Gentoo Archives: gentoo-accessibility

From: Keith Wessel <keith@××××××.com>
To: gentoo-accessibility@l.g.o
Subject: [gentoo-accessibility] Advice on serial console configurations?
Date: Wed, 18 Feb 2015 22:56:20
Message-Id: 007301d04bce$197b94e0$4c72bea0$@wessel.com
1 Hi, all,
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5 Hoping someone has more insight into serial console setup than me.
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9 My current system has no on-board serial ports. I've been without Speakup
10 since I moved to it. Not even headers for one. I'm looking for an excuse to
11 by a new mother board.
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15 In the meantime, I've got a SIIG PCI board in there that works fine. It's
16 driving my braille display with brltty just fine. Of course, it uses
17 non-standard I/O addrs and IRQs. But brltty doesn't care about that.
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21 I recently got a docking station for my work Windows laptop that has a
22 serial port, and this was my nudge to use the other port on my PCI serial
23 card to set up a serial console that I can access from Windows. Keeps me
24 from having to get my wife to read the screen to me every time my system
25 won't boot far enough for brltty.
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29 When I add:
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33 console=ttyS0,9600n8 console=tty0
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37 to my kernel command-line, I get nothing in my terminal program on the
38 laptop. I know the connection's working because agetty gives me a login
39 prompt and allows me to log in once the system is booting.
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43 What does happen with the console parameters added to the kernel
44 command-line different from without them is that the system boots very
45 slowly. Takes more like 10 minutes instead of the usual 1 minute to get to a
46 login prompt.
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50 Is this because my serial ports are using non-standard I/O ports and IRQs?
51 Or is Linux smart enough to not assume anything about those? Clearly
52 something's getting it right since the right parameters are getting set once
53 the system has booted and brltty starts.
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57 Can anyone think of any other explanations? Or is it time to buy a new
58 mother board?
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62 Thanks,
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64 Keith