diff --git a/README.md b/README.md
index 8fcb978..f428588 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,11 @@
 # tree-os
 
-An open source operating system, made for x86(_64)
\ No newline at end of file
+An open source operating system, made for x86(_64) to learn about how and why modern systems what exactly they do.
+
+Right now, there exists a memory allocation system, a multitasking framework supporting messages between tasks and an interrupt system to for example allow for keyboard input.
+
+A Pci system is in progress and can currently read the bus and print out the different device types that can be found.
+
+## screenshot
+
+![](tree-os.png)

diff --git a/README.md b/README.md
index 8fcb978..f428588 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,11 @@
 # tree-os
 
-An open source operating system, made for x86(_64)
\ No newline at end of file
+An open source operating system, made for x86(_64) to learn about how and why modern systems what exactly they do.
+
+Right now, there exists a memory allocation system, a multitasking framework supporting messages between tasks and an interrupt system to for example allow for keyboard input.
+
+A Pci system is in progress and can currently read the bus and print out the different device types that can be found.
+
+## screenshot
+
+![](tree-os.png)
diff --git a/src/kernel/drivers/cpu/cpuid.c b/src/kernel/drivers/cpu/cpuid.c
index 2ab6e70..436aa2e 100644
--- a/src/kernel/drivers/cpu/cpuid.c
+++ b/src/kernel/drivers/cpu/cpuid.c
@@ -4,11 +4,9 @@
 
 extern void getVendorId(char *string);
 
+char *vendorID = "xxxxxxxxxxxx";
+
 void printCPUData() {
-    char *vendorID = malloc(13 * sizeof(char));
-    vendorID[12] = 0x00;
     getVendorId(vendorID);
     printf("vendor id: %s\n", vendorID);
-    free(vendorID);
-    yields();
 }

diff --git a/README.md b/README.md
index 8fcb978..f428588 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,11 @@
 # tree-os
 
-An open source operating system, made for x86(_64)
\ No newline at end of file
+An open source operating system, made for x86(_64) to learn about how and why modern systems what exactly they do.
+
+Right now, there exists a memory allocation system, a multitasking framework supporting messages between tasks and an interrupt system to for example allow for keyboard input.
+
+A Pci system is in progress and can currently read the bus and print out the different device types that can be found.
+
+## screenshot
+
+![](tree-os.png)
diff --git a/src/kernel/drivers/cpu/cpuid.c b/src/kernel/drivers/cpu/cpuid.c
index 2ab6e70..436aa2e 100644
--- a/src/kernel/drivers/cpu/cpuid.c
+++ b/src/kernel/drivers/cpu/cpuid.c
@@ -4,11 +4,9 @@
 
 extern void getVendorId(char *string);
 
+char *vendorID = "xxxxxxxxxxxx";
+
 void printCPUData() {
-    char *vendorID = malloc(13 * sizeof(char));
-    vendorID[12] = 0x00;
     getVendorId(vendorID);
     printf("vendor id: %s\n", vendorID);
-    free(vendorID);
-    yields();
 }
diff --git a/src/kernel/drivers/pci/pci.c b/src/kernel/drivers/pci/pci.c
index c0b4336..eb49162 100644
--- a/src/kernel/drivers/pci/pci.c
+++ b/src/kernel/drivers/pci/pci.c
@@ -5,59 +5,94 @@
 #include <task.h>
 #include <util.h>
 
-uint8_t pciConfigReadByte(uint8_t bus, uint8_t device, uint8_t function,
-                          uint8_t offset) {
-    uint32_t lbus = (uint32_t)bus;
-    uint32_t lslot = (uint32_t)device;
-    uint32_t lfunc = (uint32_t)function;
+char *classNames[] = {
+    "Unclassified",
+    "Mass Storage Controller",
+    "Network controller",
+    "Display controller",
+    "Multimedia controller",
+    "Memory Controller",
+    "Bridge",
+    "Simple Communication controller",
+    "Base System Peripheral",
+    "Input Device controller",
+    "Docking station",
+    "Processor",
+    "Serial bus controller",
+    "Wireless controller",
+    "intelligent controller",
+    "sattelite communication controller",
+    "encryption controller",
+    "signal processing controller",
+    "processing accelerator",
+    "non-essential instrumentation",
+};
 
