iverilog/tgt-vvp
Martin Whitaker fabdf42365 Fix GitHub issue #356 - use pull strength for tri0/tri1 tie-offs.
When connecting module inout ports, an island is created. If there
is no other driver on one of the island ports, a tie-off is added.
In the case of a tri0 or tri1 net, this must have the correct (pull)
drive strength.

(cherry picked from commit 9d15b771b1)
2020-08-06 14:26:57 +01:00
..
Makefile.in Fix for GitHub issue #96 - support mixed constant/variable delays in vvp. 2016-04-02 20:04:08 +01:00
README.txt Spelling fixes in .txt files 2015-05-25 12:52:03 -07:00
cppcheck.sup Update some cppcheck suppression files 2015-04-08 19:36:21 -07:00
draw_class.c Allow class properties to be arrayed. 2014-09-15 17:37:30 -07:00
draw_delay.c Fix for GitHub issue #96 - support mixed constant/variable delays in vvp. 2016-04-02 20:04:08 +01:00
draw_enum.c updated FSF-address 2012-08-29 10:12:10 -07:00
draw_mux.c Fix for GitHub issue #96 - support mixed constant/variable delays in vvp. 2016-04-02 20:04:08 +01:00
draw_net_input.c Fix GitHub issue #356 - use pull strength for tri0/tri1 tie-offs. 2020-08-06 14:26:57 +01:00
draw_substitute.c Handle some tricky conditions assignments to parts. 2014-07-14 16:46:58 -07:00
draw_switch.c Fix for GitHub issue #96 - support mixed constant/variable delays in vvp. 2016-04-02 20:04:08 +01:00
draw_ufunc.c Spelling fixes 2015-04-13 11:35:12 -07:00
draw_vpi.c Fix potential buffer overflows (GitHub issue #346). 2020-07-28 13:28:21 +01:00
eval_bool.c Remove dead stuff_ok_flags from draw_eval_vec4 functions. 2014-10-24 09:32:32 -07:00
eval_condit.c Fix for br999 - incorrect result from binary comparison. 2016-01-07 19:23:36 +00:00
eval_expr.c Fixed warnings about shifting a negative value 2016-10-14 23:41:11 +01:00
eval_object.c Add support for darray initialisation from another darray. 2017-10-08 17:53:53 +01:00
eval_real.c Remove dead stuff_ok_flags from draw_eval_vec4 functions. 2014-10-24 09:32:32 -07:00
eval_string.c Port %pushv/str to vec4-stack style. 2014-10-24 10:16:35 -07:00
eval_vec4.c Fix GitHub issue #244: handle mixed signed/unsigned power operations. 2019-05-11 21:43:38 +01:00
modpath.c Fix GitHub issue #315 - support modpath delays on multiply-driven nets. 2020-04-02 12:46:57 +01:00
stmt_assign.c Add support for real valued compressed assignment statements in tgt-vvp. 2016-02-23 23:02:23 +00:00
vector.c Remove dead code for allocate_vec handling. 2014-10-24 13:07:53 -07:00
vvp-s.conf.in Remove redundant back-end selections. 2008-09-07 16:43:54 -07:00
vvp.c Update the flag count from 256 to 512 2020-05-31 12:51:41 -07:00
vvp.conf.in Remove redundant back-end selections. 2008-09-07 16:43:54 -07:00
vvp_config.h.in Update header files to use a more standard name to prevent rereading 2014-07-23 13:42:56 -07:00
vvp_priv.h Fix GitHub issue #315 - support modpath delays on multiply-driven nets. 2020-04-02 12:46:57 +01:00
vvp_process.c Add tgt-vvp sorry message for unsupported mixed NB/CA to vector. 2016-05-10 23:02:04 +01:00
vvp_scope.c Fix alloc size warning when building with recent GCC. 2018-10-08 22:10:50 +01:00

README.txt

THE VVP TARGET

SYMBOL NAME CONVENTIONS

There are some naming conventions that the vvp target uses for
generating symbol names.

* wires and regs

Nets and variables are named V_<full-name> where <full-name> is the
full hierarchical name of the signal.

* Logic devices

Logic devices (and, or, buf, bufz, etc.) are named L_<full_name>. In
this case the symbol is attached to a functor that is the output of
the logic device.


GENERAL FUNCTOR WEB STRUCTURE

The net of gates, signals and resolvers is formed from the input
design. The basic structure is wrapped around the nexus, which is
represented by the ivl_nexus_t.

Each nexus represents a resolved value. The input of the nexus is fed
by a single driver. If the nexus in the design has multiple drivers,
the drivers are first fed into a resolver (or a tree of resolvers) to
form a single output that is the nexus.

The nexus, then, feeds its output to the inputs of other gates, or to
the .net objects in the design.