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Diffstat (limited to 'README.md')
| -rw-r--r-- | README.md | 12 |
1 files changed, 10 insertions, 2 deletions
@@ -78,7 +78,7 @@ Similarily, on Mac OS X MacPorts or Homebrew can be used to install dependencies On FreeBSD use the following command to install all prerequisites: # pkg install bison flex readline gawk libffi\ - git graphviz pkgconfig python3 python36 tcl-wrapper boost-libs + git graphviz pkgconf python3 python36 tcl-wrapper boost-libs On FreeBSD system use gmake instead of make. To run tests use: % MAKE=gmake CC=cc gmake test @@ -350,6 +350,14 @@ Verilog Attributes and non-standard features through the synthesis. When entities are combined, a new |-separated string is created that contains all the string from the original entities. +- The ``defaultvalue`` attribute is used to store default values for + module inputs. The attribute is attached to the input wire by the HDL + front-end when the input is declared with a default value. + +- The ``parameter`` and ``localparam`` attributes are used to mark wires + that represent module parameters or localparams (when the HDL front-end + is run in -pwires mode). + - In addition to the ``(* ... *)`` attribute syntax, Yosys supports the non-standard ``{* ... *}`` attribute syntax to set default attributes for everything that comes after the ``{* ... *}`` statement. (Reset @@ -413,7 +421,7 @@ Verilog Attributes and non-standard features $ yosys -p 'plugin -a foo -i /lib/libm.so; read_verilog dpitest.v' - Sized constants (the syntax ``<size>'s?[bodh]<value>``) support constant - expressions as <size>. If the expression is not a simple identifier, it + expressions as ``<size>``. If the expression is not a simple identifier, it must be put in parentheses. Examples: ``WIDTH'd42``, ``(4+2)'b101010`` - The system tasks ``$finish``, ``$stop`` and ``$display`` are supported in |