A question regarding the PXI-8431/8 serial port card: Is it possible to directly control the TX (transmit) & read the state of the RX (receive) lines? I need to implement a serial communication scheme using separate data and clock similar to SPI using differential line drivers.
Looking at the RS-485 Transceiver Control.vi example, I see that it is possible to control the state of the serial port control signals, CTS, DCD, DSR, DTR, RI, and RTS.
You will not be able to directly control the TX & RX lines because the PXI-8431 is specifically designed for RS-485/422 protocol. The transmit and receive lines will always expect a serial packet. Yes, you can control the serial port control signals, but not the TX & RX lines directly. It would probably be better to get a chip specifically designed for the protocol you are trying to use.