2 * Copyright © 2009 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; version 2 of the License.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
20 __xdata struct ao_packet_recv ao_rx_packet;
21 __xdata struct ao_packet ao_tx_packet;
22 __pdata uint8_t ao_packet_rx_len, ao_packet_rx_used, ao_packet_tx_used;
24 static __xdata char tx_data[AO_PACKET_MAX];
25 static __xdata char rx_data[AO_PACKET_MAX];
26 static __pdata uint8_t rx_seq;
28 __xdata struct ao_task ao_packet_task;
29 __xdata uint8_t ao_packet_enable;
30 __xdata uint8_t ao_packet_master_sleeping;
36 ao_led_on(AO_LED_RED);
38 /* If any tx data is pending then copy it into the tx packet */
39 if (ao_packet_tx_used && ao_tx_packet.len == 0) {
40 ao_xmemcpy(&ao_tx_packet.d, tx_data, ao_packet_tx_used);
41 ao_tx_packet.len = ao_packet_tx_used;
43 ao_packet_tx_used = 0;
46 ao_radio_send(&ao_tx_packet, sizeof (ao_tx_packet));
48 ao_led_off(AO_LED_RED);
58 ao_led_on(AO_LED_GREEN);
60 dma_done = ao_radio_recv(&ao_rx_packet, sizeof (struct ao_packet_recv));
62 ao_led_off(AO_LED_GREEN);
65 /* Check to see if we got a valid packet */
68 if (!(ao_rx_packet.status & PKT_APPEND_STATUS_1_CRC_OK))
71 /* SYN packets carry no data */
72 if (ao_rx_packet.packet.len == AO_PACKET_SYN) {
73 rx_seq = ao_rx_packet.packet.seq;
74 ao_tx_packet.seq = ao_rx_packet.packet.ack;
75 ao_tx_packet.ack = rx_seq;
76 } else if (ao_rx_packet.packet.len) {
78 /* Check for incoming data at the next sequence and
79 * for an empty data buffer
81 if (ao_rx_packet.packet.seq == (uint8_t) (rx_seq + (uint8_t) 1) &&
82 ao_packet_rx_used == ao_packet_rx_len) {
84 /* Copy data to the receive data buffer and set up the
87 ao_xmemcpy(rx_data, ao_rx_packet.packet.d, ao_rx_packet.packet.len);
88 ao_packet_rx_used = 0;
89 ao_packet_rx_len = ao_rx_packet.packet.len;
91 /* Mark the sequence that we've received to
92 * let the sender know when we return a packet
94 rx_seq = ao_rx_packet.packet.seq;
95 ao_tx_packet.ack = rx_seq;
97 /* Poke anyone looking for received data */
98 ao_wakeup(&ao_stdin_ready);
102 /* If the other side has seen the latest data we queued,
103 * wake up any task waiting to send data and let them go again
105 if (ao_rx_packet.packet.ack == ao_tx_packet.seq) {
106 ao_tx_packet.len = 0;
107 ao_wakeup(&ao_tx_packet);
112 #ifndef PACKET_HAS_MASTER
113 #define PACKET_HAS_MASTER 1
116 #if PACKET_HAS_MASTER
118 ao_packet_flush(void)
120 /* If there is data to send, and this is the master,
121 * then poke the master to send all queued data
123 if (ao_packet_tx_used && ao_packet_master_sleeping)
124 ao_wakeup(&ao_packet_master_sleeping);
126 #endif /* PACKET_HAS_MASTER */
129 ao_packet_putchar(char c) __reentrant
131 while (ao_packet_tx_used == AO_PACKET_MAX && ao_packet_enable) {
132 #if PACKET_HAS_MASTER
138 if (ao_packet_enable)
139 tx_data[ao_packet_tx_used++] = c;
143 ao_packet_pollchar(void) __critical
145 if (!ao_packet_enable)
146 return AO_READ_AGAIN;
148 if (ao_packet_rx_used == ao_packet_rx_len)
149 return AO_READ_AGAIN;
151 return rx_data[ao_packet_rx_used++];