MIMXRT1170 Scatter Files and Init Files

[Desmond_lim]

Hi NXP experts,

As we are trying to create our base code using the SDK example provided, we came across different scatter files and init files which we need to understand what those scatter files are created for.

We are using KEIL MDK for our development and as we ran through some of the examples, we noticed that some of the SDK contains different scatter and init files, for instant, in the demo_apps (hello_world), there are 6 different types of scatter files and ini files. These files are not a problem for us however, it is a problem for us when some of the scatter file we choose will give us PDSC problem during CPU reset.

To be more specific, when we use MIMXR1176xxxx_cm7_flexspi_nor.scr, everything is working fine for us. However, as we were to use the MIMXRT1176xxxx_cm7_flexspi_nor_sdram.scr, occasionally it gives us PDSC error, especially if we press CPU reset button.

I read one of the forum and in the forum, a couple of people mentioning having problems when moving the stack and heap to the external SDRAM (ie using MIMXRT1176xxxx_cm7_flexspi_nor_sdram.scr; https://community.nxp.com/t5/i-MX-RT/IMXRT1064-Using-BOARD-SDRAM/m-p/1437072#M18961). 

Questions:

1. Are there any documentation on setting these scatter files when they are being created in the SDK? When to use them and why some of the SDK does not contain all of them?

2. What is the reason why applying  MIMXRT1176xxxx_cm7_flexspi_nor_sdram.scr will cause PDSC failure especially doing a CPU reset? And why is the other one MIMXRT1176xxxx_cm7_flexspi_nor.scr is not having problem?

3. Any other settings we need to concern about when we use these scatter files?

So far, we can only think of this as our studying is still under way. Hope your reply can shed more lights to our finding so far. In the meantime, we do not want to deploy the sdram yet but ultimately we need this being implemented.

Thanks.

[jingpan]

Hi @Desmond_lim ,

1. There isn't documents or guide about these project scatter files and ini files. But in most of demo projects, all these six scatter files can be used.

2. What is the PDSC failure? After reset, SEMC need to be well configured again in order to use SDRAM. SDRAM can be configured by ini file when debug, or configure by ROM bootloader. But that need DCD file in right position.

3. Please refer to AN12107, AN12108, AN12183 .

Regards,

Jing