diff --git a/configure.ac b/configure.ac
index da0d2df..47e3279 100644
--- a/configure.ac
+++ b/configure.ac
@@ -13,7 +13,7 @@ AC_PATH_PROG(PKG_CONFIG, pkg-config)
 
 # Checks for header files.
 AC_HEADER_STDC
-AC_CHECK_HEADERS([stdlib.h])
+AC_CHECK_HEADERS([stdlib.h stdint.h])
 
 
 # libusb
@@ -40,10 +40,11 @@ AC_MSG_RESULT($enable_debug)
  
 if test "x$enable_debug" = "xyes"
 then
-        CFLAGS="$CFLAGS -g -Wall -DDEBUG"
+        CFLAGS="$CFLAGS -g -Wall -DDEBUG -pedantic"
 fi
 AC_SUBST([DEBUG_CFLAGS])
 
+CFLAGS="$CFLAGS -std=c99"
 
 AC_CONFIG_FILES([
 		Makefile
diff --git a/src/anticol.c b/src/anticol.c
index e4e4e34..f05908f 100644
--- a/src/anticol.c
+++ b/src/anticol.c
@@ -20,16 +20,18 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <string.h>
+
 #include "libnfc.h"
 
 #define SAK_FLAG_ATS_SUPPORTED 0x20
 
 static byte abtRx[MAX_FRAME_LEN];
-static ui32 uiRxBits;
-static ui32 uiRxLen;
+static uint32_t uiRxBits;
+static uint32_t uiRxLen;
 static byte abtUid[10];
-static ui32 uiUidLen = 4;
+static uint32_t uiUidLen = 4;
 static dev_info* pdi;
 
 // ISO14443A Anti-Collision Commands
@@ -39,7 +41,7 @@ byte abtSelectTag [9] = { 0x93,0x70,0x00,0x00,0x00,0x00,0x00,0x00,0x00 };
 byte abtRats      [4] = { 0xe0,0x50,0xbc,0xa5 };
 byte abtHalt      [4] = { 0x50,0x00,0x57,0xcd };
 
-bool transmit_bits(const byte* pbtTx, const ui32 uiTxBits)
+bool transmit_bits(const byte* pbtTx, const uint32_t uiTxBits)
 {
   // Show transmitted command
   printf("R: "); print_hex_bits(pbtTx,uiTxBits);
@@ -55,7 +57,7 @@ bool transmit_bits(const byte* pbtTx, const ui32 uiTxBits)
 }
 
 
-bool transmit_bytes(const byte* pbtTx, const ui32 uiTxLen)
+bool transmit_bytes(const byte* pbtTx, const uint32_t uiTxLen)
 {
   // Show transmitted command
   printf("R: "); print_hex(pbtTx,uiTxLen);
diff --git a/src/bitutils.c b/src/bitutils.c
index 5fda4b1..6ce6e19 100644
--- a/src/bitutils.c
+++ b/src/bitutils.c
@@ -19,6 +19,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
 #include <stdio.h>
+
 #include "bitutils.h"
 
 const static byte OddParity[256] = {
@@ -68,9 +69,9 @@ byte oddparity(const byte bt)
   return OddParity[bt];
 }
 
-void oddparity_bytes(const byte* pbtData, const ui32 uiLen, byte* pbtPar)
+void oddparity_bytes(const byte* pbtData, const uint32_t uiLen, byte* pbtPar)
 {
-  ui32 uiByteNr;
+  uint32_t uiByteNr;
 
   // Calculate the parity bits for the command
   for (uiByteNr=0; uiByteNr<uiLen; uiByteNr++)
@@ -84,21 +85,21 @@ byte mirror(byte bt)
   return ByteMirror[bt];
 }
 
-ui32 mirror32(ui32 ui32Bits)
+uint32_t mirror32(uint32_t ui32Bits)
 {
   mirror_bytes((byte*)&ui32Bits,4);
   return ui32Bits;
 }
 
-ui64 mirror64(ui64 ui64Bits)
+uint64_t mirror64(uint64_t ui64Bits)
 {
   mirror_bytes((byte*)&ui64Bits,8);
   return ui64Bits;
 }
 
-void mirror_bytes(byte *pbts, ui32 uiLen)
+void mirror_bytes(byte *pbts, uint32_t uiLen)
 {
-  ui32 btNr;
+  uint32_t btNr;
 
   for (btNr=0; btNr<uiLen; btNr++)
   {
@@ -107,37 +108,37 @@ void mirror_bytes(byte *pbts, ui32 uiLen)
   }
 }
 
