Elektor EPROM, Руководство пользователя

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successive addresses. One thing
that might be somewhat annoying is
that the numerical sequence of the
S88 bus modules does not corre-
spond to the output sequence of the
turnout decoders. Consequently, we
have provided a summary in
Table 1 .
EEDTS Pro
short-circuit signaller
We conclude with a small hardware
bonus. In order to advise the EEDTS
Pro 1.2 software of the fact that there
is a short circuit on the track, the
dropping out of the relay in the
booster interface is reported back to
the master controller using the only
remaining free pin of K4 (pin 8).
Whenever a short circuit occurs,
the EEDTS Pro software will stop
sending commands, and it will only
resume sending data after the short
circuit has been remedied and the
interface relay has again been
engaged.
Two alternative booster inter-
faces circuits are shown in Figure 8
and Figure 9 . The first one uses a
relay with two electrically isolated
make or changeover contacts. If all
of the contacts of the available relay
are already being used, the circuit
shown in Figure 9 can be used
instead.
(020125-1)
GENERAL INTEREST
41 11/2002 Elektor Electronics
Figure 7. The Märklin ‘keyboard’ can serve perfectly well as an EEDTS Pro keypad.
Go
5V6
Stop
1N4148
12K
K8
K4
K5
4K7
+5V
020125 - 15
3
5
2
4
1
Go
TIL112
5V6
Stop
1N4148
12K
K8
K4
K5
4K7
+5V
020125 - 16
3
5
2
4
1
Figure 8. A booster interface with short circuit
signalling via relay contacts.
Figure 9. A booster interface with short circuit
signalling via an optocoupler.
Table 1.
Output sequence of the turnout/signal decoders.
EEDTS Pro Märklin S88 Märklin S88 EEDTS Märklin
train address detector lower address upper address turnout/signal decoder turnout/signal decoder
87291-8 87291-1 K83
7 8 16 1a 1 red
6 7 15 1b 1 green
5 6 14 2a 2 red
4 5 13 2b 2 green
3 4 12 3a 3 red
2 3 11 3b 3 green
1 2 10 4a 4 red
0 1 9 4b 4 green