Replace usart initialization parameters with configuration

Baudrate and other configurations are now defined in compile time by
preprocessor flags. This simplifies output code.

5 files changed, 104 insertions, 139 deletions

diff --git a/examples/usartecho/echo.c b/examples/usartecho/echo.c
index 4ba9364..12b88f6 100644
--- a/examples/usartecho/echo.c
+++ b/examples/usartecho/echo.c
@@ -4,16 +4,19 @@
 #include "../../usart.h"
 
 void rec(uint8_t data) {
-    if (data)
+    if (data == '\r') {
+        usart_send_str("\n\r"); // Send new line character with carriage return
+    } else if (data)
         usart_send(data);
 }
 
 int main() {
-    usart_init_uart();
+    DDRB = _BV(DDB1);
+    usart_init_async();
     SREG |= _BV(7);
     usart_send('a');
     usart_send('b');
-    usart_send('c');
+    usart_send('c'); // This character is not printed for some reason TODO
     usart_send('d');
     usart_send_str("\n\rHello, there is UART echo!\n\r");
     usart_receive = rec;
diff --git a/examples/usartecho/makefile b/examples/usartecho/makefile
index 7475127..48a713c 100644
--- a/examples/usartecho/makefile
+++ b/examples/usartecho/makefile
@@ -5,10 +5,14 @@ F_CPU = 16000000L
 IOE_PREFIX = ../..
 IOE_CFLAGS = -Os -ffunction-sections -fdata-sections -fshort-enums -Wall \
 			 -DCONFIG_IOE_USART_OUTBUFFER_SIZE=64 \
-			 -DCONFIG_IOE_USART_OUTBUFFER_MODE=0
+			 -DCONFIG_IOE_USART_OUTBUFFER_MODE=0 \
+			 -DCONFIG_IOE_USART_BAUD=115200 \
+			 -DCONFIG_IOE_USART_PARITY=USART_PARITY_NONE \
+			 -DCONFIG_IOE_USART_STOPBIT=USART_STOPBIT_SINGLE \
+			 -DCONFIG_IOE_USART_DATABITS=8
 
 all: usart.hex
-	@echo Flash usart.hex to chip
+	@echo Now you can flash usart.hex to your chip.
 
 clean: ioeclean
 	$(RM) echo.o
diff --git a/src/usart.c b/src/usart.c
index 745d75c..dca5878 100644
--- a/src/usart.c
+++ b/src/usart.c
@@ -2,83 +2,98 @@
 
 #ifdef MCUSUPPORT_USART
 
-volatile int8_t _usart_busy;
+#define USART_PARITY_NONE 0
+#define USART_PARITY_ODD 1
+#define USART_PARITY_EVEN 2
+
+#define USART_STOPBIT_SINGLE 1
+#define USART_STOPBIT_DOUBLE 2
+
+#ifndef CONFIG_IOE_USART_BAUD
+#warning "CONFIG_IOE_USART_BAUNDRATE not defined. Setting default 9600."
+#define CONFIG_IOE_USART_BAUD 9600
+#endif
+#ifndef CONFIG_IOE_USART_PARITY
+#warning "CONFIG_IOE_USART_PARITY not defined. Using default USART_PARITY_NONE."
+#define CONFIG_IOE_USART_PARITY USART_PARITY_NONE
+#endif
+#ifndef CONFIG_IOE_USART_STOPBIT
+#warning "CONFIG_IOE_USART_STOPBIT not defined. Using default USART_STOPBIT_SINGLE."
+#define CONFIG_IOE_USART_STOPBIT USART_STOPBIT_SINGLE
+#endif
+#ifndef CONFIG_IOE_USART_DATABITS
+#warning "CONFIG_IOE_USART_DATABITS not defined. Using default 8."
+#define CONFIG_IOE_USART_DATABITS 8
+#endif
+
+#if !((CONFIG_IOE_USART_PARITY == USART_PARITY_NONE) || \
+      (CONFIG_IOE_USART_PARITY == USART_PARITY_ODD) || \
+      (CONFIG_IOE_USART_PARITY == USART_PARITY_EVEN))
+#error "CONFIG_IOE_USART_PARITY has value, that is not allowed."
+#endif
+
+#if !((CONFIG_IOE_USART_STOPBIT == USART_STOPBIT_SINGLE) || \
+      (CONFIG_IOE_USART_STOPBIT == USART_STOPBIT_DOUBLE))
+#error "CONFIG_IOE_USART_STOPBIT has value, that is not allowed."
+#endif
+
+#if !((CONFIG_IOE_USART_DATABITS == 5) || \
+      (CONFIG_IOE_USART_DATABITS == 6) || \
+      (CONFIG_IOE_USART_DATABITS == 7) || \
+      (CONFIG_IOE_USART_DATABITS == 8))
+// TODO DATABITS 9 is not supported
+#error "CONFIG_IOE_USART_DATABITS has value, that is not allowed."
+#endif
+
+#if (defined CONFIG_IOE_USART_INFILE) && (CONFIG_IOE_USART_INBUFFER_SIZE <= 0)
+#error "USART Input file can't be enabled without input buffer"
+#endif
+#if (defined CONFIG_IOE_USART_OUTFILE) && (CONFIG_IOE_USART_OUTBUFFER_SIZE <= 0)
+#error "USART Input file can't be enabled without output buffer"
+#endif
 
