2 * Copyright © 2011 Keith Packard <keithp@keithp.com>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21 struct ao_fifo ao_serial1_rx_fifo;
22 struct ao_fifo ao_serial1_tx_fifo;
29 loop_until_bit_is_set(UCSR1A, UDRE1);
35 if (!ao_fifo_full(ao_serial1_rx_fifo))
36 ao_fifo_insert(ao_serial1_rx_fifo, UDR1);
37 ao_wakeup(&ao_serial1_rx_fifo);
38 #if USE_SERIAL_1_STDIN
39 ao_wakeup(&ao_stdin_ready);
43 static uint8_t ao_serial_tx1_started;
46 ao_serial1_tx_start(void)
48 if (!ao_fifo_empty(ao_serial1_tx_fifo) &&
49 !ao_serial_tx1_started)
51 ao_serial_tx1_started = 1;
52 ao_fifo_remove(ao_serial1_tx_fifo, UDR1);
58 ao_serial1_tx_started = 0;
59 ao_serial1_tx_start();
60 ao_wakeup(&ao_serial1_tx_fifo);
63 #if USE_SERIAL_1_STDIN
65 _ao_serial1_pollchar(void)
68 if (ao_fifo_empty(ao_serial1_rx_fifo)) {
72 ao_fifo_remove(ao_serial1_rx_fifo,c);
78 ao_serial1_getchar(void)
82 ao_arch_block_interrupts();
83 while (ao_fifo_empty(ao_serial1_rx_fifo))
84 ao_sleep(&ao_serial1_rx_fifo);
85 ao_fifo_remove(ao_serial1_rx_fifo, c);
86 ao_arch_release_interrupts();
91 ao_serial1_putchar(char c)
93 ao_arch_block_interrupts();
94 while (ao_fifo_full(ao_serial1_tx_fifo))
95 ao_sleep(&ao_serial1_tx_fifo);
96 ao_fifo_insert(ao_serial1_tx_fifo, c);
97 ao_serial_tx1_start();
98 ao_arch_release_interrupts();
102 ao_serial1_drain(void)
104 ao_arch_block_interrupts();
105 while (!ao_fifo_empty(ao_serial1_tx_fifo))
106 ao_sleep(&ao_serial1_tx_fifo);
107 ao_arch_release_interrupts();
110 static const struct {
112 } ao_serial_speeds[] = {
113 /* [AO_SERIAL_SPEED_4800] = */ {
114 F_CPU / (16UL * 4800UL) - 1
116 /* [AO_SERIAL_SPEED_9600] = */ {
117 F_CPU / (16UL * 9600UL) - 1
119 /* [AO_SERIAL_SPEED_19200] = */ {
120 F_CPU / (16UL * 19200UL) - 1
122 /* [AO_SERIAL_SPEED_57600] = */ {
123 F_CPU / (16UL * 57600UL) - 1
128 ao_serial1_set_speed(uint8_t speed)
131 if (speed > AO_SERIAL_SPEED_57600)
133 UBRR1L = ao_serial_speeds[speed].ubrr;
134 UBRR1H = ao_serial_speeds[speed].ubrr >> 8;
140 /* Ensure the uart is powered up */
142 PRR1 &= ~(1 << PRUSART1);
144 /* Pick a 9600 baud rate */
145 ao_serial_set_speed(AO_SERIAL_SPEED_9600);
148 UCSR1C = ((0 << UMSEL10) | /* Asynchronous mode */
149 (0 << UPM10) | /* No parity */
150 (0 << USBS1) | /* 1 stop bit */
151 (3 << UCSZ10) | /* 8 bit characters */
152 (0 << UCPOL1)); /* MBZ for async mode */
153 UCSR1B = ((1 << RXEN1) | /* Enable receiver */
154 (1 << TXEN1) | /* Enable transmitter */
155 (1 << RXCIE1) | /* Enable receive interrupts */
156 (1 << UDRIE1)); /* Enable transmit empty interrupts */
157 #if USE_SERIAL_1_STDIN
158 ao_add_stdio(_ao_serial1_pollchar,