Hail!
Once you wrote to Darryl Gregorash:
 JV> Here's a clip from the Linux kernel. He uses port 80h, which
 JV> shows in a port list as being used for DMA.. Any comments?
   I guess it is in the same latch group that contains all other DMA page 
registers (8xh) but is used in a different way: it's name is "manufacturer's 
diagnostic" and the system BIOS writes there consequently some values showing 
what motherboard test has just passed during the POST. By attaching some 
external diagnostics hardware to this port it thus can be said what test has 
failed.
Farewell!
--- GoldED 2.50+
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