diff --git a/c64/,,config_generic.s b/c64/,,config_generic.s
index bfe8029d..2659f198 100644
--- a/c64/,,config_generic.s
+++ b/c64/,,config_generic.s
@@ -6,7 +6,7 @@
 //
 
 // Idea:
-// - sane defaults for the original Commodore 64 machine
+// - sane defaults for the original Commodore 64/128 machines
 // - do not enable features which are a significant compatibility risk
 
 
@@ -49,6 +49,7 @@
 
 
 // #define CONFIG_LEGACY_SCNKEY // XXX document this
+#define CONFIG_KEYBOARD_C128 // XXX document this
 // #define CONFIG_KEY_REPEAT_DEFAULT // XXX document this
 // #define CONFIG_KEY_REPEAT_ALWAYS // XXX document this
 #define CONFIG_KEY_FAST_SCAN // XXX document this
diff --git a/c64/,,config_mega65.s b/c64/,,config_mega65.s
index 8f874fb1..3fce219e 100644
--- a/c64/,,config_mega65.s
+++ b/c64/,,config_mega65.s
@@ -51,6 +51,7 @@
 
 
 #define CONFIG_LEGACY_SCNKEY // XXX document this
+// #define CONFIG_KEYBOARD_C128 // XXX document this
 // #define CONFIG_KEY_REPEAT_DEFAULT // XXX document this
 // #define CONFIG_KEY_REPEAT_ALWAYS // XXX document this
 #define CONFIG_KEY_FAST_SCAN // XXX document this
diff --git a/c64/,,config_ultimate64.s b/c64/,,config_ultimate64.s
index 9b37ebab..f1f55f9d 100644
--- a/c64/,,config_ultimate64.s
+++ b/c64/,,config_ultimate64.s
@@ -49,6 +49,7 @@
 
 
 // #define CONFIG_LEGACY_SCNKEY // XXX document this
+// #define CONFIG_KEYBOARD_C128 // XXX document this
 // #define CONFIG_KEY_REPEAT_DEFAULT // XXX document this
 // #define CONFIG_KEY_REPEAT_ALWAYS // XXX document this
 #define CONFIG_KEY_FAST_SCAN // XXX document this
diff --git a/c64/kernal/keyboard/kb_matrix_bucky.s b/c64/kernal/keyboard/kb_matrix_bucky.s
index 32150a3a..8b658609 100644
--- a/c64/kernal/keyboard/kb_matrix_bucky.s
+++ b/c64/kernal/keyboard/kb_matrix_bucky.s
@@ -16,6 +16,28 @@ kb_matrix_bucky_confmask: // values to be written to CIA1_PRA
 	.byte %10111111 // SHIFT (right)
 	.byte %01111111 // VENDOR      
 	.byte %01111111 // CTRL
+#if CONFIG_KEYBOARD_C128
+	.byte %11111111 // C128 extra keys
+	.byte %11111111
+#endif
+
+
+__kb_matrix_bucky_confmask_end:
+
+
+#if CONFIG_KEYBOARD_C128
+
+kb_matrix_bucky_confmask_c128: // values to be written to VIC_XSCAN
+
+	.byte %11111111
+	.byte %11111111
+	.byte %11111111
+	.byte %11111111
+
+	.byte %11111011 // ALT
+	.byte %11111011 // NO_SCRL
+
+#endif
 
 
 kb_matrix_bucky_testmask: // for AND with CIA1_PRB value
@@ -24,13 +46,22 @@ kb_matrix_bucky_testmask: // for AND with CIA1_PRB value
 	.byte %00010000 // SHIFT (right)
 	.byte %00100000 // VENDOR
 	.byte %00000100 // CTRL
+#if CONFIG_KEYBOARD_C128
+	.byte %10000000 // ALT
+	.byte %00000001 // NO_SCRL
+#endif
 
 
 kb_matrix_bucky_shflag: // mask to be ORed to SHFLAG to mark key status
+
 	.byte KEY_FLAG_SHIFT
 	.byte KEY_FLAG_SHIFT
 	.byte KEY_FLAG_VENDOR
 	.byte KEY_FLAG_CTRL
+#if CONFIG_KEYBOARD_C128
+	.byte KEY_FLAG_ALT
+	.byte KEY_FLAG_NO_SCRL
+#endif
 