-    uint32_t address = (uint32_t)((lbus << 16) | (lslot << 11) | (lfunc << 8) |
-                                  (offset & 0xFC) | ((uint32_t)0x80000000));
+uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
+                          uint8_t offset) {
+    uint32_t address = ((bus << 16) | (device << 11) | (function << 8) |
+                        (offset & 0xFC) | 0x80000000);
+    asm("cli");
     outi(0xCF8, address);
-    ioWait();
-    return (uint8_t)(ini(0xCFC) >> ((offset & 3) * 8));
+    uint8_t result = (ini(0xCFC) >> ((offset % 4) * 8));
+    asm("sti");
+    return result;
 }
 
 uint16_t pciConfigReadWord(uint8_t bus, uint8_t device, uint8_t function,
                            uint8_t offset) {
-    return (uint16_t)pciConfigReadByte(bus, device, function, offset) << 8 |
-           (uint16_t)pciConfigReadByte(bus, device, function, offset + 1);
+    return (uint16_t)pciConfigReadByte(bus, device, function, offset) |
+           ((uint16_t)pciConfigReadByte(bus, device, function, offset + 1)
+            << 8);
 }
 
 uint8_t getHeaderType(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadByte(bus, device, function, 0x0D);
+    return pciConfigReadByte(bus, device, function, 0x0E);
 }
 
 uint16_t getVendorID(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadWord(bus, device, function, 2);
+    return pciConfigReadWord(bus, device, function, 0);
+}
+
+void checkFunction(uint8_t bus, uint8_t device, uint8_t function) {
+    uint8_t class = pciConfigReadByte(bus, device, function, 0xB);
+    uint8_t subclass = pciConfigReadByte(bus, device, function, 0xA);
+    printf("function %i:%i:%i -> %i:%i, a %s\n", bus, device, function, class,
+           subclass, classNames[class]);
 }
 
 void checkDevice(uint8_t bus, uint8_t device) {
     uint16_t vendorID = getVendorID(bus, device, 0);
-    if (vendorID == 0xFFFF)
+    if (vendorID == 0xFFFF) {
         return;
-    printf("checking device %i;%i\n", bus, device);
+    }
+    if (getHeaderType(bus, device, 0) & 0x08) {
+        // multifunction device
+        for (int function = 0; function < 8; function++) {
+            if (getVendorID(bus, device, function) != 0xFFFF) {
+                checkFunction(bus, device, function);
+            }
+        }
+    } else {
+        checkFunction(bus, device, 0);
+    }
 }
 
 void checkBus(uint8_t bus) {
-    printf("checking bus %i...\n", bus);
-    yields();
     for (uint8_t device = 0; device < 32; device++) {
         checkDevice(bus, device);
-        yields();
     }
 }
 
 void scanPCIDevices() {
     printf("scanning pci devices...\n");
-    yields();
     if (!(getHeaderType(0, 0, 0) & 0x80)) {
-        printf("discovored a single pci bus\n");
-        yields();
-        // singe bus
+        printf("discovored a single pci host controller\n");
         checkBus(0);
-        return;
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
     }
-    printf("multiple pci buses are not implemented yet!\n");
     yields();
 }

diff --git a/README.md b/README.md
index 8fcb978..f428588 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,11 @@
 # tree-os
 
-An open source operating system, made for x86(_64)
\ No newline at end of file
+An open source operating system, made for x86(_64) to learn about how and why modern systems what exactly they do.
+
+Right now, there exists a memory allocation system, a multitasking framework supporting messages between tasks and an interrupt system to for example allow for keyboard input.
+
+A Pci system is in progress and can currently read the bus and print out the different device types that can be found.
+
+## screenshot
+
+![](tree-os.png)
diff --git a/src/kernel/drivers/cpu/cpuid.c b/src/kernel/drivers/cpu/cpuid.c
index 2ab6e70..436aa2e 100644
--- a/src/kernel/drivers/cpu/cpuid.c
+++ b/src/kernel/drivers/cpu/cpuid.c
@@ -4,11 +4,9 @@
 
 extern void getVendorId(char *string);
 
+char *vendorID = "xxxxxxxxxxxx";
+
 void printCPUData() {
-    char *vendorID = malloc(13 * sizeof(char));
-    vendorID[12] = 0x00;
     getVendorId(vendorID);
     printf("vendor id: %s\n", vendorID);
-    free(vendorID);
-    yields();
 }
diff --git a/src/kernel/drivers/pci/pci.c b/src/kernel/drivers/pci/pci.c
index c0b4336..eb49162 100644
--- a/src/kernel/drivers/pci/pci.c
+++ b/src/kernel/drivers/pci/pci.c
@@ -5,59 +5,94 @@
 #include <task.h>
 #include <util.h>
 
