Article View: comp.sys.amiga.tech
Article #11271Re: DTR and serial.device
From: Perry Kivolowitz
Date: Tue, 31 Jan 1989 06:42
Date: Tue, 31 Jan 1989 06:42
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1752 bytes
Marco's suggestion to access the CIA registers directly for toggling
DTR is *not* a good idea for the following reason: No other serial
port besides the internal one uses the CIA.
In other words, in this as in all things, going to the hardware
directly will bind you into some pretty severe limitations. In this
case manipulating DTR in the suggested manner is a sure file way to
never be able to use expansion serial ports.
Another suggestion:
(Bryce are you listening? :-)
In an earlier incantation of my serial device driver I added a command
which would allow access to all setable outputs. Something like:
io_Command = CMD_SET_SERIAL_CTRL_LINES;
io_Length = MASK_OF_BITS_TO_BE_AFFECTED;
io_Actual = WHAT_TO_SET_THEM_TO;
DoIO(IOB)
If we all agree to make this a standard, well then, it will become a
standard.
Note: My current serial device driver (the one that deals quite nicely
with 115KB :-) does not have this feature anymore but I might add it
back in if there's any requests.
--
Perry Kivolowitz, ASDG Inc.
ARPA: madnix!perry@cs.wisc.edu {uunet|ncoast}!marque!
UUCP: {harvard|rutgers|ucbvax}!uwvax!astroatc!nicmad!madnix!perry
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<443@madnix.UUCP>Path:
arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!nrl-cmf!ukma!xanth!nic.MR.NET!umn-d-ub!uwvax!astroatc!nicmad!madnix!perryReferences:
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!nrl-cmf!ukma!xanth!nic.MR.NET!umn-d-ub!uwvax!astroatc!nicmad!madnix!perry From: perry@madnix.UUCP (Perry Kivolowitz) Newsgroups: comp.sys.amiga.tech Subject: Re: DTR and serial.device Summary: Not A Good Idea Keywords: serial, RS232, modem Message-ID: <443@madnix.UUCP> Date: 31 Jan 89 06:42:09 GMT References: <10511@well.UUCP> <15000@oberon.USC.EDU> Reply-To: perry@madnix.UUCP (Perry Kivolowitz) Distribution: usa Organization: ASDG Incorporated Lines: 35