MSP430G2755: Issue when moving/changing start address using linker command file

The linker script for the application should tell the linker where to place .text sections. Your script fragment tells it where to put .boot segments. Not in a memory location but in some other named segment. Not sure if that works.

An odd name for an application segment but not awful for the bootloader.

My experience is with the GCC linker but from what I can see, the linker scripts are very similar if not identical. "info ld" is where I look first for information on that.

To locate the application/boot loader I would alter the ROM size/location. The linker would then handle the job of locating .text (and other read only) sections there.

With C code at least the beginning of the ROM image is not always, or even frequently the location where execution starts. Most often read only data for variable initializers and such goes here. You have to examine the contents of the reset vector (in its very own 2 byte section) to find that. Which makes writing a boot loader extra tricky.

I cannot find a way to attached a file to the forum which would be cleaner than pasting too much text into a post.

I think TI used to allow attaching a file to the forum?

Anyway, I guess I will need to paste the text here.

Here is my linker command file.

MEMORY
{
SFR : origin = 0x0000, length = 0x0010
PERIPHERALS_8BIT : origin = 0x0010, length = 0x00F0
PERIPHERALS_16BIT : origin = 0x0100, length = 0x0100
RAM_VECTORS : origin = 0x1100, length = 0x0080
RAM : origin = 0x1180, length = 0x0F78
INFOA : origin = 0x10C0, length = 0x0040
INFOB : origin = 0x1080, length = 0x0040
INFOC : origin = 0x1040, length = 0x0040
INFOD : origin = 0x1000, length = 0x0040
FLASH : origin = 0x8000, length = 0x5FE0
FLASH_APPSWVER : origin = 0xDFE0, length = 0x0010
FLASH_APPXSUM : origin = 0xDFF0, length = 0x0010
FLASH_BOOTLOADER : origin = 0xE000, length = 0x1FE0
FLASH_VECTORS : origin = 0xFFE0, length = 0x001E
RESET : origin = 0xFFFE, length = 0x0002

/*--------------------------------------------------------
Forcing vectors, EXCEPT for RESET, to point to RAM
addresses using FLASH_VECTORS & FLASHVECT_SEG. Not using
default dynamic linking to functions. Original
implementation saved here for reference.

INT00 : origin = 0xFFE0, length = 0x0002
INT01 : origin = 0xFFE2, length = 0x0002
INT02 : origin = 0xFFE4, length = 0x0002
INT03 : origin = 0xFFE6, length = 0x0002
INT04 : origin = 0xFFE8, length = 0x0002
INT05 : origin = 0xFFEA, length = 0x0002
INT06 : origin = 0xFFEC, length = 0x0002
INT07 : origin = 0xFFEE, length = 0x0002
INT08 : origin = 0xFFF0, length = 0x0002
INT09 : origin = 0xFFF2, length = 0x0002
INT10 : origin = 0xFFF4, length = 0x0002
INT11 : origin = 0xFFF6, length = 0x0002
INT12 : origin = 0xFFF8, length = 0x0002
INT13 : origin = 0xFFFA, length = 0x0002
INT14 : origin = 0xFFFC, length = 0x0002
---------------------------------------------------------*/
}

/****************************************************************************/
/* SPECIFY THE SECTIONS ALLOCATION INTO MEMORY */
/****************************************************************************/

SECTIONS
{
.bss : {} > RAM /* GLOBAL & STATIC VARS */
.data : {} > RAM /* GLOBAL & STATIC VARS */
.sysmem : {} > RAM /* DYNAMIC MEMORY ALLOCATION AREA */
.stack : {} > RAM (HIGH) /* SOFTWARE SYSTEM STACK */

.boot > 0x8000
{
-l rts*.lib<boot_special.obj > (.text)
}

GROUP
{
.text : {} /* CODE */
.cinit : {} /* INITIALIZATION TABLES */
.const : {} /* CONSTANT DATA */

.pinit : {} /* C++ CONSTRUCTOR TABLES */
.init_array : {} /* C++ CONSTRUCTOR TABLES */
.mspabi.exidx : {} /* C++ CONSTRUCTOR TABLES */
.mspabi.extab : {} /* C++ CONSTRUCTOR TABLES */
} load = FLASH

