correspondence of unused i/o pins to physical connector location?

Your table is missing the channel data, not sure why, but this is what I get:

IO Connections for TB1/TB2 -> 7I96_1
Pin#                  I/O   Pri. func    Sec. func        Chan     Sec. Pin func   Sec. Pin Dir

TB1-2,3                17   IOPort       StepGen          0        Step/Table1     (Out)
TB1-4,5                18   IOPort       StepGen          0        Dir/Table2        (Out)
TB1-8,9                19   IOPort       StepGen          1        Step/Table1      (Out)
TB1-10,11            20   IOPort       StepGen          1        Dir/Table2        (Out)
TB1-14,15            21   IOPort       StepGen          2        Step/Table1      (Out)
TB1-16,17            22   IOPort       StepGen          2        Dir/Table2        (Out)
TB1-20,21            23   IOPort       StepGen          3        Step/Table1      (Out)
TB1-22,23            24   IOPort       StepGen          3        Dir/Table2        (Out)
TB2-2,3                25   IOPort       StepGen          4        Step/Table1      (Out)
TB2-4,5                26   IOPort       StepGen          4        Dir/Table2        (Out)
TB2-7,8                27   IOPort       QCount            0        Quad-A            (In)
TB2-10,11            28   IOPort       QCount            0        Quad-B            (In)
TB2-13,14            29   IOPort       QCount            0        Quad-IDX         (In)
TB2-16,17            30   IOPort       SSerial             0        RXData0          (In)
TB2-18,19            31   IOPort       SSerial             0        TXData0          (Out)
Internal-TXEn       32   IOPort       SSerial             0        TXEn0             (Out)
Internal                33   IOPort       SSR                  0        AC Ref            (Out)

Default firmware on a 7I96S is 7i96s_d.bin

 

Oops. I've edited the table to a more convenient/compact format, and I had already edited that column out of mine, because I didn't think "Channel" was interesting (to me, at least). I hadn't realized what it represents.

Thanks.

Slightly outside the original topic: pncconf lets me reconfigure what is by default an input (e.g., the Quad B i/o #28) into an output (e.g., "Machine is enabled"). Does the board really allow that? And if so, are the +/- pins for that input now complementary outputs?

paul

No, the driver will not allow that unless you disable the encoder function
and the encoder pins are always inputs on a 7I96s (hardware determined)

Thanks -- empirical evidence agrees with you.

For future reference, is this also true of the P1 inputs -- are they also locked as inputs, assuming the default firmware?

On bare FPGA pins (like on P1) any pin can be an input or output
_IF_ if it's  secondary function is disabled (or it has no secondary function)
Secondary functions can be disabled in the hal file with the num_xxxx=N stanzas

For example, the default 7I96S firmware has just GPIO (no secondary function)
on P1 so all P1 pins can be input or output. On a more complex configuration
say 7i96s_5abobd, the P1 pins used for the second encoder inputs can only be
inputs unless you disable the second encoder in the hal file (num_encoders=1)
(this leaves the encoder on the 7I96S card itself enabled)


The hostmot2  manual page has more details


 

The inputs and outputs on TB3 are described on Page 10 of the document you shared

Yup -- but I was asking about the TB1/TB2 pins. They're listed on the preceding pages, but only with their step/encoder/serial functions. Not as I/O pins.

For example on TB2, if you set num_stepgens to 4, the TB2 step04/dir04 pins become
available as GPIO, but they only work as outputs because they have a buffer with its inputs
from the FPGA and outputs on TB2.