diff options
Diffstat (limited to 'src/drivers/ao_packet.c')
| -rw-r--r-- | src/drivers/ao_packet.c | 176 | 
1 files changed, 176 insertions, 0 deletions
| diff --git a/src/drivers/ao_packet.c b/src/drivers/ao_packet.c new file mode 100644 index 00000000..d813b25f --- /dev/null +++ b/src/drivers/ao_packet.c @@ -0,0 +1,176 @@ +/* + * Copyright © 2009 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_packet_recv ao_rx_packet; +__xdata struct ao_packet ao_tx_packet; +__pdata uint8_t ao_packet_rx_len, ao_packet_rx_used, ao_packet_tx_used; + +static __xdata char tx_data[AO_PACKET_MAX]; +static __xdata char rx_data[AO_PACKET_MAX]; +static __pdata uint8_t rx_seq; + +__xdata struct ao_task	ao_packet_task; +__xdata uint8_t ao_packet_enable; + +#if PACKET_HAS_MASTER +__xdata uint8_t ao_packet_master_sleeping; +__xdata uint8_t ao_packet_last_rssi; +#endif + +void +ao_packet_send(void) +{ +#ifdef AO_LED_RED +	ao_led_on(AO_LED_RED); +#endif +	/* If any tx data is pending then copy it into the tx packet */ +	if (ao_packet_tx_used && ao_tx_packet.len == 0) { +		ao_xmemcpy(&ao_tx_packet.d, tx_data, ao_packet_tx_used); +		ao_tx_packet.len = ao_packet_tx_used; +		ao_tx_packet.seq++; +		ao_packet_tx_used = 0; +		ao_wakeup(&tx_data); +	} +	ao_radio_send(&ao_tx_packet, sizeof (ao_tx_packet)); +#ifdef AO_LED_RED +	ao_led_off(AO_LED_RED); +#endif +} + +uint8_t +ao_packet_recv(void) +{ +	uint8_t	dma_done; + +#ifdef AO_LED_GREEN +	ao_led_on(AO_LED_GREEN); +#endif +	dma_done = ao_radio_recv(&ao_rx_packet, sizeof (struct ao_packet_recv)); +#ifdef AO_LED_GREEN +	ao_led_off(AO_LED_GREEN); +#endif +#if AO_PROFILE +		{ +			extern uint32_t	ao_rx_start_tick, ao_rx_packet_tick, ao_rx_done_tick, ao_rx_last_done_tick; +			extern uint32_t ao_fec_decode_start, ao_fec_decode_end; + +			printf ("between packet: %d\n", ao_rx_start_tick - ao_rx_last_done_tick); +			printf ("receive start delay: %d\n", ao_rx_packet_tick - ao_rx_start_tick); +			printf ("decode time: %d\n", ao_fec_decode_end - ao_fec_decode_start); +			printf ("rx cleanup: %d\n\n", ao_rx_done_tick - ao_fec_decode_end); +			flush(); +		} +#endif + +	/* Check to see if we got a valid packet */ +	if (!dma_done) +		return 0; +	if (!(ao_rx_packet.status & AO_RADIO_STATUS_CRC_OK)) +		return 0; + +#if PACKET_HAS_MASTER +	ao_packet_last_rssi = ao_rx_packet.rssi; +#endif +	/* Accept packets with matching call signs, or any packet if +	 * our callsign hasn't been configured +	 */ +	if (ao_xmemcmp(ao_rx_packet.packet.callsign, +		       ao_config.callsign, +		       AO_MAX_CALLSIGN) != 0 && +	    ao_xmemcmp(ao_config.callsign, CODE_TO_XDATA("N0CALL"), 7) != 0) +		return 0; + +	/* SYN packets carry no data */ +	if (ao_rx_packet.packet.len == AO_PACKET_SYN) { +		rx_seq = ao_rx_packet.packet.seq; +		ao_tx_packet.seq = ao_rx_packet.packet.ack; +		ao_tx_packet.ack = rx_seq; +	} else if (ao_rx_packet.packet.len) { + +		/* Check for incoming data at the next sequence and +		 * for an empty data buffer +		 */ +		if (ao_rx_packet.packet.seq == (uint8_t) (rx_seq + (uint8_t) 1) && +		    ao_packet_rx_used == ao_packet_rx_len) { + +			/* Copy data to the receive data buffer and set up the +			 * offsets +			 */ +			ao_xmemcpy(rx_data, ao_rx_packet.packet.d, ao_rx_packet.packet.len); +			ao_packet_rx_used = 0; +			ao_packet_rx_len = ao_rx_packet.packet.len; + +			/* Mark the sequence that we've received to +			 * let the sender know when we return a packet +			 */ +			rx_seq = ao_rx_packet.packet.seq; +			ao_tx_packet.ack = rx_seq; + +			/* Poke anyone looking for received data */ +			ao_wakeup(&ao_stdin_ready); +		} +	} + +	/* If the other side has seen the latest data we queued, +	 * wake up any task waiting to send data and let them go again +	 */ +	if (ao_rx_packet.packet.ack == ao_tx_packet.seq) { +		ao_tx_packet.len = 0; +		ao_wakeup(&ao_tx_packet); +	} +	return 1; +} + +#if PACKET_HAS_MASTER +void +ao_packet_flush(void) +{ +	/* If there is data to send, and this is the master, +	 * then poke the master to send all queued data +	 */ +	if (ao_packet_tx_used && ao_packet_master_sleeping) +		ao_wakeup(&ao_packet_master_sleeping); +} +#endif /* PACKET_HAS_MASTER */ + +void +ao_packet_putchar(char c) __reentrant +{ +	while (ao_packet_tx_used == AO_PACKET_MAX && ao_packet_enable) { +#if PACKET_HAS_MASTER +		ao_packet_flush(); +#endif +		ao_sleep(&tx_data); +	} + +	if (ao_packet_enable) +		tx_data[ao_packet_tx_used++] = c; +} + +char +ao_packet_pollchar(void) __critical +{ +	if (!ao_packet_enable) +		return AO_READ_AGAIN; + +	if (ao_packet_rx_used == ao_packet_rx_len) +		return AO_READ_AGAIN; + +	return rx_data[ao_packet_rx_used++]; +} | 