 
 #endif // no CONFIG_LEGACY_SCNKEY
diff --git a/c64/kernal/keyboard/keyboard_disconnect.s b/c64/kernal/keyboard/keyboard_disconnect.s
index 12708fb6..37f4e973 100644
--- a/c64/kernal/keyboard/keyboard_disconnect.s
+++ b/c64/kernal/keyboard/keyboard_disconnect.s
@@ -8,5 +8,8 @@ keyboard_disconnect:
 
 	ldx #$FF
 	stx CIA1_PRA  // disconnect all the rows
+#if CONFIG_KEYBOARD_C128
+	stx VIC_XSCAN
+#endif
 
 	rts
diff --git a/c64/kernal/keyboard/scnkey.s b/c64/kernal/keyboard/scnkey.s
index c4454dd2..60a72767 100644
--- a/c64/kernal/keyboard/scnkey.s
+++ b/c64/kernal/keyboard/scnkey.s
@@ -21,7 +21,7 @@
 // - RPTFLG  - whether key repeat is allowed
 
 
-// XXX add Commodore 128 keyboard support
+// XXX finish Commodore 128 keyboard support
 // XXX add Commodore 65 keyboard support
 
 
@@ -40,14 +40,15 @@ SCNKEY:
 	lda #$00
 	sta SHFLAG
 
-	// XXX retrieve ALT and NO_SCRL status for C128/C65 keyboards
-
 	// Check for any activity
 
 #if !CONFIG_JOY2_CURSOR && CONFIG_KEY_FAST_SCAN
 
 	ldx #$00
 	stx CIA1_PRA                   // connect all the rows
+#if CONFIG_KEYBOARD_C128
+	stx VIC_XSCAN
+#endif
 	dex                            // puts $FF
 	cpx CIA1_PRB
 	beq scnkey_no_keys
@@ -56,10 +57,15 @@ SCNKEY:
 
 	// Retrieve SHIFT / VENDOR / CTRL status
 	// Use .X to detect 2 or more keys pressed (should be $FF now)
-	ldy #$03
+
+	ldy #(__kb_matrix_bucky_confmask_end - kb_matrix_bucky_confmask - 1)
 scnkey_bucky_loop:
 	lda kb_matrix_bucky_confmask, y
 	sta CIA1_PRA
+#if CONFIG_KEYBOARD_C128
+	lda kb_matrix_bucky_confmask_c128, y
+	sta VIC_XSCAN
+#endif
 	lda kb_matrix_bucky_testmask, y
 	and CIA1_PRB
 	bne !+                          // not pressed
@@ -76,8 +82,6 @@ scnkey_bucky_loop:
 
 #if CONFIG_JOY2_CURSOR
 
-	// XXX why this does not work ???
-
 	// Check for control port 2 activity
 
 	ldx #$00
@@ -97,6 +101,9 @@ scnkey_bucky_loop:
 
 	inx                            // puts $00
 	stx CIA1_PRA                   // connect all the rows
+#if CONFIG_KEYBOARD_C128
+	stx VIC_XSCAN
+#endif
 	dex                            // puts $FF
 	cpx CIA1_PRB
 	beq scnkey_no_keys
@@ -169,9 +176,13 @@ scnkey_no_keys:
 
 	// Mark no key press
 
-	lda #$40 // XXX adapt value for C128 and C65 keyboards
-	sta LSTX
+#if CONFIG_KEYBOARD_C128
+	lda #$FF                       // non-standard, but for C128 keyboard $40 is a valid position
+#else
+	lda #$40
+#endif
 
+	sta LSTX
 	rts
 
 #if CONFIG_JOY1_CURSOR
@@ -231,8 +242,6 @@ scnkey_got_key: // .Y should now contain the key offset in matrix pointed by KEY
 	//
 	// Besides - since I am the one who writes the code, I will make the values exactly how I like them :D
 
-	// XXX consider making it configurable, also make configurable RPTFLG
-
 	lda #$16
 	sta DELAY
 
@@ -244,7 +253,7 @@ scnkey_output_key:
 
 	lda NDX
 	cmp XMAX
-	bcs scnkey_early_repeat        // no space in buffer XXX set timer to trigger repeat the next time
+	bcs scnkey_early_repeat        // no space in buffer
 
 	// Reinitialize secondary counter