The `ports` argument to the `convert` functions is a frequent hotspot of
beginner issues. Check to make sure it is either a list or a tuple, and
give an appropriately helpful error message if not.
Fixes#362.
The evaluation version of Verific prints its license information to stdout,
and since it is against the EULA to change that in any way, this behavior
is not possible to fix in Yosys. Add a workaround in nMigen instead.
nextpnr now supports -12k; which replaces the use of -25k and --idcode
together to build bitstreams compatible with -12F devices. Use this.
This also removes the LFEUM-12K and its 5G counterpart; as per Dave Shah
they're currently only theoretical FPGAs.
By default, if an operation produces an undefined value (a Jinja2
concept that corresponds to Python's KeyError, AttributeError, etc)
then this value may be printed in a template, which is a nop. This
behavior can hide bugs.
This commit changes the Jinja2 behavior to raise an error instead of
producing an undefined value in all cases. (We produce undefined
values deliberately in a few places. Those are unaffected; it is OK
to use several kinds of undefined values in one Jinja2 environment.)
Fixes#337.
Such wires are likely to trigger pathological behavior in Yosys and,
if applicable, other toolchains that consume Verilog converted from
RTLIL.
Fixes#341.
Before this commit, selecting a part that was fully out of bounds of
a value was correctly implemented as a write to a dummy wire, but
selecting a part that was only partially out of bounds resulted in
a crash.
Fixes#351.
The default __repr__() from typing.NamedTuple does not include
the module name, so the replacement (which uses the preferred syntax
for specifying these shapes) doesn't either.
This has been originally implemented in commit d3775eed (which fixed
`write_vcd(traces=)` to do something at all), but had a flaw where
undriven traces would not be correctly placed in hierarchy. This
used to produce incorrect results on pyvcd 0.1, but started causing
assertion failures on pyvcd 0.2.
Fixes#345.
This commit improves handling of resets in AsyncFIFO in two ways:
* First, resets no longer violate Gray counter CDC invariants.
* Second, write domain reset now empties the entire FIFO.
In some cases, it is necessary to synchronize a reset-like signal but
a new clock domain is not desirable. To address these cases, extract
the implementation of ResetSynchronizer into AsyncFFSynchronizer,
and replace ResetSynchronizer with a thin wrapper around it.
Because write_vcd() is a context manager, this is useful if the VCD
file should be sometimes not written, since it avoids awkward
conditionals with duplicated code. It's not very elegant though.
Fixes#319.
For most toolchains, these are functionally identical, although ports
tend to work a bit better, being the common case. For Vivado, though,
it is necessary to place them on the port because its timing analyzer
considers input buffer delay.
Fixes#301.
Before this commit, there was no way to do so besides creating and
assigning an intermediate signal, which could not be extracted into
a helper function due to Module statefulness.
Fixes#292.
Before this commit, doing something like:
with m.FSM():
with m.State("FOO"):
m.next = "bAR"
with m.State("BAR"):
m.next = "FOO"
would silently create an empty state `bAR` and get stuck in it until
the module is reset. This was done intentionally (in Migen, this code
would in fact miscompile), but in retrospect was clearly a bad idea;
it turns typos into bugs, while in the rare case that branching to
a completely empty state is desired, it is trivial to define one.
Fixes#315.
Before this commit, only signals driven from fragments (in practice,
everything except toplevel inputs) would get written to a VCD file.
Not having toplevel inputs in the dump made debugging ~impossible.
After this commit, all signals the fragment refers to get written to
a VCD file. (More specifically, all signals the compiler assigns
an index to, i.e. signals the generated code reads or writes.)
Fixes#280.