ttyS0 - I only have one serial interface, believe me.

calutateo · 06-24-2005, 03:15 PM

Dear all,

SuSE 9.3, FujitsuSiemens Amilo A, Notebook, 2.6.11.4-21.7-default

I executed the following:

Code:

dmesg | grep ttyS
ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
ttyS47 at I/O 0x8428 (irq = 11) is a 8250
ttyS1 at I/O 0x8440 (irq = 11) is a 8250
ttyS2 at I/O 0x8450 (irq = 11) is a 8250
ttyS3 at I/O 0x8460 (irq = 11) is a 8250
ttyS4 at I/O 0x8470 (irq = 11) is a 8250

I only have one serial interface, believe me.

Could somebody please explain why the command issued ttyS1, ttyS2, ttyS3, ttyS4, and ttyS47?
Any good link for further reading I read the Serial HOWTO (www tldp.org/HOWTO/Serial-HOWTO.html) once but I can't recall that the dmesg command gave such curious output)???

Regards, Carsten

rjlee · 06-24-2005, 05:57 PM

Hmmm… are you certain that you only have one serial interface? Full hardware modems, for example, have full serial interfaces on the card to connect the modem itself to the motherboard.

8250s are cheaper than 16550A (although they have a lower bandwith IIRC) and so they tend to be used more often in embedded serial hardware like this.

You might also look at /proc/ioports and see what else is at these addresses.

calutateo · 06-25-2005, 12:21 AM

Hi,

strictly speaking there are more than one serial port: I have tree USB ports and an internal modem.
Anyway, it is strange that all of ttyS1, ttyS2, ttyS3, ttyS4, and ttyS47 use IRQ 11.

Here is my ioports:

Code:

cat /proc/ioports
0000-001f : dma1
0020-0021 : pic1
0040-0043 : timer0
0050-0053 : timer1
0060-006f : keyboard
0070-0077 : rtc
0080-008f : dma page reg
00a0-00a1 : pic2
00c0-00df : dma2
00f0-00ff : fpu
0170-0177 : ide1
01f0-01f7 : ide0
0200-020f : pnp 00:06
0376-0376 : ide1
0378-037a : parport0
03b0-03bb : RadeonIGP
03d3-03d3 : RadeonIGP
03f6-03f6 : ide0
03f8-03ff : serial
040b-040b : pnp 00:06
0480-048f : pnp 00:06
04d0-04d1 : pnp 00:06
0778-077a : parport0
0cf8-0cff : PCI conf1
4000-40ff : PCI CardBus #02
4400-44ff : PCI CardBus #02
4800-48ff : PCI CardBus #06
4c00-4cff : PCI CardBus #06
8000-803f : 0000:00:06.0
  8000-8003 : PM1a_EVT_BLK
  8008-800b : PM_TMR
  8010-8015 : ACPI CPU throttle
  8018-8027 : GPE0_BLK
8040-805f : 0000:00:06.0
8080-80ff : 0000:00:0a.0
8400-84ff : 0000:00:03.0
8800-88ff : 0000:00:08.0
  8800-88ff : ALI 5451
8c00-8cff : 0000:00:09.0
  8c00-8cff : 8139too
a000-a00f : 0000:00:04.0
  a000-a007 : ide0
  a008-a00f : ide1
a010-a013 : 0000:00:00.0
  a010-a010 : PM2_CNT_BLK
b000-bfff : PCI Bus #01
  b000-b0ff : 0000:01:05.0
fe10-fe11 : motherboard
  fe10-fe11 : PM1a_CNT_BLK

Regards, Carsten

calutateo · 06-25-2005, 12:55 AM

This may help:

Code:

cat /proc/interrupts
           CPU0
  0:    2906365          XT-PIC  timer
  1:       2359          XT-PIC  i8042
  2:          0          XT-PIC  cascade
  7:       4737          XT-PIC  parport0
  8:          2          XT-PIC  rtc
  9:          1          XT-PIC  acpi
 10:       4758          XT-PIC  ohci1394, ohci_hcd
 11:     108713          XT-PIC  yenta, yenta, ohci_hcd, ALI 5451, ndiswrapper, eth0
 12:      96990          XT-PIC  i8042
 14:      27691          XT-PIC  ide0
 15:       5879          XT-PIC  ide1
NMI:          0
LOC:          0
ERR:          0
MIS:          0

yenta = PCICMA driver
ahci_hcd = USB driver
ALI 5451 = internal modem
ndiswrapper = WLAN driver
eth0 = ethernet card

These are all related to /dev/ttySX ???

Regards, Carsten