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Rockbox mail archiveSubject: BMW IBUS <-> Archos Jukebox (as CD Changer)BMW IBUS <-> Archos Jukebox (as CD Changer)
From: Fernando Birra <fpb_at_di.fct.unl.pt>
Date: Fri, 12 Mar 2004 08:31:36 -0000 Hi, I tried to interface the archos to the BMW IBUS (serial line pulled up to 12V and brounght down to 0 by the talker) but only partailly managed to do it. I have an RS232 adaptor to talk to the bus with a PC and I used it to debug the trasmit routines. So, I can send and receive packets to the bus with the archos with this setup: PC <-> RS232-IBUS adaptor <-> IBUS wire <-> MOSFET Level Shifter (3V-12V) <-> Archos The connections on the MOSFET are: Source - Archos Remote Control Pin Gate - 3V Power Suppy Drain - BMW IBUS However, when I plug the archos with the mosfet level shifter to the car bus I can receive (sometimes with errors) but I cannot send. I managed to identify the problem but I don't know the solution... The trouble is that when I connect the archos to the car bus with the mosfet level shifter (I used a BS170) when the archos forces the bus low it can only bring it to around 1.2 Volts and when I look to the drain pin I still see around 12V. If I short circuit the ground with the source pin then I can bring the drain pin (connected to the car BUS) to around 0V. I really don't know how to solve this and it would be great if you could help me. Would it help connecting to a different MOSFET with a lower Vgs threshold value? Thanks Fernando Birra _______________________________________________ http://cool.haxx.se/mailman/listinfo/rockbox Received on 2004-03-12 Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy |