This reverts commit 577cc12fe0.
Reverting the change from issue #16. After some discussion, it has
been decided that it is up to the user to implement the pull-up and
pull-down modes correctly by setting the output enable and driving
the output to the appropriate value. Note that this should be well
documented, if by nothing else than a validation testbench that
excercises a user pull-up and pull-down input mode.
from the data and replace them with a single flop clocked on the
negative edge of the serial clock. This will completely avoid hold
violations by ensuring that the block's output data bit does not
change anywhere near the clock rising edge, so clocks do not have
to be tightly aligned among all of the GPIO blocks.
* Fix syntax error in gpio_control_block
Fixed syntax error that was only visible when running iverilog for simulation
* Apply automatic changes to Manifest and README.rst
Co-authored-by: marwaneltoukhy <marwaneltoukhy@users.noreply.github.com>
fixed by moving from after the managment protect to before it, but
an inversion of the signal was missed, leading to an incorrect
wb_rst_i passed to housekeeping. (2) Revised the method to load
the serial GPIO data chain from a 2-pin, I2C-like method to a
more straightforward 3-pin method with separate reset, clock, and
load pins. The load pin propagates through the chaing like the
other two. Added a bit-bang signal for the load signal as well.
(3) Added an implied buffer after the data output of the GPIO
control block to ensure that the data arrives at the next control
block after the clock, to prevent hold violations.
via programming. The values for each of the GPIOs at power-up are
defined in the "user_defines.v" file. For the verilog, they are
applied as parameters. For the layout, they will need to be
separately defined cells for each of the GPIOs, or at least for
each set of unique default values.
Tim Edwards
Marwan Abbas
Kareem Farid