I try to read serial port on Linux platform using PHP. But I cant read any data. When I try to read using.net, this time I can read. I use 'php_serial.class.php' class for serial port operations. What serial.c or other serial drivers do in order to run. The serial port and keep all of serial communication within the kernel. Thanks, this worked, partially, from the shell I typed: stty -F /dev/ttyUSB0 38400 and this then allowed the LEDs to light via the linux php code.

Hello everyone. I'm trying to connect to a switch through a built-in to motherboard serial port using minicom. I have arch running on vanilla kernel. `zgrep -i serial /proc/config.gz` tells me that CONFIG_SERIAL_8250=y, but `dmesg grep tty` shows only tty0 active. I can't see anything serial port related with neither lspci, lshw, nor lsusb.

I do have /dev/ttyS[0-3] but if I try to cat any of them it gives me input/output error. `setserial /dev/ttyS0` says '/dev/ttyS0, UART: unknown, Port: 0x03f8, IRQ: 4'.

Setting uart to 8250 with setserial did not help:- I also tried starting agetty@ttyS0.service, no luck either. It seems like it *should* work out-of-box. But I can't communicate with the switch:- Can someone please help me get the serial port working? TL;DR: ->Hardware serial port ->Vanilla kernel ->`dmesg grep tty` shows only tty0 ->`setserial /dev/ttyS0` says '/dev/ttyS0, UART: unknown, Port: 0x03f8, IRQ: 4' ->cat: /dev/ttyS0: Input/output error ->Minicom stays dark. ->Thanks for help! Last edited by Hexorg (2013-04-05 15:12:43). It looks like your system is expecting the serial port to exist on the old ISA bus.

Most modern architectures use a (Low Pin Count) bus to provide ISA bus services. The kernel sets up the four legacy MSDOS COM: ports of 0x3f8, 0x2f8, 0x3e8 and 0x02e8 sharing iqq's 3 and 4 and maps them to /dev/ttyS[[0-3]; regardless of whether there is really hardware there. Einstellungstest Pdf Ausbildung Krankenschwester. The question is: How is your serial port actually implemented? Do you know for certain that it is implemented as an legacy ISA device? (Even though the hardware layer may be on the LPC bus?). If it is, is this a BIOS machine?

Are the ports enabled in BIOS, mapped to the addresses the Linux kernel expects? Any chance the serial ports are implemented on a USB or PCI bus interface instead? Edit: Too slow. At least I was on the right path Last edited by ewaller (2013-04-05 15:13:12).