Compiler/TMS320F28335: Facing problem while executing from FLASH

Shinto Antony

Part Number: TMS320F28335

Tool/software: TI C/C++ Compiler

I am new to programming, I am trying to test a code in TMS320F28335 experimenter kit,

code contain 3 ISR - timer0 (5s), timer1 (25ms) and SCI

in timer0 --> toggling GPIO31, timer1 --> CpuTimer1.InterruptCount++, In SCI ISR --> if (message[n][index]!= '\0') SciaRegs.SCITXBUF= message[n][index++];

Program run perfectly from RAM, but when I switch to FLASH facing some issues

while(1)
{
SciaRegs.SCITXBUF=message[n][index++];

while(CpuTimer1.InterruptCount < 40)
{

}
index = 0;
CpuTimer1.InterruptCount = 0;
n++;
if(n == SCIMAX) n = 0;
}

While running from FLASH, CpuTimer1.InterruptCount is keep incrementing not resetting after 40, I tried using a another variable instead of CpuTimer1.InterruptCount (which increment in timer ISR and used in while condition) --> working.

What is the issue while using CpuTimer1.InterruptCount

Thanks and regards

Shinto

over 8 years ago

0 Hareesh Janakiraman over 8 years ago

TI__Guru* 95315 points

Do you have any initialized constants in RAM? If so, they would get loaded only when the emulator is connected and the program loaded (but not upon a "cold" power-up). Could you please check your .map file if this is the case? Code working fine in RAM but not in flash is a fairly common issue. This has been addressed many times on the forum before. Please do a search on " works from RAM not flash " or a similar string for helpful threads.

0 Hareesh Janakiraman over 8 years ago in reply to Hareesh Janakiraman

TI__Guru* 95315 points

Here is an excerpt from a reply my colleague posted just a few days back:

"...The golden rule when booting stand-alone is to remember that the program has nothing loaded/initialized in RAM for it to function. Any initialized data in RAM has to be coming from flash and the runtime C libraries will take care of this before program reaches main(). Inspect your map file for all the sections that are being loaded into RAM and see if there are initialized locations for program to function, if yes, then they need to moved to flash into a .cinit section. Similar to the RAMFUNCS sections that the main code does a memcpy, which is for any functions that need to be run from RAM, there will be a copy for the initialized data as well...."

You can read the entire thread at https://e2e.ti.com/support/microcontrollers/c2000/f/171/p/634545/2354353

Like this, there are many threads on the forum that address this exact issue.

0 Hareesh Janakiraman over 8 years ago in reply to Hareesh Janakiraman

TI__Guru* 95315 points

Please refer to http://processors.wiki.ti.com/index.php/C2000_Flash_Common_Issues/FAQs#Running_Code_Standalone

C2000™︎ microcontrollers

C2000 microcontrollers forum

Compiler/TMS320F28335: Facing problem while executing from FLASH