multicycle and false path detection

[spartacus2]

false path example

Dear folks

Can anybody help me with some tool or program that detects the presence of multicycle and false paths in digital circuits

 

[yuenkit]

what is false path? give an example?

for false path detection, if you are using PrimeTime, u can use 3 commands:

report_timing -justify
report_timing -true
report_timing -false

check the manual or man for further info

 

[joe2moon]

false path detection

For timing constraint file (SDC) checking, please check
1) Cadence's Conformal Constraint Designer (CCD)
https://www.cadence.com/products/digital_ic/conformal/index.aspx

OR

2) FishTail's Focus/Confirm/Refocus
(https://www.fishtail-da.com)

 

[eda_ak]

report_timing justify

Detecting timing exceptions such as Multi-cycle paths is relatively easy while detecting Flase paths is a very tricky business. Often you need to be intimately familiar with the design and is a manual process. And further some valid false paths in RTL may simply vanish after synthesis due to optimization.

Fishtail Design Automation is the only company I know whiich can detect these.

... still learning

 

[yuenkit]

automatic fasle path detection + prime time

there are some design which always give false path.

for example, resource sharing.

if (sel)
out <= a + b;
else
out <= c + d;

this might generate 2 mux block with 1 adder block. a and c are the input for one mux, c and d are for the another mux. timing path will never go from a to d, like wise it will never go from c to b.

 

[spartacus2]

automatic detection of multi-cycle path

Dear friend

I am searching for some free open source tool, to detect the multicycle paths.. for medium size sequential ckts..
Can anyone help me in this regard..
The fishtail products are not open source...

 

[adonics]

false path timing

if anybody can share the fishta1l focus software I can make lic for you. Just for evaluation purpose.
mail to adonics@163.com,best regard.

 

[spauls]

example for false path

You can direclty download demo version
https://www.fishtail-da.com

 

[rascal1125]

false path and multi cycle path

There is a tool called "TimeCraft- Constraint Manager" which can detect precedence conflict between timing exceptions. Also, it will show details about what timing exception is applied on timing path when report_timing.

You can try contacting **broken link removed**