Rockbox mail archive
Subject: AW: AW: AW: AW: AW: Still Problems with AJB Remote
From: Matthias Klumpp (Matthias.Klumpp_at_gmx.de)
# -----Ursprüngliche Nachricht-----
# This schematic is exactly the same (IIRC) as used in old Diode
# Logic (but now only 1-input nand) so it should work...
I confirm, when I think about it.
Therefore I already mentioned (between the lines ;-)) that maybe that
is not as good as it should be.
# What if we used standard 1N4148 diodes?
# The voltage drop on the Schottky diode is 0.6 Volts.
# If the uC out port is at 0 V, the AJB remote line will be pulled
# down to 0.6 V;
Isn't it less voltage drop in case of a Schottky ?
As I understood Jörg, he wants the Schottky because of a lower voltage level
than 0.6V when the uC port is 0V.
# when the uC Out port is at 5 V, the AJB remote is at ~5 V due to
# the pullup.
That's still making me ?????????, because I still have that 5V level on the
What if I make a resistor voltage devider, that makes the pull-up pull to
3.3V, like this:
| |22k |
| | |
uC Out port--------|<|---------+-- AJB remote
# (it's easy to make mistakes though, with this kinda stuff,
# especially since it's holiday - so correct me if i'm wrong)
You are wrong - still NO holidays in Germany ;-)))
Even so it's already a little bit late here and forthermore after a hard
maybe therefore ?
# Perhaps PSPICE has some problems with grounding and stuff; how
# exactly did you connect a ground to this schematic?
Well the schematic is only "the upper half" of the circuit.
I've taken a pulse generator symbol to get a 20ms/5V rectangle signal as the
On the AJB remote side I have a 1M resistor to ground (simulating a high
Page was last modified "Jan 10 2012" The Rockbox Crew