Reg executing BIST

[vignesh_v]

hi,

   Im using MPC5777c for my project which is basically a diagnostic sw for which i need to perform RAM and ROM tests and based on the success i shall perform other tests or exit . 

to achieve the purpose I need to use the BIST module, in doing so do i need to go for online test or offline test which is more suitable. I feel to go with online tests. Please advice / suggest on the same.

if offline tests need to be performed i think as per my understanding i cant use the DFF record and cmm script file used /genarated using lauterbach  as provided in the examples. Im using s32 design studio how to use/create DCF records and run the tests in offline mode. Pl do suggest .

Adding one more Query .

Im using following configuration for PLL can the same be used to run MBIST. As i noted in example and Application note the PLL values are different

PLL0 to 192MHz (40MHz XOSC reference)
PLL1 to 264MHz (48MHz PLL0 PHI1 output reference)

Thanks in Advance,

Vignesh

[vignesh_v]

Thanks ,

           As per the suggestion il use the recommended settings for running MBIST and for my application i shall  later change the PLL settings as i have done my peripheral settings based on that. hope its possible to do like that.

On seeing the example now i have a fair idea how to execute online tests. but regarding offline test im not sure how to do DCF record and load the same and how to execute the offline tests for MBIST.

im using PE Micro and s32 design studio. does the calculation procedure vary?

and how can i run offline tests is it only through scripts.? or it can be run like online tests in code after startup?

im a bit confused on these 2 items. it will be much appreciated if explained.

Thanks in Advance,

Vignesh

[petervlna]

Hi,

As per the suggestion il use the recommended settings for running MBIST and for my application i shall  later change the PLL settings as i have done my peripheral settings based on that. hope its possible to do like that.

Yes. After offline BIST the reset is executed (due to ECC errors in memories - BIST do not work with ECC and thus syndromes in memories will not match correct ECC) so all configuration made to PLL are lost. The device will start with default clock. (IRC or XOSC)

You have to configure the PLL in your application.

On seeing the example now i have a fair idea how to execute online tests. but regarding offline test im not sure how to do DCF record and load the same and how to execute the offline tests for MBIST.

This is why you should follow example Lauterbach scripts attached to AN5288 for offline BIST.

Im using PE Micro and s32 design studio. does the calculation procedure vary?

PE uses S-record for this purpose. So you have to create S-record file and load it with PE to micro.

To make it simpler we have created DCF calculators which also provides s-record format for PE:

Calculators are here:

MPC5777C DCF Configurator 

and how can i run offline tests is it only through scripts.? or it can be run like online tests in code after startup?

Once you program Offline tests configuration in TEST memory via DCf records, the tests will be started when SSCM machine read last DCF record which contain start bit for STCU offline test.

I know that the self-test configuration is not simple when you see it first time.

This is why we publish AN5288.

regards,

Peter

[vignesh_v]

Thanks A lot. I shall look into it.

Regards,

Vignesh

[petervlna]

Hi Vignesh,

in doing so do i need to go for online test or offline test which is more suitable. I feel to go with online tests. Please advice / suggest on the same.

Usually you perform both tests.

Offline self test is essential fro safe application as it tests memories and logic during reset phase. So after reset, when micro starts execution, you can rely on HW correct functialitty.

Furthermore the online self-test is executed on end of application execution to discover possible faults which can happen during application execution.

if offline tests need to be performed i think as per my understanding i cant use the DFF record and cmm script file used /genarated using lauterbach  as provided in the examples. Im using s32 design studio how to use/create DCF records and run the tests in offline mode. Pl do suggest .

You can program DCF records from application or use other debugger than Lauterbach. (for example PE)

But in S32DS you can easily install Lauterbach plugin if you have such device:

HOWTO: Install Lauterbach TRACE32 debugger plug-in into S32 Design Studio 

Im using following configuration for PLL can the same be used to run MBIST.

I recommend you to use the PLL configuration from application note as the BIST was tested on this configuration.

Set PLL0 dividers to output 50 MHz at PLL0_PHI. When using the PLL for the Off-Line BIST, the XOSC is the PLL0
reference clock by default and cannot be changed.

Generally on all MPC57xx devices the offline BIST frequency is 50MHz. If you execute memory BIST only you can go up to 200MHz.

https://www.nxp.com/docs/en/application-note/AN5288.pdf 

regards,

Peter