From: David Relson <relson@osagesoftware.com>
To: gentoo-embedded@lists.gentoo.org
Subject: [gentoo-embedded] serial port handling question
Date: Wed, 13 Jan 2010 18:52:40 -0500 [thread overview]
Message-ID: <20100113185240.4bc9d721@osage.osagesoftware.com> (raw)
G'day,
I'm porting some old DOS code to Linux for a medical device that is
being upgraded. Among other goodies, it has a sensor that sends data at
115KB to an onboard NS16550A (or equivalent).
The sensor is controlled (in part) by setting RTS on and off. I looked
high and low (pun intended) for an ioctl or similar call that would
allow this level of control and couldn't find anything. I finally ended
up using the ollowing lines of code:
outb(inportb(MCR) | 0x02, MCR); //DTR,RTS=ON
outb(inportb(MCR) & ~0x02, MCR); //DTR=ON,RTS=OFF
Directly tweaking the I/O port runs against the grain, but it's the
only thing I've found that works.
Is there a better way to control the chip?
Regards,
David
next reply other threads:[~2010-01-14 0:54 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-01-13 23:52 David Relson [this message]
2010-01-14 2:55 ` [gentoo-embedded] serial port handling question Peter Stuge
2010-01-14 4:30 ` David Relson
2010-01-14 5:08 ` Peter Stuge
2010-01-14 10:53 ` Peter Bell
2010-01-14 2:56 ` Daniel Stonier
2010-01-14 3:47 ` Peter Stuge
2010-01-14 4:09 ` David Relson
2010-01-14 10:05 ` Bob Dunlop
2010-01-14 12:29 ` David Relson
2010-01-14 16:17 ` Peter Stuge
2010-01-14 16:21 ` Relson, David
2010-01-14 16:29 ` Peter Stuge
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