TMS320C6748: Replace running program executing from RAM with another program and continue to execute from RAM.

Hello Tomer,

I don't think this is possible. Is it okay to combine your second program with the first one so that both will be copied to RAM by the bootloader?

Regards,

Jianzhong

Hi,

No. As I wrote, the second program should be sent via serial at any given time, and than should be copied to RAM and execute from the RAM.

I gave it some more thoughts and there might be a way to do it:

1. user UART LLD to copy your led blink program from host to C6748 RAM,

2. once the copying is complete, a UART interrupt can be generated,

3. UART ISR then invokes the led blink program.

Hi

I started with the following. I generated the LedBlink program. I took the data from the MyBlink.bin file and located it (hard coded) in the RAM. The linker  located it automaticaly at some random addess, let's say: 0x12345678. Now I want to generated some trigger or write som command (jump, branch...) that will go to this address and start running what in it, that is my LedBlink program.
Is that making sense? Is it possible? What is the sintax of such a jump command? I tried some options but the compiier didn't liked it...

Try the assembly branch instruction. Take a look at the TMS320C674x DSP CPU and Instruction Set https://www.ti.com/lit/sprufe8. 

I think I have a direction now...
Till now I used the AISgen tool to generate the boot image in AIS format. This format is probably not good for me. It inclueds header and AIS commands that are good for TI's bootloader but not good when I try to jump to the address in RAM in which I located the content of this ais format file. I think I should use another way to generate the binary code of the LedBlink program. Can you approve my understanding?

Don't you need AIS format to flash the program?

No. I don't need to flash the LedBlink program at all. As I wrote, I am trying to locate the code of the LedBlink program in the RAM and then jump to this code and execute from RAM...   

Ok. Thanks for explanation. Your understanding is correct.

I found the C6000 Hex Utility. With this utility I am now being able to get an .hex file. I am tring now to figure out how should I build this .hex file in order to be able to copy it to RAM and be able to execte from it. Can you assist with a simple example or can you refer me to someone who can help? 

Would what I recommended earlier work?

1. user UART LLD to copy your led blink program from host to C6748 RAM,

2. once the copying is complete, a UART interrupt can be generated,

3. UART ISR then jumps to the location where your led blink program is copied.

Did not tried it since I am encountering some more basic isses:
1) I don't understand yet how should I build the LedBlink program? Using the AIS tool to create .bin file? Using the C6000 hex utilitiy to create .hex file? 

2) Should the host send  the all program to C6748 or should it remove some header?

3) I don't know how to generate the interrupt and how to cause the ISR jump to the location the LedBlink was copied.

I assume using the UART is just a way to transfer the LedBlink program from hot to RAM.

I skipped this stage and directly (hard coded) copy the LedBlink program to the RAM in a specific location.

I am running from the debugger and generated a trigger (setting a flag to TRUE) to do this:

@define GO(addr) { ((void(*)(void)(addr))(); }

if(flag == TRUE)

{

GO(0x12345678); //the address where I copied my LedBlink code

}

hoping it will jump to my LedBlink code and execute it, but I am getting an exception....

You can write your isr in assembly code and use the branch instruction. Please refer to the TMS320C674x DSP CPU and Instruction Set Reference Guide.