diff --git a/include/c64/memmap.h b/include/c64/memmap.h
index ec0792a..dadd0ad 100644
--- a/include/c64/memmap.h
+++ b/include/c64/memmap.h
@@ -7,6 +7,7 @@
 #define MMAP_NO_BASIC	0x36
 #define MMAP_NO_ROM		0x35
 #define MMAP_RAM		0x30
+#define MMAP_CHAR_ROM	0x31
 
 // Install an IRQ an NMI trampoline, that routes the kernal interrupts
 // through an intermediate trampoline when the kernal ROM is not paged
diff --git a/include/c64/rasterirq.c b/include/c64/rasterirq.c
index ea05db5..afc2cb1 100644
--- a/include/c64/rasterirq.c
+++ b/include/c64/rasterirq.c
@@ -89,6 +89,9 @@ ex:
 
 __asm irq1
 {	
+	lda $d019
+	bpl ex2
+
 	ldx	nextIRQ
 l1:
 	lda	rasterIRQNext, x
@@ -131,7 +134,6 @@ e2:
 	lda npos
 	sta tpos
 
-	asl $d019
 	jmp ex
 
 e1:
@@ -144,7 +146,11 @@ e1:
 	
 ex:
 	asl $d019
+	jmp $ea81
 
+ex2:
+	LDA $DC0D
+	cli
 	jmp $ea31
 }
 
@@ -268,12 +274,13 @@ void rirq_init(bool kernalIRQ)
     {
         sei
 
+#if 0 
         // disable CIA interrupts
 
         lda #$7f
         sta $dc0d
         sta $dd0d
-
+#endif
     }
 
     if (kernalIRQ)
diff --git a/include/gfx/bitmap.c b/include/gfx/bitmap.c
index 9ce5726..c82b59a 100644
--- a/include/gfx/bitmap.c
+++ b/include/gfx/bitmap.c
@@ -2,6 +2,7 @@
 #include "tinyfont.h"
 #include <stdlib.h>
 #include <c64/asm6502.h>
+#include <string.h>
 
 void bm_init(Bitmap * bm, char * data, char cw, char ch)
 {
diff --git a/include/stdio.c b/include/stdio.c
index ec3cdac..46491f9 100644
--- a/include/stdio.c
+++ b/include/stdio.c
@@ -964,9 +964,9 @@ int scanf_func(void * fparam)
 	return getchar();
 }
 
-int sscanf(const char * fmt, const char * str, ...)
+int sscanf(const char * str, const char * fmt, ...)
 {
-	return fpscanf(fmt, sscanf_func, &str, (void **)((&str) + 1));
+	return fpscanf(fmt, sscanf_func, &str, (void **)((&fmt) + 1));
 }
 
 int scanf(const char * fmt, ...)
diff --git a/include/stdio.h b/include/stdio.h
index ea5f55c..21c8167 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -18,7 +18,7 @@ int sprintf(char * str, const char * fmt, ...);
 
 int scanf(const char * fmt, ...);
 
-int sscanf(const char * fmt, const char * str, ...);
+int sscanf(const char * str, const char * fmt, ...);
 
 #pragma compile("stdio.c")
 
diff --git a/oscar64/NativeCodeGenerator.cpp b/oscar64/NativeCodeGenerator.cpp
index 5336053..f21e27a 100644
--- a/oscar64/NativeCodeGenerator.cpp
+++ b/oscar64/NativeCodeGenerator.cpp
@@ -7872,7 +7872,7 @@ bool NativeCodeBasicBlock::MergeBasicBlocks(void)
 				changed = true;
 			}
 
-			while (mTrueJump && mTrueJump->mIns.Size() == 0 && !mTrueJump->mFalseJump && !mTrueJump->mLocked && mTrueJump != this)
+			while (mTrueJump && mTrueJump->mIns.Size() == 0 && !mTrueJump->mFalseJump && !mTrueJump->mLocked && mTrueJump != this && mTrueJump->mTrueJump != mTrueJump)
 			{
 				mTrueJump->mNumEntries--;
 				mTrueJump = mTrueJump->mTrueJump;
@@ -7880,7 +7880,7 @@ bool NativeCodeBasicBlock::MergeBasicBlocks(void)
 				changed = true;
 			}
 
