TMS320F28377D: Assembler Help: Reading data on a 32-bit PORT

Hi Peter,

Yes, the IN instruction only works on 16-bit data moves.  To perform a 32-bit read from external memory on this device you'll need to set up an XAR register and do a MOVL into the accumulator.  Something like:

MOV AH, #0x8000
MOV AL, #0x0000
MOVL XAR2, ACC
MOVL ACC, *XAR2

Regards,

Richard

Hi Richard, thank you for this. I thought it could do it but using the IN command.

Can I ask you one more thing. In CCS9 I created a mixed C and assembler project and let C know about the external asm file.

All built fine and downloaded and run on my 28377D.

I've now created a who new CCS project but assembler only and now when I build CCS 9 tells me NO SUITABLE ENTRY POINT - SETTING to 0.

And when I run the assembler program it doesn't run. 

Can you let me know how to set the entry point please. Oh, in assembler. I'm guessing its not .ORG like the old times. LOL.

Thanks Richard, hope to hear from you soon.

Peter

Hi Peter,

No, the good old days have gone.

It's unusual to have an "assembly only" program on this device, but there's no reason why it shouldn't be done.  If you've configured the device to boot into RAM, the PC will go to address 0x00000000.  You'll need to place an LB instruction at that location to branch into wherever your program is.  For example, in your linker file you might have:

MEMORY
{
PAGE 0 :

BEGIN : origin = 0x000000, length = 0x000002

...

}

SECTIONS
{

cstart        : > BEGIN,     PAGE = 0

.text : >> RAMD0 | RAMLS0 | RAMLS1 | RAMLS2 | RAMLS3 | RAMLS4, PAGE = 0

...

}

Then, in your code:

.def _start ; code entry point
.def _c_int00 ; C boot label to avoid linker warning

; branch to start of program: place at boot exit point in .cmd file

.sect "cstart"

_c_int00:

LB _start ; jump to start of program

.text

_start:

; your code starts here
MOV   @SP, #0x0400

...etc.

If you're building for flash you'll need to place cstart into 0x80000.  This seems to work on my LaunchPad - let me know if you run into any difficulty.

Regards,

Richard

Thanks Richard, you're the best. :) 

A while ago I developed a hand held game using the F28377D and in CC6 (I think) it was years ago, had a problem.

I needed to store all the game graphics and sound FX (sampled 8 bit samples) in to the 28377D's flash memory. FLASH B, C, D, E are all 32k in size and when my assembler listing size exceeded 32K the assembler CC6 would NOT write the rest of my code to the other FLASH banks.

The error I was receiving was CODE TO LARGE TO FIT IN TO BANK B and then it would not compile anymore so I was stuck with 32k only.

I was wondering if CC9 has fixed that problem? Would you know? I suppose I could try it myself and see. I will let you know.

Again, thank you so much for your help, it's truly appreciated. 

Pete. :)