-uint8_t pciConfigReadByte(uint8_t bus, uint8_t device, uint8_t function,
-                          uint8_t offset) {
-    uint32_t lbus = (uint32_t)bus;
-    uint32_t lslot = (uint32_t)device;
-    uint32_t lfunc = (uint32_t)function;
+char *classNames[] = {
+    "Unclassified",
+    "Mass Storage Controller",
+    "Network controller",
+    "Display controller",
+    "Multimedia controller",
+    "Memory Controller",
+    "Bridge",
+    "Simple Communication controller",
+    "Base System Peripheral",
+    "Input Device controller",
+    "Docking station",
+    "Processor",
+    "Serial bus controller",
+    "Wireless controller",
+    "intelligent controller",
+    "sattelite communication controller",
+    "encryption controller",
+    "signal processing controller",
+    "processing accelerator",
+    "non-essential instrumentation",
+};
 
-    uint32_t address = (uint32_t)((lbus << 16) | (lslot << 11) | (lfunc << 8) |
-                                  (offset & 0xFC) | ((uint32_t)0x80000000));
+uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
+                          uint8_t offset) {
+    uint32_t address = ((bus << 16) | (device << 11) | (function << 8) |
+                        (offset & 0xFC) | 0x80000000);
+    asm("cli");
     outi(0xCF8, address);
-    ioWait();
-    return (uint8_t)(ini(0xCFC) >> ((offset & 3) * 8));
+    uint8_t result = (ini(0xCFC) >> ((offset % 4) * 8));
+    asm("sti");
+    return result;
 }
 
 uint16_t pciConfigReadWord(uint8_t bus, uint8_t device, uint8_t function,
                            uint8_t offset) {
-    return (uint16_t)pciConfigReadByte(bus, device, function, offset) << 8 |
-           (uint16_t)pciConfigReadByte(bus, device, function, offset + 1);
+    return (uint16_t)pciConfigReadByte(bus, device, function, offset) |
+           ((uint16_t)pciConfigReadByte(bus, device, function, offset + 1)
+            << 8);
 }
 
 uint8_t getHeaderType(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadByte(bus, device, function, 0x0D);
+    return pciConfigReadByte(bus, device, function, 0x0E);
 }
 
 uint16_t getVendorID(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadWord(bus, device, function, 2);
+    return pciConfigReadWord(bus, device, function, 0);
+}
+
+void checkFunction(uint8_t bus, uint8_t device, uint8_t function) {
+    uint8_t class = pciConfigReadByte(bus, device, function, 0xB);
+    uint8_t subclass = pciConfigReadByte(bus, device, function, 0xA);
+    printf("function %i:%i:%i -> %i:%i, a %s\n", bus, device, function, class,
+           subclass, classNames[class]);
 }
 
 void checkDevice(uint8_t bus, uint8_t device) {
     uint16_t vendorID = getVendorID(bus, device, 0);
-    if (vendorID == 0xFFFF)
+    if (vendorID == 0xFFFF) {
         return;
-    printf("checking device %i;%i\n", bus, device);
+    }
+    if (getHeaderType(bus, device, 0) & 0x08) {
+        // multifunction device
+        for (int function = 0; function < 8; function++) {
+            if (getVendorID(bus, device, function) != 0xFFFF) {
+                checkFunction(bus, device, function);
+            }
+        }
+    } else {
+        checkFunction(bus, device, 0);
+    }
 }
 
 void checkBus(uint8_t bus) {
-    printf("checking bus %i...\n", bus);
-    yields();
     for (uint8_t device = 0; device < 32; device++) {
         checkDevice(bus, device);
-        yields();
     }
 }
 
 void scanPCIDevices() {
     printf("scanning pci devices...\n");
-    yields();
     if (!(getHeaderType(0, 0, 0) & 0x80)) {
-        printf("discovored a single pci bus\n");
-        yields();
-        // singe bus
+        printf("discovored a single pci host controller\n");
         checkBus(0);
-        return;
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
     }
-    printf("multiple pci buses are not implemented yet!\n");
     yields();
 }
diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c
index e7452b5..15713cc 100644
--- a/src/kernel/kernel.c
+++ b/src/kernel/kernel.c
@@ -20,11 +20,11 @@
     drawLogo();
     setupDevices();
     setupInterrupts();
-    printf("cpu data:\n");
     printCPUData();
-    getCurrentTask()->timerTicks = 1000;
-    getCurrentTask()->ticksLeft = 0;
     scanPCIDevices();
+    yields();
+    getCurrentTask()->timerTicks = 1000;
+    getCurrentTask()->ticksLeft = 1000;
     while (1) {
         if (isTaskQueueEmpty()) {
             asm volatile("hlt");

diff --git a/README.md b/README.md
index 8fcb978..f428588 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,11 @@
 # tree-os
 
