All the tools in prjxray should have an xc7 prefix, so to make them unique.

E.g. bitread or bittool could enter in conflicts with other tools names.

During the work on merging #1419 I figured out that the basic BUFGMUX example works differently on Arty Board and Nexys Video.

The example uses three LEDs:

• led[2] - blinks with slow frequency
• led[1] - blinks with high frequency
• led[0] - blinks with the same frequency as led[2] or led[1] depending on sw[0] state.

On the Arty Board, the example works as intended. On Nexys Video, when

Currently all the columns have different widths, it does not look very good:

It would be nice to make all the widths equal. We need to think about what can be done so the headers are still equally readable.

Maybe we could make them vertical? Or use some kind of an angl

Initially only simple circuits will work, e.g. a counter. As more complicated circuit support is completed, add remaining circuits.

Add inference for 8, 16, and 32 bit wide block RAM.

• See commit below for changes needed brams.txt
• Modify brams_map.v to correctly map {DO,DI} to {A1,B1}DATA
• Add tests to symbiflow-arch-defs

https://github.com/HackerFoo/yosys/commit/13af5854ce244281da05fdf64e57054c6941e41d#diff-f6a92cf62e16c847b9dc035993276826L48

https://github.com/SymbiFlow/yosys/blob/5f900f7891321a6

The testing/mdd_make.tcl program generates a .mdd file which then takes 100 lines of python to parse. Bad use of effort.

Have .tcl output a .json file which can be trivially read. Updates to resulting data structures may be needed (or converted to dictionaries).