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;
35 ao_led_on(AO_LED_RED);
36 /* If any tx data is pending then copy it into the tx packet */
37 if (ao_packet_tx_used && ao_tx_packet.len == 0) {
38 ao_xmemcpy(&ao_tx_packet.d, tx_data, ao_packet_tx_used);
39 ao_tx_packet.len = ao_packet_tx_used;
41 ao_packet_tx_used = 0;
44 ao_radio_send(&ao_tx_packet, sizeof (ao_tx_packet));
45 ao_led_off(AO_LED_RED);
54 ao_led_on(AO_LED_GREEN);
56 dma_done = ao_radio_recv(&ao_rx_packet, sizeof (struct ao_packet_recv));
58 ao_led_off(AO_LED_GREEN);
61 /* Check to see if we got a valid packet */
64 if (!(ao_rx_packet.status & PKT_APPEND_STATUS_1_CRC_OK))
67 /* SYN packets carry no data */
68 if (ao_rx_packet.packet.len == AO_PACKET_SYN) {
69 rx_seq = ao_rx_packet.packet.seq;
70 ao_tx_packet.seq = ao_rx_packet.packet.ack;
71 ao_tx_packet.ack = rx_seq;
72 } else if (ao_rx_packet.packet.len) {
74 /* Check for incoming data at the next sequence and
75 * for an empty data buffer
77 if (ao_rx_packet.packet.seq == (uint8_t) (rx_seq + (uint8_t) 1) &&
78 ao_packet_rx_used == ao_packet_rx_len) {
80 /* Copy data to the receive data buffer and set up the
83 ao_xmemcpy(rx_data, ao_rx_packet.packet.d, ao_rx_packet.packet.len);
84 ao_packet_rx_used = 0;
85 ao_packet_rx_len = ao_rx_packet.packet.len;
87 /* Mark the sequence that we've received to
88 * let the sender know when we return a packet
90 rx_seq = ao_rx_packet.packet.seq;
91 ao_tx_packet.ack = rx_seq;
93 /* Poke anyone looking for received data */
94 ao_wakeup(&ao_stdin_ready);
98 /* If the other side has seen the latest data we queued,
99 * wake up any task waiting to send data and let them go again
101 if (ao_rx_packet.packet.ack == ao_tx_packet.seq) {
102 ao_tx_packet.len = 0;
103 ao_wakeup(&ao_tx_packet);
108 #ifndef PACKET_HAS_MASTER
109 #define PACKET_HAS_MASTER 1
112 #if PACKET_HAS_MASTER
114 ao_packet_flush(void)
116 /* If there is data to send, and this is the master,
117 * then poke the master to send all queued data
119 if (ao_packet_tx_used && ao_packet_master_sleeping)
120 ao_wakeup(&ao_packet_master_sleeping);
122 #endif /* PACKET_HAS_MASTER */
125 ao_packet_putchar(char c) __reentrant
127 while (ao_packet_tx_used == AO_PACKET_MAX && ao_packet_enable) {
128 #if PACKET_HAS_MASTER
134 if (ao_packet_enable)
135 tx_data[ao_packet_tx_used++] = c;
139 ao_packet_pollchar(void) __critical
141 if (!ao_packet_enable)
142 return AO_READ_AGAIN;
144 if (ao_packet_rx_used == ao_packet_rx_len)
145 return AO_READ_AGAIN;
147 return rx_data[ao_packet_rx_used++];