-An open source operating system, made for x86(_64)
\ No newline at end of file
+An open source operating system, made for x86(_64) to learn about how and why modern systems what exactly they do.
+
+Right now, there exists a memory allocation system, a multitasking framework supporting messages between tasks and an interrupt system to for example allow for keyboard input.
+
+A Pci system is in progress and can currently read the bus and print out the different device types that can be found.
+
+## screenshot
+
+![](tree-os.png)
diff --git a/src/kernel/drivers/cpu/cpuid.c b/src/kernel/drivers/cpu/cpuid.c
index 2ab6e70..436aa2e 100644
--- a/src/kernel/drivers/cpu/cpuid.c
+++ b/src/kernel/drivers/cpu/cpuid.c
@@ -4,11 +4,9 @@
 
 extern void getVendorId(char *string);
 
+char *vendorID = "xxxxxxxxxxxx";
+
 void printCPUData() {
-    char *vendorID = malloc(13 * sizeof(char));
-    vendorID[12] = 0x00;
     getVendorId(vendorID);
     printf("vendor id: %s\n", vendorID);
-    free(vendorID);
-    yields();
 }
diff --git a/src/kernel/drivers/pci/pci.c b/src/kernel/drivers/pci/pci.c
index c0b4336..eb49162 100644
--- a/src/kernel/drivers/pci/pci.c
+++ b/src/kernel/drivers/pci/pci.c
@@ -5,59 +5,94 @@
 #include <task.h>
 #include <util.h>
 
-uint8_t pciConfigReadByte(uint8_t bus, uint8_t device, uint8_t function,
-                          uint8_t offset) {
-    uint32_t lbus = (uint32_t)bus;
-    uint32_t lslot = (uint32_t)device;
-    uint32_t lfunc = (uint32_t)function;
+char *classNames[] = {
+    "Unclassified",
+    "Mass Storage Controller",
+    "Network controller",
+    "Display controller",
+    "Multimedia controller",
+    "Memory Controller",
+    "Bridge",
+    "Simple Communication controller",
+    "Base System Peripheral",
+    "Input Device controller",
+    "Docking station",
+    "Processor",
+    "Serial bus controller",
+    "Wireless controller",
+    "intelligent controller",
+    "sattelite communication controller",
+    "encryption controller",
+    "signal processing controller",
+    "processing accelerator",
+    "non-essential instrumentation",
+};
 
-    uint32_t address = (uint32_t)((lbus << 16) | (lslot << 11) | (lfunc << 8) |
-                                  (offset & 0xFC) | ((uint32_t)0x80000000));
+uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
+                          uint8_t offset) {
+    uint32_t address = ((bus << 16) | (device << 11) | (function << 8) |
+                        (offset & 0xFC) | 0x80000000);
+    asm("cli");
     outi(0xCF8, address);
-    ioWait();
-    return (uint8_t)(ini(0xCFC) >> ((offset & 3) * 8));
+    uint8_t result = (ini(0xCFC) >> ((offset % 4) * 8));
+    asm("sti");
+    return result;
 }
 
 uint16_t pciConfigReadWord(uint8_t bus, uint8_t device, uint8_t function,
                            uint8_t offset) {
-    return (uint16_t)pciConfigReadByte(bus, device, function, offset) << 8 |
-           (uint16_t)pciConfigReadByte(bus, device, function, offset + 1);
+    return (uint16_t)pciConfigReadByte(bus, device, function, offset) |
+           ((uint16_t)pciConfigReadByte(bus, device, function, offset + 1)
+            << 8);
 }
 
 uint8_t getHeaderType(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadByte(bus, device, function, 0x0D);
+    return pciConfigReadByte(bus, device, function, 0x0E);
 }
 
 uint16_t getVendorID(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadWord(bus, device, function, 2);
+    return pciConfigReadWord(bus, device, function, 0);
+}
+
+void checkFunction(uint8_t bus, uint8_t device, uint8_t function) {
+    uint8_t class = pciConfigReadByte(bus, device, function, 0xB);
+    uint8_t subclass = pciConfigReadByte(bus, device, function, 0xA);
+    printf("function %i:%i:%i -> %i:%i, a %s\n", bus, device, function, class,
+           subclass, classNames[class]);
 }
 
