okay, for more explanation, this system can be use if you want to use a bus communication on many device, if the distance is not too far(75m is a good example) serial on microcontroller is a good way to "talk" between 2 module, but cannot handle bus communication. The way it work: each device is adressed with 1 byte( 0-255) . the switch device get the ID from each of its client and when a device need to send a message, you must select the client where you want to send the message with it Adress. you can send message up to 64 Byte including transport frame so the message lenght will be limited to 53 byte which is totally sufficient for most of application. Each message is verified with it length & a byte summation. so it will not send bull-- to other device. this is the dynamic way to use the switch. on a second way, the switch can be use on a static way, then when u set the switch parameter, you can set port 2 always go to port 5...etc so you don't need address anymore( usefull for slave/master operation). the transport cable use is a ethernet cable rj45 for conveniance( everyone have it at home) pinout:
1 - 12V
2 - 5V
3 - GND
4 - TX
5 - RX
6 - GND
7 - 5V
8 - 12V
the reason i doubled the power wire is to increase the signal transport lenght ( more cable = less voltage loss)
on an other side, you cannot use a cross-over cable without possibly damaged the system. (I'm still working on the protection circuit )
there is a external power supply connector inside, that permit to add a bigger power supply and the supply the client from the switch.
i'm still working on the manual and spec sheet, I just wanted to have an external view of my project. I made it for my self because i needed it in one of my project and I believe that I am not the only one who would want to use it.