Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!gatech!bloom-beacon!oberon!pollux.usc.edu!papa
From: papa@pollux.usc.edu (Marco Papa)
Newsgroups: comp.sys.amiga.tech
Subject: Re: drop DTR
Message-ID: <15434@oberon.USC.EDU>
Date: 18 Feb 89 07:31:44 GMT
References: <8902172041.AA06747@postgres.Berkeley.EDU>
Sender: news@oberon.USC.EDU
Reply-To: papa@pollux.usc.edu (Marco Papa)
Organization: Felsina Software, Los Angeles, CA
Lines: 42

In article <8902172041.AA06747@postgres.Berkeley.EDU| dillon@POSTGRES.BERKELEY.EDU (Matt Dillon) writes:
|:I (Marco Papa) write:
|:of a serial device will NOT drop DTR.  Doing instead:
|:
|:CloseDevice(..);
|:Delay(50L);
|:OpenDevice(..);
|:
|:will ALWAYS drop the DTR line.  This is all from "empirical" results
|:using the built-in serial device.  I have NEVER been able to have the
|:DTR line dropped on ANY of my modems WHITHOUT the 1 sec. delay.
|
|	Also, remember that you must make an SDCMD_SETPARAMS call after
|reopenning the serial.device to get back whatever your old serial
|modes were.  I always have an auxillary IOExtSer structure with the
|modes I want.  Remember to specify a dummy request in the OpenDevice()
|(as opposed to the aux structure which has your original modes)
|because the serial.device will overwrite it with the default prefs
|params.

Yes, the whole thing looks like this in A-Talk III:

DropDTR()
{
MyAbortIO(Read_request);
CloneSer(Read_request,local);		/* copy the IOExtSer byte by byte */
CloseDevice(Read_request);
Delay(50L);
OpenDevice(serdevice, serunit, .....);	/* check for errors, of course */
CloneSer(local, Read_request);
CloneSer(local, Write_request);
SetParams(Read_Request);
InitRWCommands();		/* reset CMD_READ, CMD_WRITE in io_Command */
}

Works like a champ!

-- Marco Papa 'Doc'
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
uucp:...!pollux!papa       BIX:papa       ARPAnet:pollux!papa@oberon.usc.edu
 "There's Alpha, Beta, Gamma and Diga!" -- Leo Schwab [quoting Rick Unland]
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=