/*---[RUN FROM RAM]----------------------------------------*/
RAMVECT_SEG : load = FLASH, run = RAM_VECTORS, table(_ramvector)
.ovly : {} > FLASH

/*---------------------------------------------------------*/
.infoA : {} > INFOA /* MSP430 INFO FLASH MEMORY SEGMENTS */
.infoB : {} > INFOB
.infoC : {} > INFOC
.infoD : {} > INFOD

.cio : {} > RAM /* C I/O BUFFER */
.reset : {} > RESET
FLASHVECT_SEG : {} > FLASH_VECTORS
APPSWVER_SEG : {} > FLASH_APPSWVER

/**** MSP430 INTERRUPT VECTORS ****/
/*--------------------------------------------------------
Forcing vectors, EXCEPT for RESET, to point to RAM
addresses using FLASH_VECTORS & FLASHVECT_SEG. Not using
default dynamic linking to functions. Original
implementation saved here for reference.

TIMER1_A1 : { * ( .int00 ) } > INT00 type = VECT_INIT
TIMER1_A0 : { * ( .int01 ) } > INT01 type = VECT_INIT
PORT1 : { * ( .int02 ) } > INT02 type = VECT_INIT
PORT2 : { * ( .int03 ) } > INT03 type = VECT_INIT
TRAPINT : { * ( .int04 ) } > INT04 type = VECT_INIT
ADC10 : { * ( .int05 ) } > INT05 type = VECT_INIT
USCIAB0TX : { * ( .int06 ) } > INT06 type = VECT_INIT
USCIAB0RX : { * ( .int07 ) } > INT07 type = VECT_INIT
TIMER0_A1 : { * ( .int08 ) } > INT08 type = VECT_INIT
TIMER0_A0 : { * ( .int09 ) } > INT09 type = VECT_INIT
WDT : { * ( .int10 ) } > INT10 type = VECT_INIT
COMPARATORA : { * ( .int11 ) } > INT11 type = VECT_INIT
TIMERB1 : { * ( .int12 ) } > INT12 type = VECT_INIT
TIMERB0 : { * ( .int13 ) } > INT13 type = VECT_INIT
NMI : { * ( .int14 ) } > INT14 type = VECT_INIT
---------------------------------------------------------*/
}

/****************************************************************************/
/* INCLUDE PERIPHERALS MEMORY MAP */
/****************************************************************************/

-l msp430g2755.cmd

Use the "Insert" button and select "Code". This creates a scrollable window for long bits of code. Or linker scripts.

Not that the complete script illuminated anything.

I noticed that there is a linker warning:

<Linking>
"../lnk_msp430g2755.cmd", line 108: warning #10068-D: no matching section
warning #10229-D: output section ".data" refers to load symbol "$C$SL1" and hence cannot be compressed; compression "lzss" is ignored
Finished building target: "abc.out"

The line 108 is this line

-l rts*.lib<boot_special.obj > (.text)

boot_special.com is located here:

C:\ti\ccs1120\ccs\tools\compiler\ti-cgt-msp430_16.9.2.LTS\lib\src\boot_special.c

It does not have a SECTION declaration in the C-file that I see. The C-file does have #pragma CLINK(xxxxx).

I searched through "SLAU132Y – MSP430 Optimizing C/C++ Compiler v21.6.0.LTS"  and found no information about "CLINK". Really?!?!?

So,  a few questions:

* What the heck is #pragma CLINK?

   -- Where is it documented?

* How do I force the "boot_special" to 0x8000 if there is no SECTION name of .boot?

   -- What is the proper syntax to accomplish this?

This doesn't solve your original problem, but maybe it provides a helpful clue. It looks like your referencing documentation for a different compiler version than what the boot_special.c file is based on. The path you listed shows that the file is part of the v16.9.2.LTS compiler, but you're referencing the user's guide for the v21.6.0.LTS compiler.  

I also see that CLINK pragma is related to COFF object file format and this format has been deprecated from the latest MSP430 codgen tools. There is a note about that in the revision history of the MSP430 Compiler User's Guide you referenced: SLAU132Y

You can read about the CLINK pragma in the older doc revision that corresponds to v16.9.2.LTS: SLAU132M

Thanks for the info on CLINK. I'll look at some older docs just for curiosity.

