diff --git a/avr.instr.tex b/avr.instr.tex
index 88abc74..f563366 100644
--- a/avr.instr.tex
+++ b/avr.instr.tex
@@ -5,10 +5,14 @@
 \def\avr@error#1{%
   \avr@dump%
   \errmessage{\the\avr@pc: #1}\bye%
-
 }
 
 
+\newcount\avr@instr@executed
+\def\avr@instr@init{%
+  \avr@instr@executed=0%
+}
+
 % Execution Engine
 \def\avr@instr@step{%
   \avr@code@get{\avr@instr@current}%
@@ -19,8 +23,7 @@
   %\avr@debug{\avr@instr@current}%
   % Dispatch Instruction by prefix
   \expandafter\avr@instr@dispatch\avr@instr@current\@nnil%
-  \relax%
-
+  \advance\avr@instr@executed by 1\relax%
 }
 
 \def\avr@singlestep{%
@@ -367,10 +370,10 @@
 \csdef{avr@instr@INCDEC@helper}#1#2{%
   \avr@reg@get{#1}{\avr@Rd}%
   \avr@debug{INCDEC #1(=\avr@Rd) +(#2)}%
-  \avr@bin@tocount{\avr@Rd}{\avr@count@tmpa}%
-  \advance \avr@count@tmpa by #2\relax%
-  \avr@count@modulo@byte{\avr@count@tmpa}%
-  \avr@count@tobin@b{\avr@count@tmpa}{\avr@Rx}%
+  \avr@bin@tocount{\avr@Rd}{\avr@accA}%
+  \advance \avr@accA by #2\relax%
+  \avr@count@modulo@byte{\avr@accA}%
+  \avr@count@tobin@b{\avr@accA}{\avr@Rx}%
   \ifdefstring{\avr@Rx}{01111111}{%
     \avr@flag@set V 1%
   }{%
@@ -630,7 +633,7 @@
   \avr@reg@get{\csuse{avr@r24}}{\@@A}%
   \avr@reg@get{\csuse{avr@r25}}{\@@B}%
   \avr@reg@get{\csuse{avr@r26}}{\@@C}%
-  \avr@debug{ICALL \the\avr@count@tmpa {r24:\@@A} {r25:\@@B} {r26:\@@C}}%
+  \avr@debug{RCALL \the\avr@count@tmpa {r24:\@@A} {r25:\@@B} {r26:\@@C}}%
   \avr@CALL@helper{\@@pc}%
   \avr@pc@add{\avr@count@tmpa}%
 }
@@ -651,12 +654,12 @@
 \def\avr@instr@IJMP#1{\avr@code@set{1001010000001001}{#1}}
 \csdef{avr@instr@1001010000001001}\@nnil{
   \avr@count@tobin@w{\the\avr@pc}{\@@pc}%
-  \avr@regw@get{Z}{\@@addr}
+  \avr@regw@get{\csuse{avr@Z}}{\@@addr}
   \avr@bin@tocount{\@@addr}{\avr@addr}%
-  \avr@reg@get{\csuse{avr@r24}}{\@@A}%
-  \avr@reg@get{\csuse{avr@r25}}{\@@B}%
-  \avr@reg@get{\csuse{avr@r26}}{\@@C}%
-  \avr@debug{IJMP \the\avr@addr {r24:\@@A} {r25:\@@B} {r26:\@@C}}%
+  \avr@reg@get{\csuse{avr@r24}}{\@@a}%
+  \avr@reg@get{\csuse{avr@r25}}{\@@b}%
+  \avr@reg@get{\csuse{avr@r26}}{\@@c}%
+  \avr@debug{IJMP \the\avr@addr {r24:\@@a} {r25:\@@b} {r26:\@@c}}%
   \avr@pc=\avr@addr
 }
 
@@ -1023,7 +1026,7 @@
 }
 
 \csdef{avr@instr@1001010110011000}\@nnil{%
-  \avr@debug{BREAK}%
+  \avr@debug{BREAK: (\the\avr@instr@executed) instructions}%
   \avr@instr@steps=0\relax%
   \avr@pc@inc%
 }
@@ -1276,7 +1279,7 @@
 \def\avr@instr@LSR#1#2{\avr@code@set{1001010#20110}{#1}}
 \csdef{avr@instr@1001010:0110}#1\@nnil{%
   \avr@reg@get{#1}{\avr@Rr}%
-  \avr@debug{LSL: #1(=\avr@Rr)}%
+  \avr@debug{LSR #1(=\avr@Rr)}%
   \avr@bin@shiftright{\avr@Rr}{1}{\avr@Rx}{\@@carry}%
   \avr@bin@msb@get{\avr@Rx}{\@@N}%
   \avr@flag@set C \@@carry%
diff --git a/avr.io.tex b/avr.io.tex
index e00d958..0ca6977 100644
--- a/avr.io.tex
+++ b/avr.io.tex
@@ -22,6 +22,22 @@
   \avr@pc@inc%
 }
 
