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Message: <blockquote data-quote="scottjoh" data-source="post: 448508" data-attributes="member: 20804">Well it depends on which IBUS project.  I have several.  The CD Emulator one is on hold.  I just made a huge order of new PC Boards with various projects on one panel.  The panel contains 16 individual boards with 11 unique designs.  2 of those designs are for IBUS.  One is a IBUS to USB that doesn't use the expensive and hard to get Melexis chip and the other is an IBUS to PIC micro that has 5 discrete outputs (for controlling lights or relays or whatever) and an ePOT for connecting to the wired remote input on Sony or Pioneer head units (IBUS steering wheel controls to control aftermarket head unit.  I know it's been done, but, I'd rather do it myself.)Just reading the I-Bus data to RS-485 shouldn't be a problem.  Well actually RS-485 is a problem since 485 is bidirectional and multidrop differential.  You need to use RS-422 which is similar in that it's +5V differential, but, not bidirectional and multidrop.  There are separate pairs for data in each direction and it's point to point.  Below is a schematic of a IBUS to RS-422 interface which uses a National LMS1485, RS-485 differential transceiver chip as a driver only (because I have some of those chips).  For the I-Bus side I basically have taken the I-Bus read only interface from my I-Bus reader project  <a href="http://ibusmodules.com/Reader.htm" target="_blank">http://ibusmodules.com/Reader.htm</a>  All you need is the BAT54 diode and the 10K Resistor and connect the RX line to pin 4 (DI) of the National Semi LMS1485 RS-485 transceiver.  And pull pin 3 (DE) high.  Added schematic<img src="http://www.ibusmodules.com/Images/IBUS_RS422.gif" alt="" class="fr-fic fr-dii fr-draggable " style="" /></blockquote>

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