Hi All,
We are developing a low-level code for a certain project. We boot up the
system with our own code, i.e. no DOS/Windows/Unix involved. I have been
trying to find out a documentation on various I/O ports of an IBM PC
compatible system. So far I have found some pre-historic stuff like IBM PC
Technical Reference, dated by 1983...
Specifically, I need to send and receive data over a COM port. I believe
its address is 3F8h. Which register determines baud rate, parity, etc?
Some info about the asynchronous port communication is provided in the '83
reference book, however how valid is it nowadays? Our system is quite
modern: Dell, P4, 3GHz. I thought the documentation for our chipset (865G)
should provide adequate information, but it is of no help unfortunately.
Please help!!!
Alex.

Started up the computer today and the DVD drive is missing from My Computer.

Device manager displays a yellow ! next to
Secondary IDE Controller (dual info )

Reinstalled the driver and yellow ! disappeared but DVD did nor show up.
The yellow ! reappears on every new boot up after driver reinstalled.

Installed a new DVD drive but no luck in it appearing either.

Did a SFC.exe and all appeared okay.

Ran MSD.exe and it does not show the DVD drive.

F1 at IBM logo, and going to disk drives it shows CDrom3 and gives details
as
size installed
local bus IDE mode High performance

HWinfo.exe shows the DVD drive installed at IDE2 as master which is
correct. It also displays the correct model number.

Have checked all cables for seating.
On boot up the DVD light flashes briefly and passes POST.

The Aptiva 2142, 1998 model, is the one with the DVD and Floppy in a console
under the monitor, not in the main tower.

Any ideas why the DVD drive will not show up.

I have a PS/2 Model 33 with two 8mb SIMMs in it.
The BIOS shows 15252k available memory. Could I
get more available memory by replacing one of the
8mb SIMMs with a 4mb (for exactly 16mb total to
start with and avoiding the BIOS disabling any)?

Follow-up to comp.sys.ibm.pc.hardware.misc