Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!isc-br!hawk!wddami!wayned From: wayned@wddami.spoami.com (Wayne Diener) Newsgroups: sci.electronics Subject: Re: Current-loop rs-232 <-> rs-232 converter scematics needed Message-ID: Date: 1 Sep 90 22:19:24 GMT References: Sender: uueagle@hawk.isc-br.com (Eagle Proj UUCP login) Lines: 26 >In article huopio@lut.fi (Kauto Huopio OH5LFM) writes: >If anyone has easy scematics for a converter from current-loop rs-232 >to "normal" rs-232, please e-mail here. Our cs club got a printer that I've used the following circuit successfully. I'm not aware of any IC's that do it directly --- Current Loop Side Logic Side +5 ___ | 4N28 +5 R -------- ___ R 2.2K RS232 driver (inverting) 1 | | 6 | R |\ + (source) -----| |--------- |--------| o-----> 2 | | 5 10K |/ C |/ - (sink) -----| |------RRRRR-------| 2N222 3 | | 4 |\ E No Conn. ---| |------RRRRRR---|----| -------- 180K | --- \ / (gnd) --