altos: get avr-demo to build. Pull in AVR drivers and LCD driver

[fw/altos] / src / avr / ao_serial_avr.c

diff --git a/src/avr/ao_serial_avr.c b/src/avr/ao_serial_avr.c
new file mode 100644 (file)
index 0000000..2fe3975
--- /dev/null
+++ b/src/avr/ao_serial_avr.c
@@ -0,0 +1,166 @@
+/*
+ * Copyright © 2011 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+#include "ao.h"
+
+__xdata struct ao_fifo ao_usart1_rx_fifo;
+__xdata struct ao_fifo ao_usart1_tx_fifo;
+
+void
+ao_debug_out(char c)
+{
+       if (c == '\n')
+               ao_debug_out('\r');
+       loop_until_bit_is_set(UCSR1A, UDRE1);
+       UDR1 = c;
+}
+
+ISR(USART1_RX_vect)
+{
+       if (!ao_fifo_full(ao_usart1_rx_fifo))
+               ao_fifo_insert(ao_usart1_rx_fifo, UDR1);
+       ao_wakeup(&ao_usart1_rx_fifo);
+#if USE_SERIAL_STDIN
+       ao_wakeup(&ao_stdin_ready);
+#endif
+}
+
+static __xdata uint8_t ao_serial_tx1_started;
+
+static void
+ao_serial_tx1_start(void)
+{
+       if (!ao_fifo_empty(ao_usart1_tx_fifo) &&
+           !ao_serial_tx1_started)
+       {
+               ao_serial_tx1_started = 1;
+               ao_fifo_remove(ao_usart1_tx_fifo, UDR1);
+       }
+}
+
+ISR(USART1_UDRE_vect)
+{
+       ao_serial_tx1_started = 0;
+       ao_serial_tx1_start();
+       ao_wakeup(&ao_usart1_tx_fifo);
+}
+
+char
+ao_serial_getchar(void) __critical
+{
+       char    c;
+       cli();
+       while (ao_fifo_empty(ao_usart1_rx_fifo))
+               ao_sleep(&ao_usart1_rx_fifo);
+       ao_fifo_remove(ao_usart1_rx_fifo, c);
+       sei();
+       return c;
+}
+
+#if USE_SERIAL_STDIN
+char
+ao_serial_pollchar(void) __critical
+{
+       char    c;
+       cli();
+       if (ao_fifo_empty(ao_usart1_rx_fifo)) {
+               sei();
+               return AO_READ_AGAIN;
+       }
+       ao_fifo_remove(ao_usart1_rx_fifo,c);
+       sei();
+       return c;
+}
+#endif
+
+void
+ao_serial_putchar(char c) __critical
+{
+       cli();
+       while (ao_fifo_full(ao_usart1_tx_fifo))
+               ao_sleep(&ao_usart1_tx_fifo);
+       ao_fifo_insert(ao_usart1_tx_fifo, c);
+       ao_serial_tx1_start();
+       sei();
+}
+
+void
+ao_serial_drain(void) __critical
+{
+       cli();
+       while (!ao_fifo_empty(ao_usart1_tx_fifo))
+               ao_sleep(&ao_usart1_tx_fifo);
+       sei();
+}
+
+static const struct {
+       uint16_t ubrr;
+} ao_serial_speeds[] = {
+       /* [AO_SERIAL_SPEED_4800] = */ {
+               F_CPU / (16UL * 4800UL) - 1
+       },
+       /* [AO_SERIAL_SPEED_9600] = */ {
+               F_CPU / (16UL * 9600UL) - 1
+       },
+       /* [AO_SERIAL_SPEED_19200] = */ {
+               F_CPU / (16UL * 19200UL) - 1
+       },
+       /* [AO_SERIAL_SPEED_57600] = */ {
+               F_CPU / (16UL * 57600UL) - 1
+       },
+};
+
+void
+ao_serial_set_speed(uint8_t speed)
+{
+       ao_serial_drain();
+       if (speed > AO_SERIAL_SPEED_57600)
+               return;
+       UBRR1L = ao_serial_speeds[speed].ubrr;
+       UBRR1H = ao_serial_speeds[speed].ubrr >> 8;
+}
+
+void
+ao_serial_init(void)
+{
+       /* Ensure the uart is powered up */
+
+       PRR1 &= ~(1 << PRUSART1);
+
+       /* Pick a 9600 baud rate */
+       ao_serial_set_speed(AO_SERIAL_SPEED_9600);
+
+       UCSR1A = 0;
+       UCSR1C = ((0 << UMSEL10) |      /* Asynchronous mode */
+                 (0 << UPM10) |        /* No parity */
+                 (0 << USBS1) |        /* 1 stop bit */
+                 (3 << UCSZ10) |       /* 8 bit characters */
+                 (0 << UCPOL1));       /* MBZ for async mode */
+       UCSR1B = ((1 << RXEN1) |        /* Enable receiver */
+                 (1 << TXEN1) |        /* Enable transmitter */
+                 (1 << RXCIE1) |       /* Enable receive interrupts */
+                 (1 << UDRIE1));       /* Enable transmit empty interrupts */
+#if 0
+#if USE_SERIAL_STDIN
+       int8_t  i;
+       i = ao_add_stdio(ao_serial_pollchar,
+                        ao_serial_putchar,
+                        NULL);
+       printf("Register serial stdio as %d\n", i);
+#endif
+#endif
+}