-ui32 swap_endian32(const void* pui32)
+uint32_t swap_endian32(const void* pui32)
 {
-  ui32 ui32N = *((ui32*)pui32);
+  uint32_t ui32N = *((uint32_t*)pui32);
   return (((ui32N&0xFF)<<24)+((ui32N&0xFF00)<<8)+((ui32N&0xFF0000)>>8)+((ui32N&0xFF000000)>>24));
 }
 
-ui64 swap_endian64(const void* pui64)
+uint64_t swap_endian64(const void* pui64)
 {
-  ui64 ui64N = *((ui64*)pui64);
+  uint64_t ui64N = *((uint64_t *)pui64);
   return (((ui64N&0xFF)<<56)+((ui64N&0xFF00)<<40)+((ui64N&0xFF0000)<<24)+((ui64N&0xFF000000)<<8)+((ui64N&0xFF00000000ull)>>8)+((ui64N&0xFF0000000000ull)>>24)+((ui64N&0xFF000000000000ull)>>40)+((ui64N&0xFF00000000000000ull)>>56));
 }
 
-void append_iso14443a_crc(byte* pbtData, ui32 uiLen)
+void append_iso14443a_crc(byte* pbtData, uint32_t uiLen)
 {
   byte bt;
-  ui32 wCrc = 0x6363;
+  uint32_t wCrc = 0x6363;
 
   do {
     bt = *pbtData++;
     bt = (bt^(byte)(wCrc & 0x00FF));
     bt = (bt^(bt<<4));
-    wCrc = (wCrc >> 8)^((ui32)bt << 8)^((ui32)bt<<3)^((ui32)bt>>4);
+    wCrc = (wCrc >> 8)^((uint32_t)bt << 8)^((uint32_t)bt<<3)^((uint32_t)bt>>4);
   } while (--uiLen);
 
   *pbtData++ = (byte) (wCrc & 0xFF);
   *pbtData = (byte) ((wCrc >> 8) & 0xFF);
 }
 
-void print_hex(const byte* pbtData, const ui32 uiBytes)
+void print_hex(const byte* pbtData, const uint32_t uiBytes)
 {
-  ui32 uiPos;
+  uint32_t uiPos;
 
   for (uiPos=0; uiPos < uiBytes; uiPos++)
   {
@@ -146,10 +147,10 @@ void print_hex(const byte* pbtData, const ui32 uiBytes)
   printf("\n");
 }
 
-void print_hex_bits(const byte* pbtData, const ui32 uiBits)
+void print_hex_bits(const byte* pbtData, const uint32_t uiBits)
 {
-  ui32 uiPos;
-  ui32 uiBytes = uiBits/8;
+  uint32_t uiPos;
+  uint32_t uiBytes = uiBits/8;
 
   for (uiPos=0; uiPos < uiBytes; uiPos++)
   {
@@ -162,10 +163,10 @@ void print_hex_bits(const byte* pbtData, const ui32 uiBits)
   printf("\n");
 }
 
-void print_hex_par(const byte* pbtData, const ui32 uiBits, const byte* pbtDataPar)
+void print_hex_par(const byte* pbtData, const uint32_t uiBits, const byte* pbtDataPar)
 {
-  ui32 uiPos;
-  ui32 uiBytes = uiBits/8;
+  uint32_t uiPos;
+  uint32_t uiBytes = uiBits/8;
 
   for (uiPos=0; uiPos < uiBytes; uiPos++)
   {
diff --git a/src/bitutils.h b/src/bitutils.h
index 312c968..8cd6d97 100644
--- a/src/bitutils.h
+++ b/src/bitutils.h
@@ -21,24 +21,26 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #ifndef _LIBNFC_BITUTILS_H_
 #define _LIBNFC_BITUTILS_H_
 
+#include <stdint.h>
+
 #include "defines.h"
 
 byte oddparity(const byte bt);
-void oddparity_bytes(const byte* pbtData, const ui32 uiLen, byte* pbtPar);
+void oddparity_bytes(const byte* pbtData, const uint32_t uiLen, byte* pbtPar);
 
 byte mirror(byte bt);
-ui32 mirror32(ui32 ui32Bits);
-ui64 mirror64(ui64 ui64Bits);
-void mirror_bytes(byte *pbts, ui32 uiLen);
+uint32_t mirror32(uint32_t ui32Bits);
+uint64_t mirror64(uint64_t ui64Bits);
+void mirror_bytes(byte *pbts, uint32_t uiLen);
 
-ui32 swap_endian32(const void* pui32);
-ui64 swap_endian64(const void* pui64);
+uint32_t swap_endian32(const void* pui32);
+uint64_t swap_endian64(const void* pui64);
 
-void append_iso14443a_crc(byte* pbtData, ui32 uiLen);
+void append_iso14443a_crc(byte* pbtData, uint32_t uiLen);
 
