How to read Scan infomation from a scan inserted netlist in mentor DFT ADVISOR?????

[wolve4]

I am given a scan stitched gate level netlist (180 nm ) , and a scan sdc, funcional sdc (apart from this no other information is given )and a library file. I was asked to check the correctness of the scan chain in the netlist and redump the netlist and scan def. The Design has a TMX module wich generates all the scan signals (even the scanin data signal is generated by the TMX module....the design has no compression ) . The problems I am facing are


1)The scan mode is an internally generated signal. The case analysis for the scan mode is given in SDC but I didin't find a command which helps me constrain the internal instance which generates the scan mode signal in DFT advisor manual.

2)To use the add_scan_chains command the scanin and scanout pins should be a primary input/output. But in the netlist the scanin pin is a instance output pin present in the TMX module. So I am unable to add the existing scan chains in the design.

3)The same netlist is ported to 45nm using a 45nm library. so obviously the chain will be broken as the insatnce and insatnce-pin name differs in 45nm libs. So how can we do scan insertion for the 45 nm netlist (which already has scan flops ).

I would be pleased , if I get a flow of how we can read in the scan information of prescan inserted netlist in DFT ADVISOR with the above given infomation adn dump out a log file.

I would also like to know "Can we delete the scan information ( LIke the scan pins, stitched scan chain etc ) and re insert scan if we have only the above given (mentioned i the first line) information.

Thanks in advance

 

[maulin sheth]

I am more interested to know about TMX module. Because as per information which is given by you, it directly mean that - > all scan portions are handeled by TMX module.
Have you a .testproc and .dofile which contain the scan chain information like.. How many scan chains you have?

So please can you give me the information of TMX module.

You can access the internal instance. For that you just need to use hook up option. I dont know the command for hook up...But you can find in the user guide that how you can hook up the internal net to top level pin?

 

[Nanda San]

You must be having a similar command in DFTAdv. as in DFTC for adding a scan mode signal as below.

set_dft_signal -view spec -test_mode all_dft -type TestMode -active_state 1/0 -hookup_pin { path to the instance name } (if no compression is used)

you need not use the add_scan_chains command at all. Are you trying to direct the tool to create some dedicated scan chains for a particular macro ?

If you're using a scan inserted netlist already you must be having a test model like .ctl or something ??? If you don't wish to use this test model you might try loading the gtech databse in DC and reinsert scan.