The TXDEN pin of the FT232RL is connected to the transmit and receive enable inputs of the SP3485, this line is used to control the transmission mode of the RS-485 transceiver. With the proper drivers installed, the FT232RL will enumerate as a virtual COM port; the drivers are available for Windows, Mac and Linux.
This breakout board includes the SP3485, FT232, TX/RX/RTS LEDs, Mini-B USB connector, filter capacitors, and other components shown on the schematic. We’ve broken out the RS485 output to three different connections: (1) an RJ-45 connector, (2) a 3-pin 3.55mm screw terminal, and (3) a 3-pin 0.1" pitch header; none of these output connectors come populated.
- Fully equipped with SP3485 RS-485 transceiver and FT232RL USB UART IC
- Operates from USB supply
- RX, TX, and RTS LED indicators
- Mini-B USB connector
- USB power and RX/TX lines broken out to a 0.1" pitch header
- RS-485 input/output broken out to RJ-45 connector, 3.5mm screw terminal, and 0.1" pitch header
- Driver/Receiver Enable connected to RTS line of FT232RL
- -7V to +12V Common-Mode Input Voltage Range