 void checkDevice(uint8_t bus, uint8_t device) {
     uint16_t vendorID = getVendorID(bus, device, 0);
-    if (vendorID == 0xFFFF)
+    if (vendorID == 0xFFFF) {
         return;
-    printf("checking device %i;%i\n", bus, device);
+    }
+    if (getHeaderType(bus, device, 0) & 0x08) {
+        // multifunction device
+        for (int function = 0; function < 8; function++) {
+            if (getVendorID(bus, device, function) != 0xFFFF) {
+                checkFunction(bus, device, function);
+            }
+        }
+    } else {
+        checkFunction(bus, device, 0);
+    }
 }
 
 void checkBus(uint8_t bus) {
-    printf("checking bus %i...\n", bus);
-    yields();
     for (uint8_t device = 0; device < 32; device++) {
         checkDevice(bus, device);
-        yields();
     }
 }
 
 void scanPCIDevices() {
     printf("scanning pci devices...\n");
-    yields();
     if (!(getHeaderType(0, 0, 0) & 0x80)) {
-        printf("discovored a single pci bus\n");
-        yields();
-        // singe bus
+        printf("discovored a single pci host controller\n");
         checkBus(0);
-        return;
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
     }
-    printf("multiple pci buses are not implemented yet!\n");
     yields();
 }
diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c
index e7452b5..15713cc 100644
--- a/src/kernel/kernel.c
+++ b/src/kernel/kernel.c
@@ -20,11 +20,11 @@
     drawLogo();
     setupDevices();
     setupInterrupts();
-    printf("cpu data:\n");
     printCPUData();
-    getCurrentTask()->timerTicks = 1000;
-    getCurrentTask()->ticksLeft = 0;
     scanPCIDevices();
+    yields();
+    getCurrentTask()->timerTicks = 1000;
+    getCurrentTask()->ticksLeft = 1000;
     while (1) {
         if (isTaskQueueEmpty()) {
             asm volatile("hlt");
diff --git a/src/kernel/task/osTasks.c b/src/kernel/task/osTasks.c
index da46b2e..37ab866 100644
--- a/src/kernel/task/osTasks.c
+++ b/src/kernel/task/osTasks.c
@@ -26,6 +26,8 @@
 
 void initOSTasks() {
     setRunningTask(&mainTask);
+    mainTask.ticksLeft = -1;
+    mainTask.timerTicks = -1;
     keyboardConsumer = &mainTask;
     createTask(&printerTask, (uint32_t)printLoop, 0x0, 0x0);
     schedule(&printerTask);

diff --git a/README.md b/README.md
index 8fcb978..f428588 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,11 @@
 # tree-os
 
-An open source operating system, made for x86(_64)
\ No newline at end of file
+An open source operating system, made for x86(_64) to learn about how and why modern systems what exactly they do.
+
+Right now, there exists a memory allocation system, a multitasking framework supporting messages between tasks and an interrupt system to for example allow for keyboard input.
+
+A Pci system is in progress and can currently read the bus and print out the different device types that can be found.
+
+## screenshot
+
+![](tree-os.png)
diff --git a/src/kernel/drivers/cpu/cpuid.c b/src/kernel/drivers/cpu/cpuid.c
index 2ab6e70..436aa2e 100644
--- a/src/kernel/drivers/cpu/cpuid.c
+++ b/src/kernel/drivers/cpu/cpuid.c
@@ -4,11 +4,9 @@
 
 extern void getVendorId(char *string);
 
+char *vendorID = "xxxxxxxxxxxx";
+
 void printCPUData() {
-    char *vendorID = malloc(13 * sizeof(char));
-    vendorID[12] = 0x00;
     getVendorId(vendorID);
     printf("vendor id: %s\n", vendorID);
-    free(vendorID);
-    yields();
 }
diff --git a/src/kernel/drivers/pci/pci.c b/src/kernel/drivers/pci/pci.c
index c0b4336..eb49162 100644
--- a/src/kernel/drivers/pci/pci.c
+++ b/src/kernel/drivers/pci/pci.c
@@ -5,59 +5,94 @@
 #include <task.h>
 #include <util.h>
 