-inline void usart_init_uart(void) {
-    usart_init_async(USART_BAUDRATE_115200, USART_PARITY_NONE,
-                     USART_STOPBIT_SINGLE, USART_DATABITS_8);
-}
 
-void usart_init_async(enum usartBaudrate baudrate,
-                      enum usartParity parity, enum usartStopBit stopbit,
-                      enum usartDataBits databits) {
+volatile int8_t _usart_busy;
+
+void usart_init_async(void) {
     _usart_busy = 0;
-    switch (baudrate) {
-    case USART_BAUDRATE_2400:
-#define BAUD 2400
-#include "usart_baundrate_helper.h"
-        break;
-    case USART_BAUDRATE_4800:
-#define BAUD 4800
-#include "usart_baundrate_helper.h"
-        break;
-    case USART_BAUDRATE_9600:
-#define BAUD 9600
-#include "usart_baundrate_helper.h"
-        break;
-    case USART_BAUDRATE_19200:
-#define BAUD 19200
-#include "usart_baundrate_helper.h"
-        break;
-    case USART_BAUDRATE_38400:
-#define BAUD 38400
-#include "usart_baundrate_helper.h"
-        break;
-    case USART_BAUDRATE_57600:
-#define BAUD 57600
-#include "usart_baundrate_helper.h"
-        break;
-    case USART_BAUDRATE_115200:
-#define BAUD 115200
-#include "usart_baundrate_helper.h"
-        break;
-    }
-    switch (parity) {
-    case USART_PARITY_NONE:
-        UCSR0C &= ~(_BV(UPM00) | _BV(UPM01));
-        break;
-    case USART_PARITY_ODD:
-        UCSR0C &= ~_BV(UPM00);
-        UCSR0C |= _BV(UPM01);
-        break;
-    case USART_PARITY_EVEN:
-        UCSR0C |= _BV(UPM00) | _BV(UPM01);
-        break;
-    }
-    switch (stopbit) {
-    case USART_STOPBIT_SINGLE:
-        UCSR0C &= ~_BV(USBS0);
-        break;
-    case USART_STOPBIT_DOUBLE:
-        UCSR0C |= _BV(USBS0);
-        break;
-    }
-    switch (databits) {
-    case USART_DATABITS_5:
-        UCSR0C &= ~(_BV(UCSZ00) | _BV(UCSZ01));
-        break;
-    case USART_DATABITS_6:
-        UCSR0C &= ~_BV(UCSZ01);
-        UCSR0C |= _BV(UCSZ00);
-        break;
-    case USART_DATABITS_7:
-        UCSR0C &= ~_BV(UCSZ00);
-        UCSR0C |= _BV(UCSZ01);
-        break;
-    case USART_DATABITS_8:
-        UCSR0C |= _BV(UCSZ00) | _BV(UCSZ01);
-        break;
-    }
+#define BAUD CONFIG_IOE_USART_BAUD
+#include <util/setbaud.h>
+    UBRR0H = UBRRH_VALUE;
+    UBRR0L = UBRRL_VALUE;
+#if USE_2X
+    UCSR0A |= _BV(U2X0);
+#else
+    UCSR0A &= ~_BV(U2X0);
+#endif
+
+#if CONFIG_IOE_USART_PARITY == USART_PARITY_NONE
+    UCSR0C &= ~(_BV(UPM00) | _BV(UPM01));
+#elif CONFIG_IOE_USART_PARITY == USART_PARITY_ODD
+    UCSR0C &= ~_BV(UPM00);
+    UCSR0C |= _BV(UPM01);
+#else // USART_PARITY_EVEN
+    UCSR0C |= _BV(UPM00) | _BV(UPM01);
+#endif
+
+#if CONFIG_IOE_USART_STOPBIT == USART_STOPBIT_SINGLE
+    UCSR0C &= ~_BV(USBS0);
+#else
+    UCSR0C |= _BV(USBS0);
+#endif
+
+#if CONFIG_IOE_USART_DATABITS == 5
+    UCSR0C &= ~(_BV(UCSZ00) | _BV(UCSZ01));
+#elif CONFIG_IOE_USART_DATABITS == 6
+    UCSR0C &= ~_BV(UCSZ01);
+    UCSR0C |= _BV(UCSZ00);
+#elif CONFIG_IOE_USART_DATABITS == 7
+    UCSR0C &= ~_BV(UCSZ00);
+    UCSR0C |= _BV(UCSZ01);
+#elif CONFIG_IOE_USART_DATABITS == 8
+    UCSR0C |= _BV(UCSZ00) | _BV(UCSZ01);
+#endif
+
     // Enable receiver, transmitter and RX complete,
     // Data register empty interrupts
     UCSR0B = _BV(RXEN0) | _BV(TXEN0) | _BV(RXCIE0) | _BV(UDRIE0);
diff --git a/src/usart_baundrate_helper.h b/src/usart_baundrate_helper.h
deleted file mode 100644
index 0271bdd..0000000
--- a/src/usart_baundrate_helper.h
+++ /dev/null
@@ -1,12 +0,0 @@
-#include <util/setbaud.h>
-UBRR0H = UBRRH_VALUE;
-UBRR0L = UBRRL_VALUE;
-#if USE_2X
-UCSR0A |= _BV(U2X0);
-#else
-UCSR0A &= ~_BV(U2X0);
-#endif
-#undef BAUD
-#undef UBRRH_VALUE
-#undef UBRRL_VALUE
-#undef USE_2X
diff --git a/usart.h b/usart.h
index 04ed963..8ff0773 100644
--- a/usart.h
+++ b/usart.h
@@ -13,52 +13,12 @@
 #error "No USART interface is known on your mcu."
 #endif
 
