Serial troubles

Apr 23, 2005 3 Replies

Hi !! I'm experimenting some strange behaviors for my Serial ISA pc card. I can read/write on both serials provided by isa card, but only one port works corretly, the remaining one is incredibly slow, while sharing the same configuration. The original serial port is indeed perfecly working, as usual. This are my config: OS: Linux 192.168.0.15 2.4.27 #2 SMP Mo Aug 9 00:39:37 CEST 2004 i686 GNU/Linux cat /proc/interrupts CPU0 0: 388291 XT-PIC timer 1: 8 XT-PIC keyboard 2: 0 XT-PIC cascade 3: 0 XT-PIC ath0 8: 1 XT-PIC rtc 9: 2508 XT-PIC eth0, eth1 11: 0 XT-PIC usb-ohci 12: 11 XT-PIC PS/2 Mouse 14: 32032 XT-PIC ide0 15: 8 XT-PIC ide1 NMI: 0 LOC: 388265 ERR: 0 MIS: 0



# cat /proc/ioports



0000-001f : dma1
0020-003f : pic1
0040-005f : timer
0060-006f : keyboard
0070-007f : rtc
0080-008f : dma page reg
00a0-00bf : pic2
00c0-00df : dma2
00f0-00ff : fpu
0170-0177 : ide1
01f0-01f7 : ide0
02e8-02ef : serial(set)
0376-0376 : ide1
03c0-03df : vga+
03e8-03ef : serial(set)
03f6-03f6 : ide0
03f8-03ff : serial(auto)
0cf8-0cff : PCI conf1 c000-cfff : PCI Bus #01 cc00-cc7f : Silicon Integrated Systems [SiS] SiS530 3D PCI/AGP d800-d8ff : D-Link System Inc RTL8139 Ethernet d800-d8ff : 8139too


Serial driver is loaded as a module in a second stage, when i configure it by setserial, in order to match HW board configuration: After setserial intervention i can read:



/proc/tty/driver# cat serial serinfo:1.0 driver:5.05c revision:2001-07-08



0: uart:16550A port:3F8 irq:4 baud:9600 tx:0 rx:0
2: uart:16550A port:3E8 irq:7 baud:9600 tx:49 rx:15 RTS|DTR
3: uart:16550A port:2E8 irq:5 baud:9600 tx:119 rx:90 RTS|CTS|DTR|DSR|CD

Number "0" is the basic serial port, while "2", "3" are my added ports. Where do I mistake ??



Regards. PS: Serial Card model SUNIX 4031A ISA 16 bit 2S, 16C550 16FIFO


In my experience, that has always been caused by misconfigured IRQ on the "slow" port.

Grant Edwards grante Yow! Everybody gets free at BORSCHT! visi.com

How could I investigate ??

Good question. Here are some ideas:

Take the board out and look at the IRQ jumper, then make sure no other ISA boards are configured to use that IRQ (use the PCI BIOS setup screen to reserve that IRQ for use by ISA boards). You did say it was an ISA serial board, right?

You could try having setserial auto-discover the IRQ. I've never had a lot of luck with that.

Just try configuring the driver for different IRQs until you find one that works.

Remove as much other hardware from the bus as you can.

Grant Edwards grante Yow! I'm having at a tax-deductible visi.com experience! I need an energy crunch!!

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