
+
+low_speed:
+        lda     #CHAMELEON_CFGTUR_LIMIT_1MHZ
+        bne     set_speed
+
+maximum_speed:
+        lda     #CHAMELEON_CFGTUR_LIMIT_NONE
+        bne     set_speed
+
+_get_chameleon_speed:
+        jsr     activate_regs
+return_speed:
+        ldx     #$00
+        lda     CHAMELEON_CFGTUR
+        tay
+        and     #%10000000
+        beq     return_value
+        tya
+        and     #%00001000
+        bne     is_slow_mode
+        tya
+        and     #%00000111
+        beq     is_max_mode
+return_value:
+        ldy     #CHAMELEON_DISABLE_REGS
+        sty     CHAMELEON_CFGENA
+        rts
+
+is_slow_mode:
+        txa
+        bne     return_value
+
+is_max_mode:
+        lda     #SPEED_FAST
+        bne     return_value
+
+activate_regs:
+        ldy     #CHAMELEON_ENABLE_REGS
+        sty     CHAMELEON_CFGENA
+        rts
+
diff --git a/libsrc/c64/acc_detect_chameleon.s b/libsrc/c64/acc_detect_chameleon.s
new file mode 100755
index 000000000..4b90c6ea9
--- /dev/null
+++ b/libsrc/c64/acc_detect_chameleon.s
@@ -0,0 +1,39 @@
+;
+; Marco van den Heuvel, 2018-04-25
+;
+
+; unsigned char detect_chameleon (void);
+;
+;/* Check for the presence of the Chameleon cartridge.
+; *
+; * Possible return values:
+; * 0x00  : Chameleon cartridge not present
+; * 0x01  : Chameleon cartridge present
+; */
+
+        .export         _detect_chameleon
+
+        .include        "accelerator.inc"
+
+_detect_chameleon:
+        lda     #$00
+        tax
+
+; Make sure the CPU is a 6510
+        .byte   $1A                   ; NOP on 6510, INA on 65(S)C(E)02, 4510 and 65816
+        bne     not_found
+
+        ldy     CHAMELEON_CFGENA
+        lda     #CHAMELEON_ENABLE_REGS
+        sta     CHAMELEON_CFGENA
+        lda     CHAMELEON_CFGENA
+        sty     CHAMELEON_CFGENA
+        cmp     #$FF
+        beq     not_found
+found:
+        lda     #$01
+        .byte   $2C
+not_found:
+        lda     #$00
+        rts
+
diff --git a/testcode/lib/accelerator/Makefile b/testcode/lib/accelerator/Makefile
index 121ad57b8..e9bd61881 100644
--- a/testcode/lib/accelerator/Makefile
+++ b/testcode/lib/accelerator/Makefile
@@ -1,7 +1,7 @@
 CL ?= cl65
 
 all:	c64-scpu-test.prg c128-scpu-test.prg c64dtv-test.prg \
-	c64-c128-test.prg c128-test.prg
+	c64-c128-test.prg c128-test.prg chameleon-test.prg
 
 c64-scpu-test.prg: c64-c128-scpu-test.c
 	$(CL) -t c64 c64-c128-scpu-test.c -o c64-scpu-test.prg
@@ -17,3 +17,6 @@ c64-c128-test.prg: c64-c128-test.c
 
 c128-test.prg: c64-c128-test.c
 	$(CL) -t c128 c64-c128-test.c -o c128-test.prg
+
+chameleon-test.prg: chameleon-test.c
+	$(CL) -t c64 chameleon-test.c -o chameleon-test.prg
diff --git a/testcode/lib/accelerator/chameleon-test.c b/testcode/lib/accelerator/chameleon-test.c
new file mode 100755
index 000000000..ffc1539b5
--- /dev/null
+++ b/testcode/lib/accelerator/chameleon-test.c
@@ -0,0 +1,8 @@
+/* C64 Chameleon accelerator test code. */
+
+#define ACC_DETECT      detect_chameleon
+#define ACC_GET_SPEED   get_chameleon_speed
+#define ACC_SET_SPEED   set_chameleon_speed
+#define ACC_NAME        "Chameleon cartridge"
+
+#include "turbo-test.c"

From 14280151583c4ddf5cad6ecb794db4d1b651a6bb Mon Sep 17 00:00:00 2001
From: Marco van den Heuvel <blackystardust68@yahoo.com>
Date: Thu, 26 Apr 2018 09:18:54 -0700
Subject: [PATCH 2/3] Optimized the code a bit as suggested by Greg.

---
 libsrc/c64/acc_detect_chameleon.s | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libsrc/c64/acc_detect_chameleon.s b/libsrc/c64/acc_detect_chameleon.s
index 4b90c6ea9..a16a264e7 100755
--- a/libsrc/c64/acc_detect_chameleon.s
+++ b/libsrc/c64/acc_detect_chameleon.s
@@ -32,8 +32,8 @@ _detect_chameleon:
         beq     not_found
 found:
         lda     #$01
-        .byte   $2C
+        .byte   $24
 not_found:
-        lda     #$00
+        txa
         rts
 

From 97e69952c4bccac2994a2ce923502380297258c0 Mon Sep 17 00:00:00 2001
From: Marco van den Heuvel <blackystardust68@yahoo.com>
Date: Fri, 27 Apr 2018 09:16:25 -0700
Subject: [PATCH 3/3] Removed extern keyword from function prototypes.

