Messages in this thread |  | | Date | Mon, 15 Jan 2001 09:18:38 -0500 (EST) | From | "Richard B. Johnson" <> | Subject | Turn OFF flow-control on a serial link?? |
| |
Hello,
When the 'console' is mapped to a serial device, i.e., /dev/ttyS0, if a terminal, without modem control is connected, no text is displayed.
If a terminal is connected, it is often just 3-wires, i.e, RX/TX/GND. I need to disable modem control, i.e., hardware slow-control. It used to be that CLOCAL was sufficient in the c_cflag member of the termios structure. Then a flag, CRTSCTS was put into c_cflag member also. I could do:
tcgetattr(STDIN_FILENO, &termios); termios.c_cflag &= ~CRTSCTS; termios.c_cflag |= CLOCAL; tcsetattr(STDIN_FILENO, TCSANOW, &termios);
This worked up to Linux version 2.2.17 or thereabouts.
This no longer is the case. It compiles and executes without errors, but does absolutely nothing! So, how do I initialize a serial link to ignore RTS/CTS on version 2.4.0... ?
FYI, I tried......
ioctl(fd, TIOCMGET, &modem); modem &= ~TIOCM_RTS; // modem &= ~TIOCM_CTS; // modem &= ~TIOCM_DTR; ioctl(fd, TIOCMSET, &modem);
... and other such guesses without any success.
Also: `cp textfile /dev/ttyS0` # Waits forever `cat textfile >/dev/ttyS0` # Waits forever but.... `ls >dev/ttyS0` # Executes
Cheers, Dick Johnson
Penguin : Linux version 2.4.0 on an i686 machine (799.53 BogoMips).
"Memory is like gasoline. You use it up when you are running. Of course you get it all back when you reboot..."; Actual explanation obtained from the Micro$oft help desk.
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
|  |