Rockbox.org home
release
dev builds
extras
themes manual
wiki
device status forums
mailing lists
IRC bugs
patches
dev guide



Rockbox mail archive

Subject: AW: Still Problems with AJB Remote
From: Matthias Klumpp (Matthias.Klumpp_at_gmx.de)
Date: 2004-07-10


Hi all,

# -----Ursprüngliche Nachricht (Jörg) -----
# Can't you power the Atmel with 3.3V as well?

Of course I could, but my other signals that I'm emitting need a 5V level.

# > If I connect a open collector transistor stage [...]
#
# Such a transistor stage would invert the signal. I guess the average
# erceiver is not happy with that... ;-)

In fact there are two npn transistors to have the correct logic.

# > Does anybody know, what are the differences of the remote input circuit
# > inside the Studio Player's, old Recorder's and newer
# Recorder's (like V2)
# > ?
#
# Thare should be none, except for the strenght of the pullup.

I think there are some !

If I measure into teh NOT connected remote pin of my Studio, I have 3.3V
-> There is a pull-up

If I do the same with 2 Recorders, I measure 0V.
-> So there is NO pull-up and the input has to be driven actively.

# > Maybe anybody has a schematic ?
#
# See the ducumentation pages.

I did, but unfortunately I'm not able to locate the serial port and its
connection.
Maybe you could give me a hint ?

# The universal bidirectional solution is that circuit with a MOSFET
# inbetween, preventing the voltage to rise above 3.3V. I once
# posted that, am too lazy to dig it out right now.

Any idea which month/year or subject ?

THX

Matthias

_______________________________________________
http://cool.haxx.se/mailman/listinfo/rockbox



Page was last modified "Jan 10 2012" The Rockbox Crew
aaa