MITTENTITEL

1 18V
2 Data Rx. (Input)
3 Clk Rx. (Output)
4 Load Tx. (Output)
5 Data Tx. (Output)
6 Clk Tx. (Input)
7 Load Rx. (Input)
8 Ground


Cross over - definetly not a network cable.

All signals are filtered.


 

The following tips and tricks were written with greatest care. Nonetheless I will not take any responsibillity or be liable for any damages, including without limitation, special, indirect or consequential damages, or any damages, whatsoever resulting from use this information or rebuilding the described items. This conversion is off the normal limits and will the gurantee on the parts will be lost.

Each terminal has connections for three controllers. To be able to use the macimum of 6 cars you have to use two terminals and connect them with a cable.

In lack of an offical name I call this shuttle connection, just because a shuttle connects terminals.

Physical

The connector is a standard RJ45 8P8C as you know them from network cables. Bit the cables are crossed, so an ordinary network cable will not do. Even worse useing an ordinary network cable can destroy the terminals.

Only one of the terminals must be connected to the power supply(s). This is the master, the terminal without power supply is the slave.

The interface is synchronous full duplex.

Both channels use the same logic, so it is enough to discuss the operation of one channel.

The exact timing differs from terminal to terminal, but it is a synchronous interface, so it's not really relevant.

The transmitter loads its data into a shift register. The the positive edge of the load signal tells the receiver that new data is available.

The receiver will now read bit for bit, requesting a new bit with the positive edge of the clock signal (Clk).

The frequency of the Clk can be up to 400 kHz.

Semantics

What do the terminal tell us ?

Master speaks

About every half second or when a controller on the slave changes the mode (junior/senior) the master tells the slave which controllers have to use which mode.

Bit 7 Parity (even parity)
Bit 6 Always 1
Bit 5

0 when the mode of any controller changd since the last transfer. 1 else.
Bit 4 Always 1
Bit 3

Always 0
Bit 2 When 1, controller 2 of the slave termin shall operate in junior mode.
Bit 1 When 1, controller 1 of the slave termin shall operate in junior mode.
Bit 0 When 1, controller 0 of the slave termin shall operate in junior mode.

Slave chatters

The slave sends the controller data to the master and the master will send it over the track to the cars. This is done about 10 times a second or whenever a change is detected.

Bit 7 Parity (even parity)
Bits 6 bis 5 Id (0-2) of the controller the data belongs to.
Bit 4 0 ehen the lane change button is pressed.
Bits 3 bis 0 Throttle (0-14). A value of 15 represents missing controllers. Those values will not be modified by the master, so it would be possible to make a controller interface that uses 15 instead of 10 speed levels.