PMODE pins on FX3

[Anonymous]

I do not understand the PMODE table that defines pins as being 0,1, or Hi Z.  If a pin is Hi Z, it can be 0 or 1 so that results in entries to the table starting to double up.  If my goal is USB boot, the entry is Z11, which equals 111 or 011 and corresponds to I2C only, I2C with USB on retry, SPI with USB retry, possibly others. 

   

Does cypress mean for you to drive 0 and 1 hard with no pullup or pulldown resistor allowed and then complete disconnect for the Hi Z case?

   

I could see that such a scheme would allow you to test for the HiZ by reading it and then weakly pulling it to the opposite value and reading it again.

[Anonymous · Accepted solution]

 In short, it is Z in the typical electronics sense.

The extended version from our document

Z=Float. The PMODE pin can be made to float either by leaving it unconnected, or by connecting it to an FPGA IO and then configuring that IO as an input to the FPGA

[Anonymous]

We were able to pull with 10K for the Non HiZ pins and it seemed to work.  I wish they would characterize it, but I believe their superspeed explorer kit uses similar pullup or pulldown resistors.