-enum usartBaudrate {
-    USART_BAUDRATE_2400,
-    USART_BAUDRATE_4800,
-    USART_BAUDRATE_9600,
-    USART_BAUDRATE_19200,
-    USART_BAUDRATE_38400,
-    USART_BAUDRATE_57600,
-    USART_BAUDRATE_115200
-};
-
-enum usartParity {
-    USART_PARITY_NONE,
-    USART_PARITY_ODD,
-    USART_PARITY_EVEN
-};
-
-enum usartStopBit {
-    USART_STOPBIT_SINGLE = 1,
-    USART_STOPBIT_DOUBLE = 2
-};
-
-enum usartDataBits {
-    USART_DATABITS_5 = 5,
-    USART_DATABITS_6 = 6,
-    USART_DATABITS_7 = 7,
-    USART_DATABITS_8 = 8,
-    // USART_DATABITS_9 = 9 // Not supported yet
-};
-
-// Not supported yet. This is for synchronous mode only
-//enum usartClockPolarity {
-    //USART_CLOCKPOLARITY_FALLING,
-    //USART_CLOCKPOLARITY_RISING
-//};
+// TODO clock polarity and synchronous mode
 
 #define USART_FRAMEERROR  _BV(FE0)
 #define USART_DATAOVERRUN _BV(DOR0)
 #define USART_PARITYERROR _BV(UPE0)
 
-#if (defined CONFIG_IOE_USART_INFILE) && (CONFIG_IOE_USART_INBUFFER_SIZE <= 0)
-#error "USART Input file can't be enabled without input buffer"
-#endif
-#if (defined CONFIG_IOE_USART_OUTFILE) && (CONFIG_IOE_USART_OUTBUFFER_SIZE <= 0)
-#error "USART Input file can't be enabled without output buffer"
-#endif
-
 #if CONFIG_IOE_USART_INBUFFER_SIZE > 0
 #define _IOE_USART_INBUFFER
 volatile IOEBUFFER(_ioe_usart_inbuffer, CONFIG_IOE_USART_INBUFFER_SIZE);
@@ -70,14 +30,9 @@ volatile IOEBUFFER(_ioe_usart_outbuffer, CONFIG_IOE_USART_OUTBUFFER_SIZE);
 
 
 /*
- * Initialize USART device with 115200 baud rate, no parity, single stop bit,
- * and 8 data bits.
- * This function serves as fast default initialization.
+ * Initialize USART device.
  */
-void usart_init_uart(void);
-void usart_init_async(enum usartBaudrate,
-                      enum usartParity, enum usartStopBit,
-                      enum usartDataBits);
+void usart_init_async(void);
 void usart_send(uint8_t data);
 #ifdef _IOE_USART_OUTBUFFER
 void usart_send_str(char *str);