+% OUT
+\def\avr@instr@IN#1#2#3{% A, R
+  \def\@@A{#2}
+   \avr@bin@msb@del{\@@A}{\@@A}{\@@a}%
+   \avr@bin@msb@del{\@@A}{\@@A}{\@@b}%
+   \avr@code@set{10110\@@a\@@b#3\@@A}{#1}%
+}
+
+\csdef{avr@instr@10110}#1#2#3#4#5#6#7#8\@nnil{%
+  \avr@debug{IN #1#2#8 -> #3#4#5#6#7}%
+  \edef\@@IOA{#1#2#8}%
+  \avr@io@get{\@@IOA}{\avr@Rr}%
+  \avr@reg@set{\avr@Rr}{#3#4#5#6#7}%
+  \avr@pc@inc%
+}
+
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % IO Handlers
@@ -36,6 +52,7 @@
 }
 % #1=Addr, #2=\result
 \def\avr@io@get#1#2{%
+  \avr@debug{  IO R #1}%
   \ifcsdef{avr@io@#1@get}{%
     \csuse{avr@io@#1@get}{#2}%
   }{%
@@ -48,21 +65,25 @@
 }
 
 \def\avr@io@get@default#1#2{%
-  \avr@error{IO Port #1 is not defined (IN)}%
+  \avr@error{IO Port #1 is not defined (IN -> #2)}%
 }
 
 \csdef{avr@io@111111@set}#1{%
   \avr@debug{  SREG=#1}%
   \avr@sreg@set{#1}%
 }
+\csdef{avr@io@111111@get}#1{\avr@sreg@get{#1}}
 
+% Stackpointer IO Ports
 \csdef{avr@io@111110@set}#1{\avr@stack@SPH@set{#1}}
 \csdef{avr@io@111101@set}#1{\avr@stack@SPL@set{#1}}
+\csdef{avr@io@111110@get}#1{\avr@stack@SPH@get{#1}}
+\csdef{avr@io@111101@get}#1{\avr@stack@SPL@get{#1}}
 
 \csdef{avr@io@001100@set}#1{%
   \avr@bin@tocount{#1}{\avr@count@tmpa}%
   \avr@ascii{\the\avr@count@tmpa}{\@@char}%
-  \avr@debug{UDR: #1=\the\avr@count@tmpa}%
+  \avr@debug{UDR: \the\avr@count@tmpa}%
   \xdef\avr@UDR{\avr@UDR \@@char}%
 }
 
diff --git a/avr.memory.tex b/avr.memory.tex
index 5451a15..0fda7a5 100644
--- a/avr.memory.tex
+++ b/avr.memory.tex
@@ -8,6 +8,8 @@
   \avr@stack@init%
   \avr@mem@init{1024}%
   \avr@io@init%
+  \avr@instr@init%
+  \avr@debug{Initialized AVR}%
 }
 
 \newcount\avr@accA
diff --git a/avr.numbers.tex b/avr.numbers.tex
index 66f135a..ef8c572 100644
--- a/avr.numbers.tex
+++ b/avr.numbers.tex
@@ -266,10 +266,10 @@
 % \avr@count@tobin@b uint8_t count|integer, \result -> \result = bin(arg)
 \def\avr@count@tobin@b#1#2{%
   \ifnum #1 > 255 %
-     \avr@error{#1 to large value}%
+     \avr@error{#1 to large value (\the#1)}%
   \fi%
   \ifnum #1 < 0 %
-     \avr@error{#1 to small value}%
+     \avr@error{#1 to small value (\the#1)}%
   \fi%
   \avr@count@tmpa=#1%
   \ifcsdef{avr@bin@\the\avr@count@tmpa}{}{%
@@ -371,9 +371,13 @@
 \def\avr@count@modulo@byte#1{%
   \avr@count@tmpa=#1\relax%
   \avr@count@tmpb=#1\relax%
+
   \divide \avr@count@tmpa by 256\relax%
   \multiply \avr@count@tmpa by 256\relax%
   \advance \avr@count@tmpb by -\avr@count@tmpa\relax%
+  \ifnum \avr@count@tmpb < 0%
+    \advance\avr@count@tmpb by 256%
+  \fi%
   #1 = \avr@count@tmpb\relax%
 }
 
