I am attempting to interface to a Test CCA which requires a 1 MHz clock (out of the USB-6221) for both reading and writing. I have three lines. The first line is the 1 MHz Clock, which I have realized this on P0-0. The second line is the write or command line. This line begins with a "start bit" (A transition from a logic 1 to a logic 0 during the period of time that the clock is in it's Logic High state"), and then writes high and low logic values which are read during the time the clock is in it's logic High state. This data stream is followed by a "Stop Bit" (a transition from Logic Low to Logic High during the period of time that the clock is in it's logic High state). I have also implemented this data stream.
The third line is the read line that the UUT responses back on. It begins with the same start bit and ends with the same stop bit as described above. It's data is also read during the period of time when clock is at it's logic High level, also just as above.
Problem: the 1 MHz clock used to write the command to the UUT is also necessary for the UUT to send it's response back to the USB-6221.
QUESTION: how do I write on line (The 1 MHz Clock on P0-0) and read another line (the Command read Line on P01-2) simultaneously?
Thank you in advance for your assistance.
Bruce
