diff options
Diffstat (limited to 'apps/px4io/comms.c')
-rw-r--r-- | apps/px4io/comms.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/apps/px4io/comms.c b/apps/px4io/comms.c new file mode 100644 index 000000000..19802bf4f --- /dev/null +++ b/apps/px4io/comms.c @@ -0,0 +1,136 @@ +/**************************************************************************** + * + * Copyright (C) 2012 PX4 Development Team. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name PX4 nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/** + * @file FMU communication for the PX4IO module. + */ + + +#include <nuttx/config.h> +#include <stdio.h> +#include <stdbool.h> +#include <fcntl.h> +#include <unistd.h> +#include <debug.h> +#include <stdlib.h> +#include <errno.h> +#include <string.h> + +#include <nuttx/clock.h> + +#include <arch/board/up_hrt.h> +#include <systemlib/hx_stream.h> +#include <systemlib/perf_counter.h> + +#include "px4io.h" + +#define FMU_MIN_REPORT_INTERVAL 5000 /* 5ms */ +#define FMU_MAX_REPORT_INTERVAL 100000 /* 100ms */ + +static int fmu_fd; +static hx_stream_t stream; + +static struct px4io_report report; + +static void comms_handle_frame(void *arg, const void *buffer, size_t length); + +void +comms_init(void) +{ + fmu_fd = open("/dev/ttyS1", O_RDWR | O_NONBLOCK); + if (fmu_fd < 0) + lib_lowprintf("COMMS: fmu open failed %d\n", errno); + + stream = hx_stream_init(fmu_fd, comms_handle_frame, NULL); + + report.i2f_magic = I2F_MAGIC; +} + +void +comms_check(void) +{ + static hrt_abstime last_report_time; + hrt_abstime now, delta; + uint8_t c; + + /* should we send a report to the FMU? */ + now = hrt_absolute_time(); + delta = now - last_report_time; + if ((delta > FMU_MIN_REPORT_INTERVAL) && + (system_state.fmu_report_due || (delta > FMU_MAX_REPORT_INTERVAL))) { + + system_state.fmu_report_due = false; + last_report_time = now; + + /* populate the report */ + for (unsigned i = 0; i < system_state.rc_channels; i++) + report.rc_channel[i] = system_state.rc_channel_data[i]; + report.channel_count = system_state.rc_channels; + report.armed = system_state.armed; + + /* and send it */ + hx_stream_send(stream, &report, sizeof(report)); + } + + /* feed any received bytes to the HDLC receive engine */ + while (read(fmu_fd, &c, 1) == 1) + hx_stream_rx(stream, c); +} + +static void +comms_handle_frame(void *arg, const void *buffer, size_t length) +{ + struct px4io_command *cmd; + + /* make sure it's what we are expecting */ + if (length != sizeof(struct px4io_command)) + return; + + cmd = (struct px4io_command *)buffer; + + /* fetch new PWM output values */ + for (unsigned i = 0; i < PX4IO_OUTPUT_CHANNELS; i++) + system_state.fmu_channel_data[i] = cmd->servo_command[i]; + + system_state.arm_ok = cmd->arm_ok; + system_state.mixer_use_fmu = true; + system_state.fmu_data_received = true; + + /* handle changes signalled by FMU */ + if (!system_state.arm_ok && system_state.armed) + system_state.armed = false; + + /* XXX do relay changes here */ + for (unsigned i = 0; i < PX4IO_RELAY_CHANNELS; i++) + system_state.relays[i] = cmd->relay_state[i]; +} |