Messages in this thread |  | | Date | Mon, 9 Sep 1996 14:47:08 +0200 | From | Andries.Brouwer@cwi ... | Subject | Re: writing to POST leds? |
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Leonard N. Zubkoff:
: I have one of these also. It's useful for debugging device drivers when : printk's perturb the environment enough to make a bug disappear. : All you need to do is output a value to port 0x80. : However, the SLOW_DOWN_IO code in asm/io.h writes random values : to port 0x80, which tends to obscure the values written by users.
There is also a hook in the keyboard driver that allows a driver to take control of the keyboard leds, so that these continually display three bits of information. Not much, but potentially useful.
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