The code is correct, it's caused by clocks. I can see that you are using clock option A. In this case, it's necessary to program new DCF record to UTEST to change HSE_CLK_MODE_AND_GSKT_CTRL. This will ensure that internal clocks are correctly synchronized.
You can find file S32K3xx_DCF_clients.xlxs in S32K3 reference manual.
And you can find there that dcf_client_utest_misc contains HSE_CLK_MODE_AND_GSKT_CTRL which can have following values:
So, it must be set to 1x. It is not default value, so we need to reprogram it.
Here is a screenshot from my debugger where I already added new DCF record:
The yellow record is original record programmed in factory. I programmed new record (in red) on first available address where I changed HSE_CLK_MODE_AND_GSKT_CTRL accordingly. And then the RNG service works as expected.
You can use attached script to program the record. Just check if 0x1B000770 is first available position in your UTEST.
Or next option is to program the record by your application.
Regards,
Lukas
I tested it in very minimalist and quick way without any project, just by using a debugger.
I simply created own descriptor (hseSrvDescriptor_t) in RAM memory like this:
First word 0x300 is ID of HSE_SRV_ID_GET_RANDOM_NUM, second word is reserved and then there's hseGetRandomNumSrv_t structure. You can take a look at HSE service API reference manual. First word selects DRG3 class, second word selects length of random number (16 bytes) and last word sets pointer where HSE will write the random number.
Then I trigger the service by writing address of the descriptor (0x20400000) to transmit register TR[1] in MU_0. The result is that receive register RR[1] contains return value from HSE 0x55A5AA33 which is HSE_SRV_RSP_OK (operation was successful) and random number is available at 0x2040050:
So, I'm sure the HSE_SRV_ID_GET_RANDOM_NUM works as expected regardless of drivers, software, etc.
The data cache must be disabled for this test, of course.
Regards,
Lukas
The code is correct, it's caused by clocks. I can see that you are using clock option A. In this case, it's necessary to program new DCF record to UTEST to change HSE_CLK_MODE_AND_GSKT_CTRL. This will ensure that internal clocks are correctly synchronized.
You can find file S32K3xx_DCF_clients.xlxs in S32K3 reference manual.
And you can find there that dcf_client_utest_misc contains HSE_CLK_MODE_AND_GSKT_CTRL which can have following values:
So, it must be set to 1x. It is not default value, so we need to reprogram it.
Here is a screenshot from my debugger where I already added new DCF record:
The yellow record is original record programmed in factory. I programmed new record (in red) on first available address where I changed HSE_CLK_MODE_AND_GSKT_CTRL accordingly. And then the RNG service works as expected.
You can use attached script to program the record. Just check if 0x1B000770 is first available position in your UTEST.
Or next option is to program the record by your application.
Regards,
Lukas
It's not needed in case of clock option A on S32K358 because it is default state:
Regards,
Lukas
