NEED HELP...... Can ANYONE send me a Dreawing (or sketch) I dentifying the "PINS" on the Connector coming out of the TMCC Base Unit??

Marty or GRJ

I assume then that Pin 2: Received Data (RXD) will be the “Red” wire out of the cable & Pin 5: Ground (GND) will be the “Green” wire out of the cable!  Have I got that right ?? These will be connected to the TPC's.

Fred

Marty, I thought that Lionel said something about non-standard usage of some of the pins.  I know the transmit, receive, and ground are in the same place, but I believe some or all of the other pins take on different usage.

I think I remember that 2 wires were "crossed" in their harness. Dont quote me as I'm usually wrong. 

E-UNIT-79 posted:

I think I remember that 2 wires were "crossed" in their harness. Dont quote me as I'm usually wrong. 

Which two wires were crossed & “What” Harness ?? Need the Lionel Number for the Harness!

Sorry. I'm not sure and I dont want to give an incorrect answer. Did you try a search because I most likely saw it on ogr. It also might have been on Dale Hs website if it's still up. Was a long time ago.

On the original command base only three pins are used and they are in the "correct" positions for a 9 pin connector.  What is non-standard is the data out which is not at RS232 voltage levels, it is only +5V and 0V levels instead of +12V and -12V.  The input circuit will work with with standard levels or +5V/0V.  Here is the circuit on my reverse engineered schematic.

Cam Bickel

This diagram shows the signal flow with a Legacy base and TMCC base using the Y cable.   Please advise on any errors.

Cam Bickel

MARTYE & GRJ

Have sent both of you E-Mails, but no response. Are you receiving them or are they going in your SPAM or JUNK Files?

Fred

Fred

To go straight to your original question.  The 9 pin connector on the TMCC base is female, so the pin numbering is a mirror of Marty's diagram of a male connector.   If you look closely you should see pin numbers molded into the connector housing.

Pin 1 is in the top row and closest to the U terminal.  The next pin to the left in the the top is Pin 2.  This is DAT.

Pin 5 is COM.  This is the pin in the top row furthest from the U terminal.

Pin 3 is used to send commands into the base.  The base then sends these commands to the track.  This is typically used with accessories that records command sequences.

No other pins are used on the connector on the original base.  The legacy base connector uses more pins as shown in my diagram.

Cam

Cam

Thanks, that confirms my thinking! Appreciate the Confirmation!

Fred

It's my understanding that Lionel uses some of the other pins for non-standard uses with the Legacy base.

Yes, on the legacy base itself all 9 pins are used and these bear little relationship to a standard computer serial port.  The Legacy connector carries three interfaces: the Legacy DAT/TXC/COM connections to accessories, the LCS connections and the Legacy base to TMCC base connections.  On the TMCC base only pins 2, 3, and 5 are used.  I just reverified this on a TMCC Base PC Board.

My diagram is based on continuity testing the Y cable.  Pins 2, 3, and 5 on the Legacy base provide the DAT, TXC and COM signals to the layout corresponding to the same pins on the TMCC base.  Pins 7, 8, 9 of the Legacy base are used for LCS.

Pins 4 of the Legacy base accepts the TMCC base pin 2 DAT signal.  Pin 1 of the Legacy base connects to pin 2 of the TMCC base.  If the Legacy base sends commands to the TMCC base over these pins the TMCC base will send the command to the unconnected U terminal.  However, if a Powermaster bridge is connected instead these commands would be relayed by RF to Powermasters.

The oddball connections are Legacy base pin 6 to TMCC base pin 8, and Legacy base pin 9 to TMCC base pin 9.  There is nothing in the TMCC base on these pins 8 and 9.  I need to check the Powermaster bridge to determine if there are any connections to these pins.   Other than that possibility I don't know what these would be used for.

So pin 5 is used for a earth ground connection which is also the COM terminal on a TPC ? Need to run an earth ground on our club layout which I have done on the previous layout we had in our old location.