Hi
I have a vintage (model train controller Hornby Zero1) TMS1000 chip that outputs onto a 2 wire bus to which receivers are attached.
Feasability - Is it possible to take the output(result of keyboard entries from the TMS1000 2 wire bus and feed it into a Arduino Uno etc, and then place that output ) from the Arduino, onto a 2 wire bus. Result should be exactly the same and usable to be read by the receivers. Basically just passes the same data straight thru to output, but now on a progamable chip.
Reason is, at a later stage is to have a second Arduino with its own keyboard to produce data for a second bus (same type of data ). And next stage is to take bus #1 and #2 onto a third (if necessary?)Arduino and insert one output into the other bus. End up with a single 2 wire bus to receivers. That is to combine data bus periodically (say every 500ms to 1 sec)
This is a project to increase the number of locomotive addresses on TMS100 to more than 16, without modifying the original controller.
So keyboad 1 on the TMS1000 used as normal. Keyboard on Arduino to use numbers above 16 with speed and direction data, then becomes 1 data stream covering loco addresses from 1 to say 64.
Main thing is to see if part 1 above is feasible to start with.
All comments will be much appreciated.
Thanks
Charles Harris
The Arduino Mega offers also a parallel bus interface. It works only for reading external devices, not as a peripheral device to the original processor.
The document in the link posted in #2 explains how you could possibly interface with the locomotives directly, without the need of a separate microcontroller (such as the TMS1000). Of course you still need to find or build appropriate additional electronics to get the signal onto the power supply line.
You will have a lot of study to do as you will have to understand the signal and how it is all multiplexed on top of each other. Sounds like a fun project, and very satisfying when pulled off.
If you want to communicate with the TMS1000 you'll have to figure out voltage levels of that 2-wire bus, how the data is encoded on it, and what the actual commands are that this chip expects.