Distribution of RS485 Signals
The CONV-TTL-RS485 board uses the Texas Instrument SN65HVD3088E
low-power RS-485 transceiver.
This IC is the fastest in the range and is suitable for applications
that requires signaling rates up tp 20Mbps.
RS-485 Signal characteristics
The following setup was tested in the lab:
RS-485 signal distribution
Data rate and bus length
Bus loading
Termination
The RS-485 differential lines are routed to and from the P2 connector of
the motherboard. The tracks can be 100Ohm terminated, this is optional
and a solid-state relay is used to activate this option.
Two dedicated dip switches on the motherboard can be used to activate,
input or output termination separately. Note however that if termination
is enabled on the input, then it will be enabled on all RS-485 input
channel.
Similarly with output channels, if RS-485 termination is active, then
this will apply to all output channels.
he. RS-485 Signal characteristics in the CONV-TTL-RS485 board