-void print_hex(const byte* pbtData, const ui32 uiLen);
-void print_hex_bits(const byte* pbtData, const ui32 uiBits);
-void print_hex_par(const byte* pbtData, const ui32 uiBits, const byte* pbtDataPar);
+void print_hex(const byte* pbtData, const uint32_t uiLen);
+void print_hex_bits(const byte* pbtData, const uint32_t uiBits);
+void print_hex_par(const byte* pbtData, const uint32_t uiBits, const byte* pbtDataPar);
 
 #endif // _LIBNFC_BITUTILS_H_
 
diff --git a/src/defines.h b/src/defines.h
index 2c63865..cddea0e 100644
--- a/src/defines.h
+++ b/src/defines.h
@@ -24,14 +24,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 // #define DEBUG
 
 typedef unsigned char       byte;
-typedef unsigned char       ui8;
-typedef unsigned short      ui16;
-typedef unsigned int        ui32;
-typedef unsigned long long  ui64;
 typedef unsigned long       ulong;
-typedef char                i8;
-typedef short               i16;
-typedef int                 i32;
 
 #define null 0
 
diff --git a/src/dev_acr122.c b/src/dev_acr122.c
index cb2495a..18e6181 100644
--- a/src/dev_acr122.c
+++ b/src/dev_acr122.c
@@ -57,15 +57,15 @@ static ulong ulRxBufLen;
 static byte abtGetFw[5] = { 0xFF,0x00,0x48,0x00,0x00 };
 static byte abtLed[9] = { 0xFF,0x00,0x40,0x05,0x04,0x00,0x00,0x00,0x00 };
 
-dev_info* dev_acr122_connect(const ui32 uiIndex)
+dev_info* dev_acr122_connect(const uint32_t uiIndex)
 {
   char* pacReaders[MAX_READERS];
   char acList[256+64*MAX_READERS];
   ulong ulListLen = sizeof(acList);
-  ui32 uiPos;
-  ui32 uiReaderCount;
-  ui32 uiReader;
-  ui32 uiDevIndex;
+  uint32_t uiPos;
+  uint32_t uiReaderCount;
+  uint32_t uiReader;
+  uint32_t uiDevIndex;
   dev_info* pdi;
   dev_spec_acr122* pdsa;
   dev_spec_acr122 dsa;
@@ -172,7 +172,7 @@ void dev_acr122_disconnect(dev_info* pdi)
   free(pdi);
 }
 
-bool dev_acr122_transceive(const dev_spec ds, const byte* pbtTx, const ui32 uiTxLen, byte* pbtRx, ui32* puiRxLen)
+bool dev_acr122_transceive(const dev_spec ds, const byte* pbtTx, const uint32_t uiTxLen, byte* pbtRx, uint32_t* puiRxLen)
 {
   dev_spec_acr122* pdsa = (dev_spec_acr122*)ds;
 
@@ -231,7 +231,7 @@ bool dev_acr122_transceive(const dev_spec ds, const byte* pbtTx, const ui32 uiTx
 
 char* dev_acr122_firmware(const dev_spec ds)
 {
-  ui32 uiResult;
+  uint32_t uiResult;
   
   dev_spec_acr122* pdsa = (dev_spec_acr122*)ds;
   static char abtFw[11];
diff --git a/src/dev_acr122.h b/src/dev_acr122.h
index 95c763d..02e1b50 100644
--- a/src/dev_acr122.h
+++ b/src/dev_acr122.h
@@ -21,15 +21,17 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #ifndef _LIBNFC_DEV_ACR122_H_
 #define _LIBNFC_DEV_ACR122_H_
 
+#include <stdint.h>
+
 #include "defines.h"
 #include "types.h"
 
 // Functions used by developer to handle connection to this device
-dev_info* dev_acr122_connect(const ui32 uiIndex);
+dev_info* dev_acr122_connect(const uint32_t uiIndex);
 void dev_acr122_disconnect(dev_info* pdi);
 
 // Callback function used by libnfc to transmit commands to the PN53X chip
-bool dev_acr122_transceive(const dev_spec ds, const byte* pbtTx, const ui32 uiTxLen, byte* pbtRx, ui32* puiRxLen);
+bool dev_acr122_transceive(const dev_spec ds, const byte* pbtTx, const uint32_t uiTxLen, byte* pbtRx, uint32_t* puiRxLen);
 
