changeset 4:095216e8453d

Hide register name abstraction in a separate file.
author darius@Inchoate
date Thu, 12 Mar 2009 16:30:47 +1030
parents 15d89caaf516
children 03eba20b5edb
files cons-reg.h cons.c
diffstat 2 files changed, 84 insertions(+), 56 deletions(-) [+]
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cons-reg.h	Thu Mar 12 16:30:47 2009 +1030
@@ -0,0 +1,71 @@
+/*
+ * Register abstraction for console code
+ *
+ * Copyright (c) 2008-2009
+ *      Daniel O'Connor <darius@dons.net.au>.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/* Decide what registers and ISRs to use */
+
+#ifdef UBRR0
+/* Dual UART devices (eg ATMega324p) */
+#define _SETBAUD(x) do { \
+	UBRR0 = UART_BAUD_SELECT(x, F_CPU);	\
+    } while(0)
+#define _INITREG() do {					\
+	UCSR0A = 0;					\
+	UCSR0B = _BV(RXEN0) | _BV(TXEN0) | _BV(RXCIE0);	\
+	UCSR0C = _BV(UCSZ01) | _BV(UCSZ00);		\
+    } while(0)
+#define _UCSRA UCSR0A
+#define _UDRE UDRE0
+#define _RXC RXC0
+#define _RXVECT USART0_RX_vect
+#define _TXVECT USART0_TX_vect
+#define _UDR UDR0
+#else
+#define _SETBAUD(x) do { \
+	UBRRH = UART_BAUD_SELECT(x, F_CPU) >> 8;	\
+	UBRRH = UART_BAUD_SELECT(x, F_CPU)  & 0xff;	\
+    } while(0)
+#define _INITREG() do {					\
+	UCSRA = 0;					\
+	UCSRB = _BV(RXEN) | _BV(TXEN) | _BV(RXCIE);	\
+	UCSRC = _BV(UCSZ1) | _BV(UCSZ0);		\
+    } while(0)
+#define _UCSRA UCSRA
+#define _UDRE UDRE
+#define _RXC RXC
+#define _UDR UDR
+
+/* Handle vector name inconsistencies */
+#ifdef USART_RXC_vect
+#define _RXVECT USART_RXC_vect
+#define _TXVECT USART_TXC_vect
+#else
+#define _RXVECT USART_RX_vect
+#define _TXVECT USART_TX_vect
+#endif
+#endif
+
--- a/cons.c	Wed Mar 11 17:28:39 2009 +1030
+++ b/cons.c	Thu Mar 12 16:30:47 2009 +1030
@@ -1,7 +1,7 @@
 /*
  * Console code for AVR board
  *
- * Copyright (c) 2008
+ * Copyright (c) 2008-2009
  *      Daniel O'Connor <darius@dons.net.au>.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -33,13 +33,10 @@
 #include <avr/interrupt.h>
 #include <avr/pgmspace.h>
 #include "cons.h"
+#include "cons-reg.h"
 
 #define UART_BAUD_SELECT(baudRate,xtalCpu) ((xtalCpu)/((baudRate)*16l)-1)
 
-#ifdef UBRR0
-#define DUALUART
-#endif
-
 /* Receive buffer storage */
 consbuf_t cmd;
 
@@ -64,36 +61,19 @@
 
 void
 cons_init(void) {
-#ifdef DUALUART
-    UBRR0 = UART_BAUD_SELECT(38400, F_CPU);
+    _SETBAUD(38400);
     
     /* Enable receiver and transmitter. Turn on rx interrupts */
-    UCSR0A = 0;
-    UCSR0B = _BV(RXEN0) | _BV(TXEN0) | _BV(RXCIE0);
-    UCSR0C = _BV(UCSZ01) | _BV(UCSZ00);
-#else
-    UBRRH = UART_BAUD_SELECT(38400, F_CPU) >> 8;
-    UBRRL = (uint8_t)UART_BAUD_SELECT(38400, F_CPU);
-
-    /* Enable receiver and transmitter. Turn on rx interrupts */
-    UCSRA = 0;
-    UCSRB = _BV(RXEN) | _BV(TXEN) | _BV(RXCIE);
-    UCSRC = _BV(URSEL) | _BV(UCSZ1) | _BV(UCSZ0);
-#endif
-
+    _INITREG();
+    
     fdevopen(_putc, NULL); /* Open stdout */
     fdevopen(NULL, _getc); /* Open stdin */
 }
 
 int
 cons_putc(char c) {
-#ifdef DUALUART
-    loop_until_bit_is_set(UCSR0A, UDRE0);
-    UDR0 = c;
-#else
-    loop_until_bit_is_set(UCSRA, UDRE);
-    UDR = c;
-#endif
+    loop_until_bit_is_set(_UCSRA, _UDRE);
+    _UDR = c;
 
     return(0);
 }
@@ -133,36 +113,17 @@
 
 char
 cons_getc(void) {
-#ifdef DUALUART
-    while (!(UCSR0A & _BV(RXC0)))
+    while (!(_UCSRA & _BV(_RXC)))
 	;
-    return (UDR0);
-#else
-    while (!(UCSRA & _BV(RXC)))
-	;
-    return (UDR);
-#endif
+    return (_UDR);
 }
 
 /* Rx complete */
-#ifdef DUALUART
-ISR(USART0_RX_vect) {
-#else
-ISR(USART_RXC_vect) {
-#endif
+ISR(_RXVECT) {
     char c;
 
-#ifdef DUALUART
-    while (UCSR0A & _BV(RXC0)) {
-#else
-    while (UCSRA & _BV(RXC)) {
-#endif
-
-#ifdef DUALUART
-	c = UDR0;
-#else
-	c = UDR;
-#endif
+    while (_UCSRA & _BV(_RXC)) {
+	c = _UDR;
 	/* 255 means we're waiting for main to process the command,
 	 * just throw stuff away
 	 */
@@ -207,10 +168,6 @@
 }
 
 /* Tx complete */
-#ifdef DUALUART
-ISR(USART0_TX_vect) {
-#else
-ISR(USART_TXC_vect) {
-#endif	
+ISR(_TXVECT) {
 }