Hi,
I would like to create a simple general logic hub, half duplex, 3.3V, as in the design below. I looked at your RS485 design example as a reference as well. In my design, the direction is controlled by a microcontroller.
At the moment, I think about using 74AC245 as direction controlled transceivers. However, they do not have separate R/D lines. That means that in the direction (N to 1), the signal has to go through a OR or AND gate (depending on idle low or high of the signal).
In the 1:N direction (from left to right in the sketch), however, I would need a direct connection to the transceivers without a gate, because the gate does not work in that direction.
The solution I can think of with components I know is to integrate a switch in the design that bypasses the gate when communicating in the 1:N direction. But I am looking for better solutions. This is where I could need some help:
- Is there a component that works as a AND or OR gate in one direction and as a simple fan-out buffer in the other direction? One that simply replaces the gate?
- Are there equivalents to 74AC245 (or similar) transceivers that have separate lines for communication in two directions on one side of the transceiver (just as the transceivers you are using in your RS485 reference design, but not using RS485 signals but general logic 3.3V?) To the outside world, I still need one single half-duplex signal line.
- Or is there a bidirectional component integrating transceivers and gate? A general logic hub component?
- Or is there a better, simpler concept to achieve this hub?
Thanks in advance, I hope to get some more insights here.
Christoph
PS I don't need auto-direction detection
