unsigned
Mavlink::get_free_tx_buf()
{
/*
* Check if the OS buffer is full and disable HW
* flow control if it continues to be full
*/
int buf_free = 0;
(void) ioctl(_uart_fd, FIONWRITE, (unsigned long)&buf_free);
if (get_flow_control_enabled() && buf_free < FLOW_CONTROL_DISABLE_THRESHOLD) {
/* Disable hardware flow control:
* if no successful write since a defined time
* and if the last try was not the last successful write
*/
if (_last_write_try_time != 0 &&
hrt_elapsed_time(&_last_write_success_time) > 500 * 1000UL &&
_last_write_success_time != _last_write_try_time) {
warnx("Disabling hardware flow control");
enable_flow_control(false);
}
}
return buf_free;
}
std::string get_verbatim_kbinput(WINDOW *win)
{
/* Turn off flow control characters if necessary so that we can type them in verbatim */
if (ISSET(PRESERVE)) {
disable_flow_control();
}
std::string result = get_kbinput(win).verbatim();
/* Turn flow control characters back on if necessary */
if (ISSET(PRESERVE)) {
enable_flow_control();
}
return result;
}
int initialise_uart()
{
// open uart
_uart_fd = open(_device, O_RDWR | O_NOCTTY | O_NONBLOCK);
int termios_state = -1;
if (_uart_fd < 0) {
PX4_ERR("failed to open uart device!");
return -1;
}
// set baud rate
int speed = B250000;
struct termios uart_config;
tcgetattr(_uart_fd, &uart_config);
// clear ONLCR flag (which appends a CR for every LF)
uart_config.c_oflag &= ~ONLCR;
// set baud rate
if (cfsetispeed(&uart_config, speed) < 0 || cfsetospeed(&uart_config, speed) < 0) {
PX4_ERR("failed to set baudrate for %s: %d\n", _device, termios_state);
close(_uart_fd);
return -1;
}
if ((termios_state = tcsetattr(_uart_fd, TCSANOW, &uart_config)) < 0) {
PX4_ERR("tcsetattr failed for %s\n", _device);
close(_uart_fd);
return -1;
}
// setup output flow control
if (enable_flow_control(false)) {
PX4_WARN("hardware flow disable failed");
}
return _uart_fd;
}
unsigned
Mavlink::get_free_tx_buf()
{
/*
* Check if the OS buffer is full and disable HW
* flow control if it continues to be full
*/
int buf_free = 0;
#ifndef __PX4_POSIX
// No FIONWRITE on Linux
#if !defined(__PX4_LINUX)
(void) ioctl(_uart_fd, FIONWRITE, (unsigned long)&buf_free);
#endif
if (get_flow_control_enabled() && buf_free < FLOW_CONTROL_DISABLE_THRESHOLD) {
/* Disable hardware flow control:
* if no successful write since a defined time
* and if the last try was not the last successful write
*/
if (_last_write_try_time != 0 &&
hrt_elapsed_time(&_last_write_success_time) > 500 * 1000UL &&
_last_write_success_time != _last_write_try_time) {
warnx("Disabling hardware flow control");
enable_flow_control(false);
}
}
#endif
// if we are using network sockets, return max lenght of one packet
if (get_protocol() == UDP || get_protocol() == TCP ) {
return 1500;
}
return buf_free;
}
int Mavlink::mavlink_open_uart(int baud, const char *uart_name, struct termios *uart_config_original, bool *is_usb)
{
/* process baud rate */
int speed;
switch (baud) {
case 0: speed = B0; break;
case 50: speed = B50; break;
case 75: speed = B75; break;
case 110: speed = B110; break;
case 134: speed = B134; break;
case 150: speed = B150; break;
case 200: speed = B200; break;
case 300: speed = B300; break;
case 600: speed = B600; break;
case 1200: speed = B1200; break;
case 1800: speed = B1800; break;
case 2400: speed = B2400; break;
case 4800: speed = B4800; break;
case 9600: speed = B9600; break;
case 19200: speed = B19200; break;
case 38400: speed = B38400; break;
case 57600: speed = B57600; break;
case 115200: speed = B115200; break;
case 230400: speed = B230400; break;
case 460800: speed = B460800; break;
case 921600: speed = B921600; break;
default:
warnx("ERROR: Unsupported baudrate: %d\n\tsupported examples:\n\t9600, 19200, 38400, 57600\t\n115200\n230400\n460800\n921600\n",
baud);
return -EINVAL;
}
/* open uart */
_uart_fd = open(uart_name, O_RDWR | O_NOCTTY);
if (_uart_fd < 0) {
return _uart_fd;
}
/* Try to set baud rate */
struct termios uart_config;
int termios_state;
*is_usb = false;
/* Back up the original uart configuration to restore it after exit */
if ((termios_state = tcgetattr(_uart_fd, uart_config_original)) < 0) {
warnx("ERR GET CONF %s: %d\n", uart_name, termios_state);
close(_uart_fd);
return -1;
}
/* Fill the struct for the new configuration */
tcgetattr(_uart_fd, &uart_config);
/* Clear ONLCR flag (which appends a CR for every LF) */
uart_config.c_oflag &= ~ONLCR;
/* USB serial is indicated by /dev/ttyACM0*/
if (strcmp(uart_name, "/dev/ttyACM0") != OK && strcmp(uart_name, "/dev/ttyACM1") != OK) {
/* Set baud rate */
if (cfsetispeed(&uart_config, speed) < 0 || cfsetospeed(&uart_config, speed) < 0) {
warnx("ERR SET BAUD %s: %d\n", uart_name, termios_state);
close(_uart_fd);
return -1;
}
}
if ((termios_state = tcsetattr(_uart_fd, TCSANOW, &uart_config)) < 0) {
warnx("ERR SET CONF %s\n", uart_name);
close(_uart_fd);
return -1;
}
if (!_is_usb_uart) {
/*
* Setup hardware flow control. If the port has no RTS pin this call will fail,
* which is not an issue, but requires a separate call so we can fail silently.
*/
(void)tcgetattr(_uart_fd, &uart_config);
uart_config.c_cflag |= CRTS_IFLOW;
(void)tcsetattr(_uart_fd, TCSANOW, &uart_config);
/* setup output flow control */
if (enable_flow_control(true)) {
warnx("hardware flow control not supported");
}
} else {
_flow_control_enabled = false;
}
return _uart_fd;
}