 // Various additional features this device supports
 char* dev_acr122_firmware(const dev_spec ds);
diff --git a/src/dev_pn531.c b/src/dev_pn531.c
index a6d3bd0..67791e9 100644
--- a/src/dev_pn531.c
+++ b/src/dev_pn531.c
@@ -34,15 +34,15 @@ static char buffer[BUFFER_LENGTH] = { 0x00, 0x00, 0xff }; // Every packet must s
 
 typedef struct {
   usb_dev_handle* pudh;
-  ui32 uiEndPointIn;
-  ui32 uiEndPointOut;
+  uint32_t uiEndPointIn;
+  uint32_t uiEndPointOut;
 } dev_spec_pn531;
 
 // Find transfer endpoints for bulk transfers
 void get_end_points(struct usb_device *dev, dev_spec_pn531* pdsp)
 {
-  ui32 uiIndex;
-  ui32 uiEndPoint;
+  uint32_t uiIndex;
+  uint32_t uiEndPoint;
   struct usb_interface_descriptor* puid = dev->config->interface->altsetting;
 
   // 3 Endpoints maximum: Interrupt In, Bulk In, Bulk Out
@@ -74,7 +74,7 @@ void get_end_points(struct usb_device *dev, dev_spec_pn531* pdsp)
   }
 }                                                                                  
 
-dev_info* dev_pn531_connect(const ui32 uiIndex)
+dev_info* dev_pn531_connect(const uint32_t uiIndex)
 {                                                
   int idvendor = 0x04CC;
   int idproduct = 0x0531;
@@ -83,7 +83,7 @@ dev_info* dev_pn531_connect(const ui32 uiIndex)
   dev_info* pdi = INVALID_DEVICE_INFO;
   dev_spec_pn531* pdsp;
   dev_spec_pn531 dsp;
-  ui32 uiDevIndex;
+  uint32_t uiDevIndex;
 
   dsp.uiEndPointIn = 0;
   dsp.uiEndPointOut = 0;
@@ -164,9 +164,9 @@ void dev_pn531_disconnect(dev_info* pdi)
   free(pdi);
 }                                        
 
-bool dev_pn531_transceive(const dev_spec ds, const byte* pbtTx, const ui32 uiTxLen, byte* pbtRx, ui32* puiRxLen)
+bool dev_pn531_transceive(const dev_spec ds, const byte* pbtTx, const uint32_t uiTxLen, byte* pbtRx, uint32_t* puiRxLen)
 {                                                                          
-    ui32 uiPos = 0;                                                             
+    uint32_t uiPos = 0;                                                             
     int ret = 0;                                                           
     char buf[BUFFER_LENGTH];
     dev_spec_pn531* pdsp = (dev_spec_pn531*)ds;
diff --git a/src/dev_pn531.h b/src/dev_pn531.h
index 65419c4..33ab49e 100644
--- a/src/dev_pn531.h
+++ b/src/dev_pn531.h
@@ -21,15 +21,17 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #ifndef _LIBNFC_DEV_PN531_H_
 #define _LIBNFC_DEV_PN531_H_
 
+#include <stdint.h>
+
 #include "defines.h"
 #include "types.h"
 
 // Functions used by developer to handle connection to this device
-dev_info* dev_pn531_connect(const ui32 uiIndex);
+dev_info* dev_pn531_connect(const uint32_t uiIndex);
 void dev_pn531_disconnect(dev_info* pdi);
 
 // Callback function used by libnfc to transmit commands to the PN53X chip
-bool dev_pn531_transceive(const dev_spec ds, const byte* pbtTx, const ui32 uiTxLen, byte* pbtRx, ui32* puiRxLen);
+bool dev_pn531_transceive(const dev_spec ds, const byte* pbtTx, const uint32_t uiTxLen, byte* pbtRx, uint32_t* puiRxLen);
 
 #endif // _LIBNFC_DEV_PN531_H_
 
diff --git a/src/emulate.c b/src/emulate.c
index 5153ba9..134912a 100644
--- a/src/emulate.c
+++ b/src/emulate.c
@@ -20,11 +20,13 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <string.h>
+
 #include "libnfc.h"
 
 static byte abtRecv[MAX_FRAME_LEN];
-static ui32 uiRecvBits;
+static uint32_t uiRecvBits;
 static dev_info* pdi;
 
 // ISO14443A Anti-Collision response
@@ -35,7 +37,7 @@ byte abtSak       [9] = { 0x08,0xb6,0xdd };
 int main(int argc, const char* argv[])
 {                       
   byte* pbtTx = null;
-  ui32 uiTxBits;
+  uint32_t uiTxBits;
   
   // Try to open the NFC reader
   pdi = nfc_connect();
diff --git a/src/libnfc.c b/src/libnfc.c
index 8d87140..f83dcd6 100644
--- a/src/libnfc.c
+++ b/src/libnfc.c
@@ -88,9 +88,9 @@ byte pncmd_exchange_raw_data          [266] = { 0xD4,0x42 };
 // Global buffers used for communication with the PN53X chip
 #define MAX_FRAME_LEN 264
 static byte abtRx[MAX_FRAME_LEN];
-static ui32 uiRxLen;
+static uint32_t uiRxLen;
 