-			while (mFalseJump && mFalseJump->mIns.Size() == 0 && !mFalseJump->mFalseJump && !mFalseJump->mLocked && mFalseJump != this)
+			while (mFalseJump && mFalseJump->mIns.Size() == 0 && !mFalseJump->mFalseJump && !mFalseJump->mLocked && mFalseJump != this && mFalseJump->mTrueJump != mFalseJump)
 			{
 				mFalseJump->mNumEntries--;
 				mFalseJump = mFalseJump->mTrueJump;
@@ -8585,35 +8585,41 @@ bool NativeCodeBasicBlock::JoinTailCodeSequences(void)
 		{
 			if (mTrueJump->mIns.Size() > mFalseJump->mIns.Size())
 			{
-				int	i = 0, offset = mTrueJump->mIns.Size() - mFalseJump->mIns.Size();
-				while (i < mFalseJump->mIns.Size() && mFalseJump->mIns[i].IsSame(mTrueJump->mIns[i + offset]))
-					i++;
-				if (i == mFalseJump->mIns.Size())
+				if (mTrueJump->mTrueJump != mFalseJump)
 				{
-					if (mTrueJump->mTrueJump)
-						mTrueJump->mTrueJump->RemEntryBlock(mTrueJump);
-					mTrueJump->mTrueJump = mFalseJump;
-					if (mTrueJump->mTrueJump)
-						mTrueJump->mTrueJump->AddEntryBlock(mTrueJump);
-					mTrueJump->mIns.SetSize(offset);
+					int	i = 0, offset = mTrueJump->mIns.Size() - mFalseJump->mIns.Size();
+					while (i < mFalseJump->mIns.Size() && mFalseJump->mIns[i].IsSame(mTrueJump->mIns[i + offset]))
+						i++;
+					if (i == mFalseJump->mIns.Size())
+					{
+						if (mTrueJump->mTrueJump)
+							mTrueJump->mTrueJump->RemEntryBlock(mTrueJump);
+						mTrueJump->mTrueJump = mFalseJump;
+						if (mTrueJump->mTrueJump)
+							mTrueJump->mTrueJump->AddEntryBlock(mTrueJump);
+						mTrueJump->mIns.SetSize(offset);
 
-					changed = true;
+						changed = true;
+					}
 				}
 			}
 			else
 			{
-				int	i = 0, offset = mFalseJump->mIns.Size() - mTrueJump->mIns.Size();
-				while (i < mTrueJump->mIns.Size() && mTrueJump->mIns[i].IsSame(mFalseJump->mIns[i + offset]))
-					i++;
-				if (i == mTrueJump->mIns.Size())
+				if (mFalseJump->mTrueJump != mTrueJump)
 				{
-					if (mFalseJump->mTrueJump)
-						mFalseJump->mTrueJump->RemEntryBlock(mFalseJump);
-					mFalseJump->mTrueJump = mTrueJump;
-					if (mFalseJump->mTrueJump)
-						mFalseJump->mTrueJump->AddEntryBlock(mFalseJump);
-					mFalseJump->mIns.SetSize(offset);
-					changed = true;
+					int	i = 0, offset = mFalseJump->mIns.Size() - mTrueJump->mIns.Size();
+					while (i < mTrueJump->mIns.Size() && mTrueJump->mIns[i].IsSame(mFalseJump->mIns[i + offset]))
+						i++;
+					if (i == mTrueJump->mIns.Size())
+					{
+						if (mFalseJump->mTrueJump)
+							mFalseJump->mTrueJump->RemEntryBlock(mFalseJump);
+						mFalseJump->mTrueJump = mTrueJump;
+						if (mFalseJump->mTrueJump)
+							mFalseJump->mTrueJump->AddEntryBlock(mFalseJump);
+						mFalseJump->mIns.SetSize(offset);
+						changed = true;
+					}
 				}
 			}
 		}