o add ff lib

o add ff lib samples
o add ff linux sample

tools/ffsample/avr/uart.c

@@ -0,0 +1,128 @@
+/*------------------------------------------------*/
+/* UART functions                                 */
+
+
+#include <avr/io.h>
+#include <avr/interrupt.h>
+#include "uart.h"
+
+#define	SYSCLK		9216000
+#define	BAUD		115200
+
+
+typedef struct _fifo {
+	uint8_t	idx_w;
+	uint8_t	idx_r;
+	uint8_t	count;
+	uint8_t buff[64];
+} FIFO;
+
+
+static volatile
+FIFO txfifo, rxfifo;
+
+
+
+/* Initialize UART */
+
+void uart_init()
+{
+	rxfifo.idx_r = 0;
+	rxfifo.idx_w = 0;
+	rxfifo.count = 0;
+	txfifo.idx_r = 0;
+	txfifo.idx_w = 0;
+	txfifo.count = 0;
+
+	UBRR0L = SYSCLK/BAUD/16-1;
+	UCSR0B = _BV(RXEN0)|_BV(RXCIE0)|_BV(TXEN0);
+}
+
+
+/* Get a received character */
+
+uint8_t uart_test ()
+{
+	return rxfifo.count;
+}
+
+
+uint8_t uart_get ()
+{
+	uint8_t d, i;
+
+
+	i = rxfifo.idx_r;
+	while(rxfifo.count == 0);
+	d = rxfifo.buff[i++];
+	cli();
+	rxfifo.count--;
+	sei();
+	if(i >= sizeof(rxfifo.buff))
+		i = 0;
+	rxfifo.idx_r = i;
+
+	return d;
+}
+
+
+/* Put a character to transmit */
+
+void uart_put (uint8_t d)
+{
+	uint8_t i;
+
+
+	i = txfifo.idx_w;
+	while(txfifo.count >= sizeof(txfifo.buff));
+	txfifo.buff[i++] = d;
+	cli();
+	txfifo.count++;
+	UCSR0B = _BV(RXEN0)|_BV(RXCIE0)|_BV(TXEN0)|_BV(UDRIE0);
+	sei();
+	if(i >= sizeof(txfifo.buff))
+		i = 0;
+	txfifo.idx_w = i;
+}
+
+
+/* UART RXC interrupt */
+
+SIGNAL(SIG_UART0_RECV)
+{
+	uint8_t d, n, i;
+
+
+	d = UDR0;
+	n = rxfifo.count;
+	if(n < sizeof(rxfifo.buff)) {
+		rxfifo.count = ++n;
+		i = rxfifo.idx_w;
+		rxfifo.buff[i++] = d;
+		if(i >= sizeof(rxfifo.buff))
+			i = 0;
+		rxfifo.idx_w = i;
+	}
+}
+
+
+/* UART UDRE interrupt */
+
+SIGNAL(SIG_UART0_DATA)
+{
+	uint8_t n, i;
+
+
+	n = txfifo.count;
+	if(n) {
+		txfifo.count = --n;
+		i = txfifo.idx_r;
+		UDR0 = txfifo.buff[i++];
+		if(i >= sizeof(txfifo.buff))
+			i = 0;
+		txfifo.idx_r = i;
+	}
+	if(n == 0)
+		UCSR0B = _BV(RXEN0)|_BV(RXCIE0)|_BV(TXEN0);
+}
+