[Wlug] Multiple RS232 Com Ports...

[Mike Frysinger]

On 5/21/07, Stephen Daukas <scd at daukas.com> wrote:
> The *how* is the heart of my question...  If you mean how physically, that's
> a matter of cable and such.

what sort of magic cable ... ive seen implementations where it's a pci
card that hooks up in the back to some octopus monstrosity which is
where the rs232 comes in ...

> The driver question is, again, what I was looking into.  If Linux has
> support for multiple RS232s built in
> to one or more generic drivers in a given distro, then we are talking about
> terminal emulation - a.k.a.
>  VT100 or ANSI or whatever.

you're confusing things i think ... the kernel has drivers for
different devices and that driver exports the multiple device nodes in
/dev/ for userspace to utilize

the important part is making sure a driver exists for your hardware

in terms of other serial devices, there are no real limits in the tty layer

> How do the RS232 FIFO/Interrupts get managed via USB?  In other words, each
> of the RS232s will need to have its "pin-outs" (DB-9) active so the sondes
> believe they are connected in order to avoid their "turning off".

the driver worries about it ?  userspace just sees a serial device in
/dev/ for it to open/configure/write ... if you're interested in
looking at the actual implementation, you should just read the device
driver in the kernel source
-mike