---
 include/accelerator.h            | 22 +++++++++++-----------
 libsrc/c128/acc_c128_speed.s     |  4 ++--
 libsrc/c128/acc_scpu_speed.s     |  4 ++--
 libsrc/c64/acc_c64dtv_speed.s    |  4 ++--
 libsrc/c64/acc_chameleon_speed.s |  4 ++--
 libsrc/c64/acc_scpu_speed.s      |  4 ++--
 6 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/include/accelerator.h b/include/accelerator.h
index 5797cb36c..d29b73467 100644
--- a/include/accelerator.h
+++ b/include/accelerator.h
@@ -77,7 +77,7 @@ extern unsigned char __fastcall__ set_scpu_speed (unsigned char speed);
  * make sure you use 'detect_scpu();' before using.
  */
 
-extern unsigned char get_scpu_speed (void);
+unsigned char get_scpu_speed (void);
 
 /* Get the speed of the SuperCPU cartridge.
  *
@@ -89,7 +89,7 @@ extern unsigned char get_scpu_speed (void);
  * make sure you use 'detect_scpu();' before using.
  */
 
-extern unsigned char detect_scpu (void);
+unsigned char detect_scpu (void);
 
 /* Check for the presence of the SuperCPU cartridge.
  *
@@ -101,7 +101,7 @@ extern unsigned char detect_scpu (void);
 
 /* C64DTV */
 
-extern unsigned char __fastcall__ set_c64dtv_speed (unsigned char speed);
+unsigned char __fastcall__ set_c64dtv_speed (unsigned char speed);
 
 /* Set the speed of the C64DTV, using SPEED_SLOW will switch to
  * slow mode, SPEED_2X or SPEED_FAST will switch to fast mode.
@@ -115,7 +115,7 @@ extern unsigned char __fastcall__ set_c64dtv_speed (unsigned char speed);
  * make sure you use 'detect_c64dtv();' before using.
  */
 
-extern unsigned char get_c64dtv_speed (void);
+unsigned char get_c64dtv_speed (void);
 
 /* Get the speed of the C64DTV.
  *
@@ -127,7 +127,7 @@ extern unsigned char get_c64dtv_speed (void);
  * make sure you use 'detect_c64dtv();' before using.
  */
 
-extern unsigned char detect_c64dtv (void);
+unsigned char detect_c64dtv (void);
 
 /* Check for the presence of the C64DTV.
  *
@@ -139,7 +139,7 @@ extern unsigned char detect_c64dtv (void);
 
 /* C128 8502 CPU */
 
-extern unsigned char __fastcall__ set_c128_speed (unsigned char speed);
+unsigned char __fastcall__ set_c128_speed (unsigned char speed);
 
 /* Set the speed of the C128 8502 CPU, using SPEED_SLOW will switch to
  * 1 Mhz (slow) mode, SPEED_2X or SPEED_FAST will switch to 2Mhz (fast) mode.
@@ -153,7 +153,7 @@ extern unsigned char __fastcall__ set_c128_speed (unsigned char speed);
  * you use 'detect_c128();' before using.
  */
 
-extern unsigned char get_c128_speed (void);
+unsigned char get_c128_speed (void);
 
 /* Get the speed of the C128 8502 CPU.
  *
@@ -165,7 +165,7 @@ extern unsigned char get_c128_speed (void);
  * you use 'detect_c128();' before using.
  */
 
-extern unsigned char detect_c128 (void);
+unsigned char detect_c128 (void);
 
 /* Check if the C128 CPU is the current CPU.
  *
@@ -177,7 +177,7 @@ extern unsigned char detect_c128 (void);
 
 /* C64 Chameleon cartridge */
 
-extern unsigned char __fastcall__ set_chameleon_speed (unsigned char speed);
+unsigned char __fastcall__ set_chameleon_speed (unsigned char speed);
 
 /* Set the speed of the C64 Chameleon cartridge, the following inputs
  * are accepted: 
@@ -200,7 +200,7 @@ extern unsigned char __fastcall__ set_chameleon_speed (unsigned char speed);
  * make sure you use 'detect_chameleon();' before using.
  */
 
-extern unsigned char get_chameleon_speed (void);
+unsigned char get_chameleon_speed (void);
 
 ;/* Get the speed of the C64 Chameleon cartridge.
 ; *
@@ -217,7 +217,7 @@ extern unsigned char get_chameleon_speed (void);
 ; * make sure you use 'detect_chameleon();' before using.
 ; */
 
-extern unsigned char detect_chameleon (void);
+unsigned char detect_chameleon (void);
 
 /* Check for the presence of the C64 Chameleon cartridge.
  *
diff --git a/libsrc/c128/acc_c128_speed.s b/libsrc/c128/acc_c128_speed.s
index c3012b2c8..3f2017de9 100755
--- a/libsrc/c128/acc_c128_speed.s
+++ b/libsrc/c128/acc_c128_speed.s
@@ -2,7 +2,7 @@
 ; Marco van den Heuvel, 2018-04-23
 ;
 