-uint8_t pciConfigReadByte(uint8_t bus, uint8_t device, uint8_t function,
-                          uint8_t offset) {
-    uint32_t lbus = (uint32_t)bus;
-    uint32_t lslot = (uint32_t)device;
-    uint32_t lfunc = (uint32_t)function;
+char *classNames[] = {
+    "Unclassified",
+    "Mass Storage Controller",
+    "Network controller",
+    "Display controller",
+    "Multimedia controller",
+    "Memory Controller",
+    "Bridge",
+    "Simple Communication controller",
+    "Base System Peripheral",
+    "Input Device controller",
+    "Docking station",
+    "Processor",
+    "Serial bus controller",
+    "Wireless controller",
+    "intelligent controller",
+    "sattelite communication controller",
+    "encryption controller",
+    "signal processing controller",
+    "processing accelerator",
+    "non-essential instrumentation",
+};
 
-    uint32_t address = (uint32_t)((lbus << 16) | (lslot << 11) | (lfunc << 8) |
-                                  (offset & 0xFC) | ((uint32_t)0x80000000));
+uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
+                          uint8_t offset) {
+    uint32_t address = ((bus << 16) | (device << 11) | (function << 8) |
+                        (offset & 0xFC) | 0x80000000);
+    asm("cli");
     outi(0xCF8, address);
-    ioWait();
-    return (uint8_t)(ini(0xCFC) >> ((offset & 3) * 8));
+    uint8_t result = (ini(0xCFC) >> ((offset % 4) * 8));
+    asm("sti");
+    return result;
 }
 
 uint16_t pciConfigReadWord(uint8_t bus, uint8_t device, uint8_t function,
                            uint8_t offset) {
-    return (uint16_t)pciConfigReadByte(bus, device, function, offset) << 8 |
-           (uint16_t)pciConfigReadByte(bus, device, function, offset + 1);
+    return (uint16_t)pciConfigReadByte(bus, device, function, offset) |
+           ((uint16_t)pciConfigReadByte(bus, device, function, offset + 1)
+            << 8);
 }
 
 uint8_t getHeaderType(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadByte(bus, device, function, 0x0D);
+    return pciConfigReadByte(bus, device, function, 0x0E);
 }
 
 uint16_t getVendorID(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadWord(bus, device, function, 2);
+    return pciConfigReadWord(bus, device, function, 0);
+}
+
+void checkFunction(uint8_t bus, uint8_t device, uint8_t function) {
+    uint8_t class = pciConfigReadByte(bus, device, function, 0xB);
+    uint8_t subclass = pciConfigReadByte(bus, device, function, 0xA);
+    printf("function %i:%i:%i -> %i:%i, a %s\n", bus, device, function, class,
+           subclass, classNames[class]);
 }
 
 void checkDevice(uint8_t bus, uint8_t device) {
     uint16_t vendorID = getVendorID(bus, device, 0);
-    if (vendorID == 0xFFFF)
+    if (vendorID == 0xFFFF) {
         return;
-    printf("checking device %i;%i\n", bus, device);
+    }
+    if (getHeaderType(bus, device, 0) & 0x08) {
+        // multifunction device
+        for (int function = 0; function < 8; function++) {
+            if (getVendorID(bus, device, function) != 0xFFFF) {
+                checkFunction(bus, device, function);
+            }
+        }
+    } else {
+        checkFunction(bus, device, 0);
+    }
 }
 
 void checkBus(uint8_t bus) {
-    printf("checking bus %i...\n", bus);
-    yields();
     for (uint8_t device = 0; device < 32; device++) {
         checkDevice(bus, device);
-        yields();
     }
 }
 
 void scanPCIDevices() {
     printf("scanning pci devices...\n");
-    yields();
     if (!(getHeaderType(0, 0, 0) & 0x80)) {
-        printf("discovored a single pci bus\n");
-        yields();
-        // singe bus
+        printf("discovored a single pci host controller\n");
         checkBus(0);
-        return;
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
     }
-    printf("multiple pci buses are not implemented yet!\n");
     yields();
 }
diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c
index e7452b5..15713cc 100644
--- a/src/kernel/kernel.c
+++ b/src/kernel/kernel.c
@@ -20,11 +20,11 @@
     drawLogo();
     setupDevices();
     setupInterrupts();
-    printf("cpu data:\n");
     printCPUData();
-    getCurrentTask()->timerTicks = 1000;
-    getCurrentTask()->ticksLeft = 0;
     scanPCIDevices();
+    yields();
+    getCurrentTask()->timerTicks = 1000;
+    getCurrentTask()->ticksLeft = 1000;
     while (1) {
         if (isTaskQueueEmpty()) {
             asm volatile("hlt");
diff --git a/src/kernel/task/osTasks.c b/src/kernel/task/osTasks.c
index da46b2e..37ab866 100644
--- a/src/kernel/task/osTasks.c
+++ b/src/kernel/task/osTasks.c
@@ -26,6 +26,8 @@
 