-bool pn53x_transceive(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxLen)
+bool pn53x_transceive(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxLen)
 {
   // Reset the receiving buffer
   uiRxLen = MAX_FRAME_LEN;
@@ -105,17 +105,17 @@ bool pn53x_transceive(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxLen
   return true;
 }
 
-byte pn53x_get_reg(const dev_info* pdi, ui16 ui16Reg)
+byte pn53x_get_reg(const dev_info* pdi, uint16_t ui16Reg)
 {
-  ui8 ui8Value;
-  ui32 uiValueLen = 1;
+  uint8_t ui8Value;
+  uint32_t uiValueLen = 1;
   pncmd_get_register[2] = ui16Reg >> 8;
   pncmd_get_register[3] = ui16Reg & 0xff;
   pdi->pdc->transceive(pdi->ds,pncmd_get_register,4,&ui8Value,&uiValueLen);
   return ui8Value;
 }
 
-bool pn53x_set_reg(const dev_info* pdi, ui16 ui16Reg, ui8 ui8SybmolMask, ui8 ui8Value)
+bool pn53x_set_reg(const dev_info* pdi, uint16_t ui16Reg, uint8_t ui8SybmolMask, uint8_t ui8Value)
 {
   pncmd_set_register[2] = ui16Reg >> 8;
   pncmd_set_register[3] = ui16Reg & 0xff;
@@ -123,13 +123,13 @@ bool pn53x_set_reg(const dev_info* pdi, ui16 ui16Reg, ui8 ui8SybmolMask, ui8 ui8
   return pdi->pdc->transceive(pdi->ds,pncmd_set_register,5,null,null);
 }
 
-bool pn53x_set_parameters(const dev_info* pdi, ui8 ui8Value)
+bool pn53x_set_parameters(const dev_info* pdi, uint8_t ui8Value)
 {
   pncmd_set_parameters[2] = ui8Value;
   return pdi->pdc->transceive(pdi->ds,pncmd_set_parameters,3,null,null);
 }
 
-bool pn53x_set_tx_bits(const dev_info* pdi, ui8 ui8Bits)
+bool pn53x_set_tx_bits(const dev_info* pdi, uint8_t ui8Bits)
 {
   // Test if we need to update the transmission bits register setting
   if (pdi->ui8TxBits != ui8Bits)
@@ -143,13 +143,13 @@ bool pn53x_set_tx_bits(const dev_info* pdi, ui8 ui8Bits)
   return true;
 }
 
-bool pn53x_wrap_frame(const byte* pbtTx, const ui32 uiTxBits, const byte* pbtTxPar, byte* pbtFrame, ui32* puiFrameBits)
+bool pn53x_wrap_frame(const byte* pbtTx, const uint32_t uiTxBits, const byte* pbtTxPar, byte* pbtFrame, uint32_t* puiFrameBits)
 {
   byte btFrame;
   byte btData;
-  ui32 uiBitPos;
-  ui32 uiDataPos = 0;
-  ui32 uiBitsLeft = uiTxBits;
+  uint32_t uiBitPos;
+  uint32_t uiDataPos = 0;
+  uint32_t uiBitsLeft = uiTxBits;
 
   // Make sure we should frame at least something
   if (uiBitsLeft == 0) return false;
@@ -199,14 +199,14 @@ bool pn53x_wrap_frame(const byte* pbtTx, const ui32 uiTxBits, const byte* pbtTxP
   }
 }
 
-bool pn53x_unwrap_frame(const byte* pbtFrame, const ui32 uiFrameBits, byte* pbtRx, ui32* puiRxBits, byte* pbtRxPar)
+bool pn53x_unwrap_frame(const byte* pbtFrame, const uint32_t uiFrameBits, byte* pbtRx, uint32_t* puiRxBits, byte* pbtRxPar)
 {
   byte btFrame;
   byte btData;
-  ui8 uiBitPos;
-  ui32 uiDataPos = 0;
+  uint8_t uiBitPos;
+  uint32_t uiDataPos = 0;
   byte* pbtFramePos = (byte*) pbtFrame;
-  ui32 uiBitsLeft = uiFrameBits;
+  uint32_t uiBitsLeft = uiFrameBits;
 
   // Make sure we should frame at least something
   if (uiBitsLeft == 0) return false;
@@ -248,9 +248,9 @@ bool pn53x_unwrap_frame(const byte* pbtFrame, const ui32 uiFrameBits, byte* pbtR
 dev_info* nfc_connect()
 {
   dev_info* pdi;
-  ui32 uiDev;
+  uint32_t uiDev;
   byte abtFw[4];
-  ui32 uiFwLen = sizeof(abtFw);
+  uint32_t uiFwLen = sizeof(abtFw);
   
