Dear everyone,
I am a software engineer working on QNX platform. Now I have a problem and need help.

1. I get a PCI-bus Multi Serial port card. This card can provide 8 serial ports.

2. I plug this card in QNX platform.

3. I use the show-pci utility to this card, this utility tell me that this card's IRQ is 10 and the I/O base address is 0xb800, so the I/O base
address for the 8 ports are 0xb800, 0xb808, 0xb810, 0xb818, 0xb820, 0xb828, 0xb830, 0xb838

4. Can I directly use the command "Dev.ser 2f8,3 3f8,4 b800,10 b808,10 b810,10 b818,10 b820,10 b828,10 b830,10 b838,10 &" to map COM1, COM2 and 8
serial ports to /dev/ser1, /dev/ser2, /dev/ser3, /dev/ser4, /dev/ser5, /dev/ser6, /dev/ser7, /dev/ser8, /dev/ser9, /dev/ser10 ?

5. If the answer is not. Does it mean that I have to write a device driver for this multi serial port card ? Can you tell me how to do it ?

6. In this architecture, the /dev/ser3 ~ /dev/ser10 share the same IRQ 10. Does it will affect the data transfer rate and data accuracy ?


Best Regards,


Rick Lee

 

>1. I get a PCI-bus Multi Serial port card. This card can provide 8 serial ports.
>2. I plug this card in QNX platform.
>3. I use the show-pci utility to this card, this utility tell me that this
>card's IRQ is 10 and the I/O base address is 0xb800, so the I/O base
>address for the 8 ports are 0xb800, 0xb808, 0xb810, 0xb818, 0xb820, 0xb828, 0xb830, 0xb838

Are there addresses assigned to the base address registers ??

>4. Can I directly use the command "Dev.ser 2f8,3 3f8,4 b800,10 b808,10
>b810,10 b818,10 b820,10 b828,10 b830,10 b838,10 &" to map COM1, COM2 and 8
>serial ports to /dev/ser1, /dev/ser2, /dev/ser3, /dev/ser4, /dev/ser5,
>/dev/ser6, /dev/ser7, /dev/ser8, /dev/ser9, /dev/ser10 ?

No ... I don't believe. It depends on the design of the PCI interface. The register sets of the serial controllers are mostly mapped into memory ... so the driver doesn't use port IO.

>5. If the answer is not. Does it mean that I have to write a device driver
>for this multi serial port card ?

I'm afraid ... yes.

>Can you tell me how to do it ?

Good question ;-) ... Try to get at first a specification of the hardware interface of that board.

>6. In this architecture, the /dev/ser3 ~ /dev/ser10 share the same IRQ 10.
>Does it will affect the data transfer rate and data accuracy ?

No -> if your board has a co-processor -- probably yes -> if your board is a passive one. The capability to buffer the character stream is also important ...

Regards

Armin Steinhoff