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Full Discussion: Wrong data with Read from a serial port.
Top Forums Programming Wrong data with Read from a serial port. Post 302732913 by Corona688 on Monday 19th of November 2012 10:46:45 AM
Old 11-19-2012
"doesn't work with ioctl" is what you meant, I believe, since if it were working you wouldn't need our help...

I asked before and ask again, is this actually RS-232? If it plugs into USB, the answer is probably no. And if the answer is no, the usual serial niceties like flow control probably aren't going to work how you want, making a lot of fancy termios things pointless.

Code:
unsigned char buf[1000], checksum;
int pos=0;

unsigned char c=0;

while(1)
{
        if(read(fd, &c, 1) <= 0) break;
        buf[pos++]=c;
        if(c == 'm') break;
}

if(c == 'm') read(fd, &checksum, 1);

// Calculate checksum, discard if bad, accept if good

Last edited by Corona688; 11-19-2012 at 11:51 AM..
 

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LEARN ABOUT FREEBSD

umct

UMCT(4) 						   BSD Kernel Interfaces Manual 						   UMCT(4)

NAME

     umct -- Magic Control Technology USB-RS232 converter driver

SYNOPSIS

     To compile this driver into the kernel, place the following lines in your kernel configuration file:

	   device usb
	   device ucom
	   device umct

     Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

	   umct_load="YES"

DESCRIPTION

     The umct driver provides support for USB to RS-232 converters based on the Magic Control Technology USB-232 design.  These devices support
     most of the standard RS-232 features including baud rates ranging from 300 to 115200 bits per second.  However, neither hardware nor software
     flow control seems to be supported.

     Access to devices under this driver is via the ucom(4) framework and device nodes.

HARDWARE

     The umct driver supports the following adapters:

     o	 Belkin F5U109
     o	 Belkin F5U409
     o	 D-Link DU-H3SP USB BAY Hub
     o	 Magic Control Technology USB-232
     o	 Sitecom USB-232

SEE ALSO

     tty(4), ucom(4), usb(4)

HISTORY

     The umct driver appeared in FreeBSD 5.2.  It is loosely based on the ubsa(4) driver by Alexander Kabaev <kan@FreeBSD.org> with documentation
     from Wolfgang Grandeggar <wolfgang@cec.ch>.

AUTHORS

     The umct driver was written by Scott Long <scottl@FreeBSD.org>.

BSD
								 November 20, 2011							       BSD
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