As far as compilers (it's long read above), I mentioned that I moved from 16.9.2.LTS to 21.6.0LTS, And, yeah, I agree. I think it is related to that.

I have been looking around and found that

* compiler 21.6.0.LTS declares _c_int00..... in boot.c

* compiler 16.9.2.LTS declares _c_int00..... in boot_special.c

* See attached text file.....

I search for the term "boot" in the .map file and got these results:

26 9: FLASH_BOOTLOADER 0000e000 00001fe0 00000000 00001fe0 RWIX
64 62: 00002030 00000002 rts430_eabi.lib : boot.c.obj (.stack)
101 60: 00009604 00000040 main.obj (.text:BootDelay)
136 62: 00009c0c 0000001c rts430_eabi.lib : boot.c.obj (.text:_c_int00_noargs)
216 62: 0000fffe 00000002 rts430_eabi.lib : boot.c.obj (.reset)
258 8: boot.c.obj 28 2 0
Total found: 6

I tried the various incarnations and still always get a "section not found" warning

"../lnk_msp430g2755.cmd", line 108: warning #10068-D: no matching section
rts*.lib<boot.obj> (.text:_c_int00_noargs)

I hate to do it but I have to go back to the older compiler. I'm sure this can be done with the newer compiler but the linker command file syntax is elusive.

C:\ti\ccs1120\ccs\tools\compiler\ti-cgt-msp430_16.9.2.LTS\lib\src\boot_special.c 9 KB C File 2/24/2017 5:22:47 PM 11/30/2023 11:21:19 AM 12/1/2023 5:02:09 PM 18
56 #pragma CLINK(_c_int00_noargs)
57 CSTART_DECL _c_int00_noargs()
69 #pragma CLINK(_c_int00_noexit)
70 CSTART_DECL _c_int00_noexit()
83 #pragma CLINK(_c_int00_noinit_noargs_noexit)
84 CSTART_DECL _c_int00_noinit_noargs_noexit()
97 #pragma CLINK(_c_int00_noargs_noexit)
98 CSTART_DECL _c_int00_noargs_noexit()
110 #pragma CLINK(_c_int00_mpu)
111 CSTART_DECL _c_int00_mpu()
125 #pragma CLINK(_c_int00_noargs_mpu)
126 CSTART_DECL _c_int00_noargs_mpu()
141 #pragma CLINK(_c_int00_noexit_mpu)
142 CSTART_DECL _c_int00_noexit_mpu()
158 #pragma CLINK(_c_int00_noinit_noargs_noexit_mpu)
159 CSTART_DECL _c_int00_noinit_noargs_noexit_mpu()
175 #pragma CLINK(_c_int00_noargs_noexit_mpu)
176 CSTART_DECL _c_int00_noargs_noexit_mpu()

C:\ti\ccs1120\ccs\tools\compiler\ti-cgt-msp430_21.6.0.LTS\lib\src\boot.c 7 KB C File 5/27/2021 11:40:39 PM 8/7/2022 2:12:43 PM 12/1/2023 5:28:48 PM 16
97 void _c_int00_template(int NEEDS_ARGS, int NEEDS_INIT, int NEEDS_MPU)
130    _c_int00_template(1, 1, 0);
133 CSTART_DECL _c_int00_noargs(void)
135    _c_int00_template(0, 1, 0);
138 CSTART_DECL _c_int00_noinit(void)
140    _c_int00_template(1, 0, 0);
143 CSTART_DECL _c_int00_noinit_noargs(void)
145    _c_int00_template(0, 0, 0);
148 CSTART_DECL _c_int00_mpu(void)
150    _c_int00_template(1, 1, 1);
153 CSTART_DECL _c_int00_noargs_mpu(void)
155    _c_int00_template(0, 1, 1);
158 CSTART_DECL _c_int00_noinit_mpu(void)
160    _c_int00_template(1, 0, 1);
163 CSTART_DECL _c_int00_noinit_noargs_mpu(void)
165    _c_int00_template(0, 0, 1);