-; extern unsigned char __fastcall__ set_c128_speed (unsigned char speed);
+; unsigned char __fastcall__ set_c128_speed (unsigned char speed);
 ;
 ;/* Set the speed of the C128 8502 CPU, using SPEED_SLOW will switch to
 ; * 1 Mhz (slow) mode, SPEED_2X or SPEED_FAST will switch to 2Mhz (fast) mode.
@@ -18,7 +18,7 @@
 ; * For C128 programs no detect function call is needed.
 ; */
 
-; extern unsigned char get_c128_speed (void);
+; unsigned char get_c128_speed (void);
 ;
 ;/* Get the speed of the C128 8502 CPU.
 ; *
diff --git a/libsrc/c128/acc_scpu_speed.s b/libsrc/c128/acc_scpu_speed.s
index 4bd142bbb..9f932aecd 100755
--- a/libsrc/c128/acc_scpu_speed.s
+++ b/libsrc/c128/acc_scpu_speed.s
@@ -2,7 +2,7 @@
 ; Marco van den Heuvel, 2018-04-09
 ;
 
-; extern unsigned char __fastcall__ set_scpu_speed (unsigned char speed);
+; unsigned char __fastcall__ set_scpu_speed (unsigned char speed);
 ;
 ;/* Set the speed of the SuperCPU cartridge, using SPEED_SLOW will switch to
 ; * 1 Mhz mode, SPEED_20X or SPEED_FAST will switch to 20 Mhz mode.
@@ -19,7 +19,7 @@
 ; * make sure you use 'detect_scpu();' before using.
 ; */
 
-; extern unsigned char get_scpu_speed (void);
+; unsigned char get_scpu_speed (void);
 ;
 ;/* Get the speed of the SuperCPU cartridge.
 ; *
diff --git a/libsrc/c64/acc_c64dtv_speed.s b/libsrc/c64/acc_c64dtv_speed.s
index 6a8371a9c..d6cf8b994 100755
--- a/libsrc/c64/acc_c64dtv_speed.s
+++ b/libsrc/c64/acc_c64dtv_speed.s
@@ -2,7 +2,7 @@
 ; Marco van den Heuvel, 2018-04-14
 ;
 
-; extern unsigned char __fastcall__ set_c64dtv_speed (unsigned char speed);
+; unsigned char __fastcall__ set_c64dtv_speed (unsigned char speed);
 ;
 ;/* Set the speed of the C64DTV, using SPEED_SLOW will switch to
 ; * slow mode, SPEED_2X or SPEED_FAST will switch to fast mode.
@@ -16,7 +16,7 @@
 ; * make sure you use 'detect_c64dtv();' before using.
 ; */
 
-; extern unsigned char get_c64dtv_speed (void);
+; unsigned char get_c64dtv_speed (void);
 ;
 ;/* Get the speed of the C64DTV.
 ; *
diff --git a/libsrc/c64/acc_chameleon_speed.s b/libsrc/c64/acc_chameleon_speed.s
index 0e3e1320f..ce51b9dde 100755
--- a/libsrc/c64/acc_chameleon_speed.s
+++ b/libsrc/c64/acc_chameleon_speed.s
@@ -2,7 +2,7 @@
 ; Marco van den Heuvel, 2018-04-25
 ;
 
-; extern unsigned char __fastcall__ set_chameleon_speed (unsigned char speed);
+; unsigned char __fastcall__ set_chameleon_speed (unsigned char speed);
 ;
 ;/* Set the speed of the Chameleon cartridge, the following inputs
 ; * are accepted: 
@@ -25,7 +25,7 @@
 ; * make sure you use 'detect_chameleon();' before using.
 ; */
 
-; extern unsigned char get_chameleon_speed (void);
+; unsigned char get_chameleon_speed (void);
 ;
 ;/* Get the speed of the Chameleon cartridge.
 ; *
diff --git a/libsrc/c64/acc_scpu_speed.s b/libsrc/c64/acc_scpu_speed.s
index 4bd142bbb..9f932aecd 100644
--- a/libsrc/c64/acc_scpu_speed.s
+++ b/libsrc/c64/acc_scpu_speed.s
@@ -2,7 +2,7 @@
 ; Marco van den Heuvel, 2018-04-09
 ;
 
-; extern unsigned char __fastcall__ set_scpu_speed (unsigned char speed);
+; unsigned char __fastcall__ set_scpu_speed (unsigned char speed);
 ;
 ;/* Set the speed of the SuperCPU cartridge, using SPEED_SLOW will switch to
 ; * 1 Mhz mode, SPEED_20X or SPEED_FAST will switch to 20 Mhz mode.
@@ -19,7 +19,7 @@
 ; * make sure you use 'detect_scpu();' before using.
 ; */
 
-; extern unsigned char get_scpu_speed (void);
+; unsigned char get_scpu_speed (void);
 ;
 ;/* Get the speed of the SuperCPU cartridge.
 ; *