diff --git a/tests/float.c b/tests/float.c
new file mode 100644
index 0000000..aebeb5a
--- /dev/null
+++ b/tests/float.c
@@ -0,0 +1,47 @@
+#include <avr/io.h>
+#include <stdio.h>
+
+static int uart_putchar(char c, FILE *stream);
+static FILE mystdout = FDEV_SETUP_STREAM(uart_putchar, NULL,
+                                         _FDEV_SETUP_WRITE);
+static int
+uart_putchar(char c, FILE *stream)
+{
+    UDR = c;
+    return 0;
+}
+
+volatile uint16_t xxx = 65;
+
+int
+main(void)
+{
+    stdout = &mystdout;
+    printf("Hello, world!");
+
+    asm volatile("break;");
+
+
+    volatile float foo = 0.23;
+    printf("%.2f", foo);
+
+    asm volatile("break;");
+
+
+    return 0;
+}
+
+
+/**
+   check-name: Print to Stdout and Float
+   check-start:
+
+   \avr@instr@stepn{100000}
+   \avr@test@UDR{Hello, world!}
+   \xdef\avr@UDR{}
+
+   \avr@instr@stepn{100000}
+   \avr@test@UDR{0.23}
+   \def\avr@UDR{}
+   check-end:
+**/
diff --git a/tests/mul.c b/tests/mul.c
index 7fa25c2..b151383 100644
--- a/tests/mul.c
+++ b/tests/mul.c
@@ -13,6 +13,13 @@ int main() {
 
   foo[4] = foo[1] % foo[0];
 
+  volatile uint16_t x = 1000;
+  volatile uint16_t y = 55;
+
+  foo[5] = x * y;
+
+  itoa(165, &foo[6], 10);
+
   asm volatile ("break");
 }
 
@@ -28,5 +35,11 @@ int main() {
   \avr@test@MEM{99}{00000001} % 1
   \avr@test@MEM{100}{00010011} % 19
 
+  \avr@test@MEM{101}{11011000} % 216
+
+  \avr@test@MEM{102}{00110001} % '1'
+  \avr@test@MEM{103}{00110110} % '6'
+  \avr@test@MEM{104}{00110101} % '5'
+
   check-end:
 */
diff --git a/tests/printf.c b/tests/printf.c
new file mode 100644
index 0000000..fc255ba
--- /dev/null
+++ b/tests/printf.c
@@ -0,0 +1,36 @@
+#include <avr/io.h>
+#include <stdio.h>
+
+volatile char buffer[30];
+
+volatile uint16_t xxx = 165;
+
+int
+main(void)
+{
+    asm volatile("break;");
+
+    // sprintf(buffer, "%d", xxx);
+    __ultoa_invert(xxx, buffer, 10);
+
+    asm volatile("break;");
+
+
+    return 0;
+}
+
+
+/**
+   check-name: Print to Stdout
+   check-start:
+
+   \avr@instr@stepn{100000}
+   \avr@instr@executed=0
+   \avr@instr@stepn{100000}
+
+   \avr@test@MEM{96}{00110001} % '1'
+   \avr@test@MEM{97}{00110110} % '6'
+   \avr@test@MEM{98}{00110101} % '5'   
+
+   check-end:
+**/
diff --git a/tests/test-suite b/tests/test-suite
index 1544b0c..325c532 100755
--- a/tests/test-suite
+++ b/tests/test-suite
@@ -93,10 +93,10 @@ do_test()
 	fi
 	test_name=$last_result
 
-	echo "TEST    $test_name ($file)"
+	echo -n "TEST    $test_name ($file)"
 
     cp HEADER "$file".tex
-    echo "\avrloadc{$file}" >> "$file".tex
+    echo "\avrloadc[-lm -Os -mmcu=atmega8]{$file}" >> "$file".tex
 
 	awk '/check-start/,/check-end/ {print}' $file \
 		| egrep -v 'check-(start|end)' >> "$file".tex
@@ -109,6 +109,7 @@ do_test()
     rm -f *.log *.aux *.pdf
 
 	if [ "$actual_exit_value" -ne 0 ]; then
+        echo
 		error "   Actual exit value does not match the expected one."
 		error "   expected 0, got $actual_exit_value"
         if [ x"$V" = x"1" ]; then
@@ -117,6 +118,9 @@ do_test()
             tail -n 10 $file.output | sed 's/^/   /'
         fi
 		test_failed=1
+    else
+        get_value BREAK "$file".output
+        echo " ($last_result)"
 	fi
 
 	if [ "$test_failed" -eq "1" ]; then