I am trying to echo some string to /dev/ttyS0 and the rx and tx stats in /proc/tty/driver/serial remain 0. If I change the irq of ttyS0 to 0 and then echo some string to ttyS0, the stats are changing according to the length of the string. Would anyone be able to help me with this?
output of setserial -g /dev/ttyS[0123]
/dev/ttyS0, UART: 16550A, Port: 0x03f8, IRQ: 11
/dev/ttyS1, UART: 16550A, Port: 0x02f8, IRQ: 10
/dev/ttyS2, UART: unknown, Port: 0x03e8, IRQ: 4
/dev/ttyS3, UART: unknown, Port: 0x02e8, IRQ: 3
output of stty -F /dev/ttyS0 -a
speed 115200 baud; rows 24; columns 80; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S;
susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; discard = ^O; min = 1; time = 0;
-parenb -parodd -cmspar cs8 hupcl -cstopb cread clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -ixon -ixoff -iuclc -ixany -imaxbel iutf8
opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
-isig -icanon -iexten -echo -echoe -echok -echonl -noflsh -xcase -tostop -echoprt -echoctl -echoke -flusho -extproc
out put of cat /proc/interrupts for irq 11 with 16 cpu.
11: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 IO-APIC 11-edge ttyS0
output of cat /proc/tty/driver/serial:
0: uart:16550A port:000003F8 irq:11 tx:228 rx:0 RTS|DTR|DSR|CD|RI
1: uart:16550A port:000002F8 irq:10 tx:0 rx:0 CTS|DSR|CD|RI
2: uart:unknown port:000003E8 irq:4
3: uart:unknown port:000002E8 irq:3
As i said I have tried to change thee irq to 0 and it worked. But what is wrong with irq 11. There is no deviced registered for irq 11 in /proc/interrupts except ttyS0.