   // Search through the device list for an available device
   for (uiDev=0; uiDev<sizeof(dev_callbacks_list)/sizeof(dev_callbacks_list[0]); uiDev++)
@@ -379,7 +379,7 @@ bool nfc_reader_init(const dev_info* pdi)
   return true;
 }
 
-bool nfc_reader_select(const dev_info* pdi, const init_modulation im, const byte* pbtInitData, const ui32 uiInitDataLen, tag_info* pti)
+bool nfc_reader_select(const dev_info* pdi, const init_modulation im, const byte* pbtInitData, const uint32_t uiInitDataLen, tag_info* pti)
 {
 	// Make sure we are dealing with a active device
   if (!pdi->bActive) return false;
@@ -480,11 +480,11 @@ bool nfc_reader_deselect(const dev_info* pdi)
   return (pdi->pdc->transceive(pdi->ds,pncmd_reader_deselect,3,null,null));
 }
 
-bool nfc_reader_transceive_bits(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxBits, const byte* pbtTxPar, byte* pbtRx, ui32* puiRxBits, byte* pbtRxPar)
+bool nfc_reader_transceive_bits(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxBits, const byte* pbtTxPar, byte* pbtRx, uint32_t* puiRxBits, byte* pbtRxPar)
 {
-  ui32 uiFrameBits = 0;
-  ui32 uiFrameBytes = 0;
-  ui8 ui8Bits = 0;
+  uint32_t uiFrameBits = 0;
+  uint32_t uiFrameBytes = 0;
+  uint8_t ui8Bits = 0;
 
   // Check if we should prepare the parity bits ourself
   if (!pdi->bPar)
@@ -534,7 +534,7 @@ bool nfc_reader_transceive_bits(const dev_info* pdi, const byte* pbtTx, const ui
   return true;
 }
 
-bool nfc_reader_transceive_bytes(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxLen, byte* pbtRx, ui32* puiRxLen)
+bool nfc_reader_transceive_bytes(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxLen, byte* pbtRx, uint32_t* puiRxLen)
 {
   // We can not just send bytes without parity if while the PN53X expects we handled them
   if (!pdi->bPar) return false;
@@ -559,9 +559,9 @@ bool nfc_reader_transceive_bytes(const dev_info* pdi, const byte* pbtTx, const u
   return true;
 }
 
-bool nfc_reader_mifare_cmd(const dev_info* pdi, const mifare_cmd mc, const ui8 ui8Block, mifare_param* pmp)
+bool nfc_reader_mifare_cmd(const dev_info* pdi, const mifare_cmd mc, const uint8_t ui8Block, mifare_param* pmp)
 {
-  ui32 uiParamLen;
+  uint32_t uiParamLen;
 
 	// Make sure we are dealing with a active device
   if (!pdi->bActive) return false;
@@ -615,9 +615,9 @@ bool nfc_reader_mifare_cmd(const dev_info* pdi, const mifare_cmd mc, const ui8 u
   return true;
 }
 
-bool nfc_target_init(const dev_info* pdi, byte* pbtRx, ui32* puiRxBits)
+bool nfc_target_init(const dev_info* pdi, byte* pbtRx, uint32_t* puiRxBits)
 {
-  ui8 ui8Bits;
+  uint8_t ui8Bits;
 
   // Save the current configuration settings
   bool bCrc = pdi->bCrc;
@@ -665,10 +665,10 @@ bool nfc_target_init(const dev_info* pdi, byte* pbtRx, ui32* puiRxBits)
   return true;
 }
 
-bool nfc_target_receive_bits(const dev_info* pdi, byte* pbtRx, ui32* puiRxBits, byte* pbtRxPar)
+bool nfc_target_receive_bits(const dev_info* pdi, byte* pbtRx, uint32_t* puiRxBits, byte* pbtRxPar)
 {
-	ui32 uiFrameBits;
-  ui8 ui8Bits;
+	uint32_t uiFrameBits;
+  uint8_t ui8Bits;
 
 	// Try to gather a received frame from the reader
 	if (!pn53x_transceive(pdi,pncmd_target_receive,2)) return false;
@@ -695,7 +695,7 @@ bool nfc_target_receive_bits(const dev_info* pdi, byte* pbtRx, ui32* puiRxBits,
 	return true;
 }
 
