Hi All !
I have to test two types of encoder chips with a microcontroller. One has RS485 outputs, other just 3.3V standard single ended TTL outputs.
Is it possible to connect both types of signals to an RS485 receiver input and get a correct data on the receiving side ( mocrocontroller input ) ?
Obviously the only problem is how to get the single ended encoder signal trough the rs485 receiver...
I have no spare pins on the external connector to use separate I/O lines for the different encoders, so I have to use the same lines for TTL as for the differential inputs.
I was thinking..in case of TTL I can connect 3.3v output to line B, and tie line A to GND...
It will be up to user to use the correct connector for different encoders.
So...>
if B = 0 (LOW) : A-B = 0 ...output should be 1
if B = 3.3v (HI) : A-B = -3.3 ...output should be 0
The output would be inverted but that's not an issue.
All the encoders and the microcontroller are using 3.3v supply. The micro will be actually a Tiva launchpad.
Am I missing something or it really should be that easy ?
Is there any RS485 receiver/transciever that should suit this more than others?
Thanks,
Attila