New-bus unit wiring via hints..
韓家標 Bill Hacker
askbill at conducive.net
Fri Oct 12 23:01:58 PDT 2007
John Baldwin wrote:
> On Thursday 11 October 2007 05:59:23 pm Marcel Moolenaar wrote:
>> On Oct 11, 2007, at 2:41 PM, John Baldwin wrote:
>>
*snip*
> on the PCI-ISA bridge of the controlling register) and the fact that COM1 and
> COM2 have de-facto fixed resources on x86, I think it's ok for x86 to include
> default hints for sio0 and sio1.
>
Historically, COM1: - COM(n): assignments were not that hard-and-fast *anyway* -
ergo a once-common BIOS option to reverse them or move 1 or 2 ports within 4
address blocks.
To an extent, the 'complaint' is only that modern BIOS and OS haven't undone
that long legacy of ambiguity, and 'auto' is a 'don't really care' option.
And why try?
The physical serial ports are being phased out on many newer MB. Lucky to get a
header block. Server grade system boards might be expected to keep 'a' serial
port for a while yet, but most laptops have long-since shed them.
Scare resources are perhaps better applied to sorting other 'challenging' bus
device issues.
Such as the vexation that the current rate of progress/economic necessity is
causing I/O devices in general to appear, live a *very* short economic life, and
be replaced by yet-another newer one at a rate that doesn't allow thorough
testing even IF there has been time to code a driver.
That's not limited to F/OSS, either...
:-(
Bill
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