-bool nfc_target_receive_bytes(const dev_info* pdi, byte* pbtRx, ui32* puiRxLen)
+bool nfc_target_receive_bytes(const dev_info* pdi, byte* pbtRx, uint32_t* puiRxLen)
 {
 	// Try to gather a received frame from the reader
 	if (!pn53x_transceive(pdi,pncmd_target_receive,2)) return false;
@@ -710,11 +710,11 @@ bool nfc_target_receive_bytes(const dev_info* pdi, byte* pbtRx, ui32* puiRxLen)
   return true;
 }
 
-bool nfc_target_send_bits(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxBits, const byte* pbtTxPar)
+bool nfc_target_send_bits(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxBits, const byte* pbtTxPar)
 {
-  ui32 uiFrameBits = 0;
-  ui32 uiFrameBytes = 0;
-  ui8 ui8Bits = 0;
+  uint32_t uiFrameBits = 0;
+  uint32_t uiFrameBytes = 0;
+  uint8_t ui8Bits = 0;
 
   // Check if we should prepare the parity bits ourself
   if (!pdi->bPar)
@@ -745,7 +745,7 @@ bool nfc_target_send_bits(const dev_info* pdi, const byte* pbtTx, const ui32 uiT
 }
 
 
-bool nfc_target_send_bytes(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxLen)
+bool nfc_target_send_bytes(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxLen)
 {
   // We can not just send bytes without parity if while the PN53X expects we handled them
   if (!pdi->bPar) return false;
diff --git a/src/libnfc.h b/src/libnfc.h
index f122137..04a50e9 100644
--- a/src/libnfc.h
+++ b/src/libnfc.h
@@ -21,6 +21,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #ifndef _LIBNFC_H_
 #define _LIBNFC_H_
 
+#include <stdint.h>
+
 #include "defines.h"
 #include "types.h"
 #include "bitutils.h"
@@ -31,17 +33,17 @@ void nfc_disconnect(dev_info* pdi);
 bool nfc_configure(dev_info* pdi, const dev_config_option dco, const bool bEnable);
 
 bool nfc_reader_init(const dev_info* pdi);
-bool nfc_reader_select(const dev_info* pdi, const init_modulation im, const byte* pbtInitData, const ui32 uiInitDataLen, tag_info* pti);
+bool nfc_reader_select(const dev_info* pdi, const init_modulation im, const byte* pbtInitData, const uint32_t uiInitDataLen, tag_info* pti);
 bool nfc_reader_deselect(const dev_info* pdi);
-bool nfc_reader_transceive_bits(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxBits, const byte* pbtTxPar, byte* pbtRx, ui32* puiRxBits, byte* pbtRxPar);
-bool nfc_reader_transceive_bytes(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxLen, byte* pbtRx, ui32* puiRxLen);
-bool nfc_reader_mifare_cmd(const dev_info* pdi, const mifare_cmd mc, const ui8 ui8Block, mifare_param* pmp);
+bool nfc_reader_transceive_bits(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxBits, const byte* pbtTxPar, byte* pbtRx, uint32_t* puiRxBits, byte* pbtRxPar);
+bool nfc_reader_transceive_bytes(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxLen, byte* pbtRx, uint32_t* puiRxLen);
+bool nfc_reader_mifare_cmd(const dev_info* pdi, const mifare_cmd mc, const uint8_t ui8Block, mifare_param* pmp);
 
-bool nfc_target_init(const dev_info* pdi, byte* pbtRx, ui32* puiRxBits);
-bool nfc_target_receive_bits(const dev_info* pdi, byte* pbtRx, ui32* puiRxBits, byte* pbtRxPar);
-bool nfc_target_receive_bytes(const dev_info* pdi, byte* pbtRx, ui32* puiRxLen);
-bool nfc_target_send_bits(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxBits, const byte* pbtTxPar);
-bool nfc_target_send_bytes(const dev_info* pdi, const byte* pbtTx, const ui32 uiTxLen);
+bool nfc_target_init(const dev_info* pdi, byte* pbtRx, uint32_t* puiRxBits);
+bool nfc_target_receive_bits(const dev_info* pdi, byte* pbtRx, uint32_t* puiRxBits, byte* pbtRxPar);
+bool nfc_target_receive_bytes(const dev_info* pdi, byte* pbtRx, uint32_t* puiRxLen);
+bool nfc_target_send_bits(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxBits, const byte* pbtTxPar);
+bool nfc_target_send_bytes(const dev_info* pdi, const byte* pbtTx, const uint32_t uiTxLen);
 
 #endif // _LIBNFC_H_
 
diff --git a/src/mftool.c b/src/mftool.c
index fb390d2..39c2229 100644
--- a/src/mftool.c
+++ b/src/mftool.c
@@ -20,6 +20,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <string.h>
 #include <ctype.h>
 
