I'm looking for a way to be able to electrically switch between 4-wire and 2-wire RS-485. Up until now I have used jumper connections to establish both communication ways with one circuit. But I would like to be able to switch electronically (from a MCU). An option would for example be a relay, but I don't have the power capabilities for this. Does any of you know of any known circuits that deal with this issue. A figure to describe this issue:
\$\begingroup\$ What will implement data flow-control? \$\endgroup\$– Andy akaJan 16 at 10:09
1\$\begingroup\$ The THVD1424 has this built in. \$\endgroup\$– CL.Jan 16 at 11:28
\$\begingroup\$ Thanks the THVD1424 was exactly what I was looking for \$\endgroup\$– luukitoJan 16 at 12:49
if you use a "2 wire" RS485 drivers you just need to gate the enable signal.
simulate this circuit – Schematic created using CircuitLab