 void initOSTasks() {
     setRunningTask(&mainTask);
+    mainTask.ticksLeft = -1;
+    mainTask.timerTicks = -1;
     keyboardConsumer = &mainTask;
     createTask(&printerTask, (uint32_t)printLoop, 0x0, 0x0);
     schedule(&printerTask);
diff --git a/src/kernel/task/task.c b/src/kernel/task/task.c
index 47f2f69..e001f9f 100644
--- a/src/kernel/task/task.c
+++ b/src/kernel/task/task.c
@@ -26,7 +26,7 @@
     task->stack = stack;
     task->messages = NULL;
     task->ticksLeft = -1;
-    task->timerTicks = 0;
+    task->timerTicks = -1;
 }
 
 void yield() {

diff --git a/README.md b/README.md
index 8fcb978..f428588 100644
--- a/README.md
+++ b/README.md
@@ -1,3 +1,11 @@
 # tree-os
 
-An open source operating system, made for x86(_64)
\ No newline at end of file
+An open source operating system, made for x86(_64) to learn about how and why modern systems what exactly they do.
+
+Right now, there exists a memory allocation system, a multitasking framework supporting messages between tasks and an interrupt system to for example allow for keyboard input.
+
+A Pci system is in progress and can currently read the bus and print out the different device types that can be found.
+
+## screenshot
+
+![](tree-os.png)
diff --git a/src/kernel/drivers/cpu/cpuid.c b/src/kernel/drivers/cpu/cpuid.c
index 2ab6e70..436aa2e 100644
--- a/src/kernel/drivers/cpu/cpuid.c
+++ b/src/kernel/drivers/cpu/cpuid.c
@@ -4,11 +4,9 @@
 
 extern void getVendorId(char *string);
 
+char *vendorID = "xxxxxxxxxxxx";
+
 void printCPUData() {
-    char *vendorID = malloc(13 * sizeof(char));
-    vendorID[12] = 0x00;
     getVendorId(vendorID);
     printf("vendor id: %s\n", vendorID);
-    free(vendorID);
-    yields();
 }
diff --git a/src/kernel/drivers/pci/pci.c b/src/kernel/drivers/pci/pci.c
index c0b4336..eb49162 100644
--- a/src/kernel/drivers/pci/pci.c
+++ b/src/kernel/drivers/pci/pci.c
@@ -5,59 +5,94 @@
 #include <task.h>
 #include <util.h>
 
-uint8_t pciConfigReadByte(uint8_t bus, uint8_t device, uint8_t function,
-                          uint8_t offset) {
-    uint32_t lbus = (uint32_t)bus;
-    uint32_t lslot = (uint32_t)device;
-    uint32_t lfunc = (uint32_t)function;
+char *classNames[] = {
+    "Unclassified",
+    "Mass Storage Controller",
+    "Network controller",
+    "Display controller",
+    "Multimedia controller",
+    "Memory Controller",
+    "Bridge",
+    "Simple Communication controller",
+    "Base System Peripheral",
+    "Input Device controller",
+    "Docking station",
+    "Processor",
+    "Serial bus controller",
+    "Wireless controller",
+    "intelligent controller",
+    "sattelite communication controller",
+    "encryption controller",
+    "signal processing controller",
+    "processing accelerator",
+    "non-essential instrumentation",
+};
 
-    uint32_t address = (uint32_t)((lbus << 16) | (lslot << 11) | (lfunc << 8) |
-                                  (offset & 0xFC) | ((uint32_t)0x80000000));
+uint8_t pciConfigReadByte(uint32_t bus, uint32_t device, uint32_t function,
+                          uint8_t offset) {
+    uint32_t address = ((bus << 16) | (device << 11) | (function << 8) |
+                        (offset & 0xFC) | 0x80000000);
+    asm("cli");
     outi(0xCF8, address);
-    ioWait();
-    return (uint8_t)(ini(0xCFC) >> ((offset & 3) * 8));
+    uint8_t result = (ini(0xCFC) >> ((offset % 4) * 8));
+    asm("sti");
+    return result;
 }
 