@@ -32,21 +33,21 @@ static mifare_param mp;
 static mifare_tag mtKeys;
 static mifare_tag mtDump;
 static bool bUseKeyA;
-static ui32 uiBlocks;
+static uint32_t uiBlocks;
 
-bool is_first_block(ui32 uiBlock)
+bool is_first_block(uint32_t uiBlock)
 {
   // Test if we are in the small or big sectors
   if (uiBlock < 128) return ((uiBlock)%4 == 0); else return ((uiBlock)%16 == 0);
 }
 
-bool is_trailer_block(ui32 uiBlock)
+bool is_trailer_block(uint32_t uiBlock)
 {
   // Test if we are in the small or big sectors
   if (uiBlock < 128) return ((uiBlock+1)%4 == 0); else return ((uiBlock+1)%16 == 0);
 }
 
-ui32 get_trailer_block(ui32 uiFirstBlock)
+uint32_t get_trailer_block(uint32_t uiFirstBlock)
 {
   // Test if we are in the small or big sectors
   if (uiFirstBlock<128) return uiFirstBlock+3; else return uiFirstBlock+15;
@@ -54,7 +55,7 @@ ui32 get_trailer_block(ui32 uiFirstBlock)
 
 bool read_card()
 {
-  i32 iBlock;
+  int32_t iBlock;
   mifare_cmd mc;
   bool bFailure = false;
 
@@ -136,8 +137,8 @@ bool read_card()
 
 bool write_card()
 {
-  ui32 uiBlock;
-  ui32 uiTrailerBlock;
+  uint32_t uiBlock;
+  uint32_t uiTrailerBlock;
   bool bFailure = false;
   mifare_cmd mc;
 
diff --git a/src/relay.c b/src/relay.c
index 65c1566..a942cc7 100644
--- a/src/relay.c
+++ b/src/relay.c
@@ -20,15 +20,17 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <stdint.h>
 #include <string.h>
+
 #include "libnfc.h"
 
 static byte abtReaderRx[MAX_FRAME_LEN];
 static byte abtReaderRxPar[MAX_FRAME_LEN];
-static ui32 uiReaderRxBits;
+static uint32_t uiReaderRxBits;
 static byte abtTagRx[MAX_FRAME_LEN];
 static byte abtTagRxPar[MAX_FRAME_LEN];
-static ui32 uiTagRxBits;
+static uint32_t uiTagRxBits;
 static dev_info* pdiReader;
 static dev_info* pdiTag;
 
diff --git a/src/types.h b/src/types.h
index ab3c02d..e0b1b28 100644
--- a/src/types.h
+++ b/src/types.h
@@ -21,6 +21,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #ifndef _LIBNFC_TYPES_H_
 #define _LIBNFC_TYPES_H_
 
+#include <stdint.h>
+
 #include "defines.h"
 
 // Compiler directive, set struct alignment to 1 byte for compatibility
@@ -47,13 +49,13 @@ typedef struct {
   bool bActive;                      // This represents if the PN53X device was initialized succesful
   bool bCrc;                         // Is the crc automaticly added, checked and removed from the frames
   bool bPar;                         // Does the PN53x chip handles parity bits, all parities are handled as data
-  ui8 ui8TxBits;                     // The last tx bits setting, we need to reset this if it does not apply anymore
+  uint8_t ui8TxBits;                     // The last tx bits setting, we need to reset this if it does not apply anymore
 } dev_info;
 
 struct dev_callbacks {
   const char* acDriver;              // Driver description
-  dev_info* (*connect)(const ui32 uiIndex);
-  bool (*transceive)(const dev_spec ds, const byte* pbtTx, const ui32 uiTxLen, byte* pbtRx, ui32* puiRxLen);
+  dev_info* (*connect)(const uint32_t uiIndex);
+  bool (*transceive)(const dev_spec ds, const byte* pbtTx, const uint32_t uiTxLen, byte* pbtRx, uint32_t* puiRxLen);
   void (*disconnect)(dev_info* pdi);
 };
 
@@ -81,14 +83,14 @@ typedef enum {
 typedef struct {
   byte abtAtqa[2];
   byte btSak;
-  ui32 uiUidLen;
+  uint32_t uiUidLen;
   byte abtUid[10];
-  ui32 uiAtsLen;
+  uint32_t uiAtsLen;
   byte abtAts[36];
 }tag_info_iso14443a;
 
 typedef struct {
-  ui32 uiLen;
+  uint32_t uiLen;
   byte btResCode;
   byte abtId[8];
   byte abtPad[8];
@@ -103,7 +105,7 @@ typedef struct {
   byte btParam3;
   byte btParam4;
   byte btCid;
-  ui32 uiInfLen;
+  uint32_t uiInfLen;
   byte abtInf[64];
 }tag_info_iso14443b;