They are required to deliver +/-5V IIRC, the receiver is required to treat +/-3V or more as valid. This gives 2 volts of noise margin. Bob Ammerman RAm Systems (contract development of high performance, high function, low-level software) ----- Original Message ----- From: "David VanHorn" To: Sent: Thursday, June 14, 2001 12:29 PM Subject: Re: Serial port drive specs. Noncomliant devices? > At 10:12 AM 6/14/01 -0600, Robert Rolf wrote: > >Hi Gang, > > > >I'm using an opto isolator on my RS232 comm lines to a PIC system. > >I have discovered that many portable computing devices DO NOT MEET the > >RS232 spec in that their maximum output is 5V, rather than the 12V > >of the spec. > > They are only required to deliver 3V into a standard load. > > > -- > Dave's Engineering Page: http://www.dvanhorn.org > > I would have a link to http://www.findu.com/cgi-bin/find.cgi?KC6ETE-9 here > in my signature line, but due to the inability of sysadmins at TELOCITY to > differentiate a signature line from the text of an email, I am forbidden to > have it. > > -- > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body