Original question:
Tool/software:
#1. Customer wants to develop AM62x R5F with EB Autosar, Would like to get farmilar with AM62x MCU SDK by themselves in advance, especially with R5F, how to start it? It is noted R5 can't be loaded, but there is R5F hello world example.
#2. Board is init with NULL SBL already, which core is NULL SBL runing on? R5 only?
#1. For a R5F application, just need to add a extra thread like the hello world example to call below two routine?
/* Init LPM specific data */ Sciclient_initDeviceManagerLPMData(&gDMLPMData); sciServer_init();
#2. Will it start sciServer and keep running? is it just a one time call then was deleted in this example?
#3. What does SBL NULL done? load TIFS? and start R5F sci sever? and else?
Hello Tony,
On DM R5F core (AM62x), when we issue a CPU reset via CCS, the TCM address map changes — now TCMB is at 0x00000000.
If you then load an .out file built to assume vector table at TCMA (0x0), it crashes, because 0x0 is no longer valid for that code path.
Correct Methods to Solve This
Method 1: Load to 0x0 (TCM), then set PC to 0x0
• If you load the .out image from CCS , the first we need to change MMR setting default to TCMA memory .
Next , point the PC to 0x0 and load an .out file .
Method 2 (Recommended): Place vector table in DDR (like SDL examples do)
• This avoids TCM mapping issues.
• Vector table is placed in a fixed location in DDR (e.g., 0x80000000).
• The R5 vector base address (VBAR) is programmed to point to that DDR location in startup.
• You can load .out directly from CCS, even after CPU reset.
Please follow the Method 2
This avoids TCM mapping issues after CPU reset, and makes your .out CCS loadable and remove unnecessary SDL .c files in the application and integrate what ever files needed to Test the application .
Regards,
Anil.
Hello Anil,
Method 2 (Recommended): Place vector table in DDR (like SDL examples do)
• This avoids TCM mapping issues.
• Vector table is placed in a fixed location in DDR (e.g., 0x80000000).
• The R5 vector base address (VBAR) is programmed to point to that DDR location in startup.
• You can load .out directly from CCS, even after CPU reset.
That is my question here,Debug the board according to Method 2，The program cannot start executing from the main function. The code keeps getting stuck at the "lpm_clear_all_wakeup_interrupt()" function.
1、Which core is running?
2、Why and how to solve this problem？
Hi Anil,
C:\ti\mcu_plus_sdk_am62x_11_00_00_16\examples\sdl\ecc\am62x-sk\r5fss0-0_nortos\ti-arm-clang can run by reset cpu before download .out.
but hello world can't run.
compared the map file, the hello world example uses TDMA and TCMB, the ecc example usesTCMA only.
In hello world example cmd file, there are many memory allocation as below:
load = R5F_TCMB, run = R5F_TCMA
Why load to TCMB, run in TCMA?
Replace the hello world project link.cmd with that of ecc_app example, rebuild and can run.
Hi Anil,
#1. Why swap ATCM and BTCM, what is purpose and benefit? who will trigger the space swap at which point?
#2. For a real use case which should work together with DM like the sbl_null, it doesn't use ATCB or BTCM memory at all.