 uint16_t pciConfigReadWord(uint8_t bus, uint8_t device, uint8_t function,
                            uint8_t offset) {
-    return (uint16_t)pciConfigReadByte(bus, device, function, offset) << 8 |
-           (uint16_t)pciConfigReadByte(bus, device, function, offset + 1);
+    return (uint16_t)pciConfigReadByte(bus, device, function, offset) |
+           ((uint16_t)pciConfigReadByte(bus, device, function, offset + 1)
+            << 8);
 }
 
 uint8_t getHeaderType(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadByte(bus, device, function, 0x0D);
+    return pciConfigReadByte(bus, device, function, 0x0E);
 }
 
 uint16_t getVendorID(uint8_t bus, uint8_t device, uint8_t function) {
-    return pciConfigReadWord(bus, device, function, 2);
+    return pciConfigReadWord(bus, device, function, 0);
+}
+
+void checkFunction(uint8_t bus, uint8_t device, uint8_t function) {
+    uint8_t class = pciConfigReadByte(bus, device, function, 0xB);
+    uint8_t subclass = pciConfigReadByte(bus, device, function, 0xA);
+    printf("function %i:%i:%i -> %i:%i, a %s\n", bus, device, function, class,
+           subclass, classNames[class]);
 }
 
 void checkDevice(uint8_t bus, uint8_t device) {
     uint16_t vendorID = getVendorID(bus, device, 0);
-    if (vendorID == 0xFFFF)
+    if (vendorID == 0xFFFF) {
         return;
-    printf("checking device %i;%i\n", bus, device);
+    }
+    if (getHeaderType(bus, device, 0) & 0x08) {
+        // multifunction device
+        for (int function = 0; function < 8; function++) {
+            if (getVendorID(bus, device, function) != 0xFFFF) {
+                checkFunction(bus, device, function);
+            }
+        }
+    } else {
+        checkFunction(bus, device, 0);
+    }
 }
 
 void checkBus(uint8_t bus) {
-    printf("checking bus %i...\n", bus);
-    yields();
     for (uint8_t device = 0; device < 32; device++) {
         checkDevice(bus, device);
-        yields();
     }
 }
 
 void scanPCIDevices() {
     printf("scanning pci devices...\n");
-    yields();
     if (!(getHeaderType(0, 0, 0) & 0x80)) {
-        printf("discovored a single pci bus\n");
-        yields();
-        // singe bus
+        printf("discovored a single pci host controller\n");
         checkBus(0);
-        return;
+    } else {
+        for (uint8_t bus = 0; bus < 8; bus++) {
+            checkBus(bus);
+        }
     }
-    printf("multiple pci buses are not implemented yet!\n");
     yields();
 }
diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c
index e7452b5..15713cc 100644
--- a/src/kernel/kernel.c
+++ b/src/kernel/kernel.c
@@ -20,11 +20,11 @@
     drawLogo();
     setupDevices();
     setupInterrupts();
-    printf("cpu data:\n");
     printCPUData();
-    getCurrentTask()->timerTicks = 1000;
-    getCurrentTask()->ticksLeft = 0;
     scanPCIDevices();
+    yields();
+    getCurrentTask()->timerTicks = 1000;
+    getCurrentTask()->ticksLeft = 1000;
     while (1) {
         if (isTaskQueueEmpty()) {
             asm volatile("hlt");
diff --git a/src/kernel/task/osTasks.c b/src/kernel/task/osTasks.c
index da46b2e..37ab866 100644
--- a/src/kernel/task/osTasks.c
+++ b/src/kernel/task/osTasks.c
@@ -26,6 +26,8 @@
 
 void initOSTasks() {
     setRunningTask(&mainTask);
+    mainTask.ticksLeft = -1;
+    mainTask.timerTicks = -1;
     keyboardConsumer = &mainTask;
     createTask(&printerTask, (uint32_t)printLoop, 0x0, 0x0);
     schedule(&printerTask);
diff --git a/src/kernel/task/task.c b/src/kernel/task/task.c
index 47f2f69..e001f9f 100644
--- a/src/kernel/task/task.c
+++ b/src/kernel/task/task.c
@@ -26,7 +26,7 @@
     task->stack = stack;
     task->messages = NULL;
     task->ticksLeft = -1;
-    task->timerTicks = 0;
+    task->timerTicks = -1;
 }
 
 void yield() {
diff --git a/tree-os.png b/tree-os.png
new file mode 100644
index 0000000..c586f31
--- /dev/null
+++ b/tree-os.png
Binary files differ