COFF File Format Replaces COD File Format

Due to the elimination of the COD Format from MPASM ouput, and the use of COFF format instead, new flags have been added to COFF files that are generated by C18 v3.30 and MPASM v5.30. These flags are only recognized by MPLINK v4.30 and above. MPLINK v4.30 and above continue to recognize the old COFF files. However, earlier versions of MPLINK may not recognize new COFF files.

Corrected behavior for programs with no high priority Interrupt Service Routine (ISR) due to removal of the vectors region from linker scripts (BIN18-70)

This note is only applicable to programs with the following characteristics:

1. Explicitly defined low priority ISR and
2. No defined high priority ISR and
3. Has the High priority interrupt enabled (either explicity or by not disabling the default)

In the previous versions of the linker scripts (with the vectors region), no code or data was being placed between the High/Low-priority interrupt vectors. Consequently, with the arrival of a High-priority interrupt, the execution of the program would (erroneously) fall into the low-priority ISR. With the removal of the vectors region from the linker scripts, other data or code may be placed at the addresses between the High and Low priority interrupt vectors. This results in a non-deterministic behavior, upon the arrival of a high priority interrupt for these programs.

MPLINK Linker and MPLAB IDE Compatibilty

Due to a change in COFF file format, MPLAB C18 v3.00 and later will not be compatible with versions of MPLINK Linker prior to v4.00 or versions of the MPLAB IDE prior to v7.21.

MPLINK Linker v4.00 and later will have backward compatibility to earlier versions at the source level only. Any existing object files or libraries compiled with earlier versions of the tools will not link using new versions of the tools. They will need to be recompiled from source.

If the user attempts to use this release with object files or libraries compiled with earlier versions of MPLAB C18, MPLINK Linker, and MPASM Assembler, the error message that will be received will be similar to:

Error - Coff file format for 'C:\mcc18\lib/c018i.o' is out of date.

If the user attempts to use an old version of MPLINK Linker to link object files or libraries compiled with this release, the error message that will be received will be similar to:

Error - Coff file format for 'C:\mcc18\lib/c018i.o' does not appear to be a valid COFF file.

• Early adopter part support has been added. See "Devices" below.



• Old linker scripts will no longer be included in new installations. Only the generic linker scripts will be included. For example, 18F4550.lkr, 18F4550i.lkr, 18F4550_e.lkr and 18F4550i_e.lkr (which would be found under MCC18/lkr for the compiler) will no longer be installed. Instead, only 18F4550_g.lkr will be installed (which can be found under MCC18/bin/LKR for the compiler).
  Note: Installing over an older installation will not remove the old linker scripts, but updates will only be made to the new generic linker scripts.
  
  
• The following beta devices have been renamed from "L" devices to "LF" devices:
  18L13K22 to 18LF13K22
  18L13K50 to 18LF13K50
  18L14K22 to 18LF14K22
  18L14K50 to 18LF14K50
  18L24J11 to 18LF24J11
  18L24J50 to 18LF24J50
  18L25J11 to 18LF25J11
  18L25J50 to 18LF25J50
  18L26J11 to 18LF26J11
  18L26J50 to 18LF26J50
  18L44J11 to 18LF44J11
  18L44J50 to 18LF44J50
  18L45J11 to 18LF45J11
  18L45J50 to 18LF45J50
  18L46J11 to 18LF46J11
  18L46J50 to 18LF46J50
  


Introduced in v4.22 from BIN18-72
Request for new #define and #if/else style directives for linker scripts.

As an extension to the new features implemented for BIN18-72, now MPLINK has made available:
1. /p command-line flag allows the user or IDE to define the part number for the linker. If this flag is used, MPLINK will select the correct generic linker script from the \lkr directory relative to the location of the executable and use it to build the project.
2. /u command-line flag allows the user or IDE to define symbols that will be used by the linker to resolve the conditional directives inside the linker script. For more details on this please refer to the MPASM/MPLINK/MPLIB Users Guide.
3. Customized Linker Scripts:
   1. The existing (old) linker scripts will be removed (in the future) from the distribution tree and only the generic linker scripts will be supported. The existing projects with local linker scripts will continue to work and user can decide if they want to use their local linker script or just eliminate it and let the linker to use the generic one. However, regarding the projects that use the default linker script, we recommend that users move to the new paradigm of not having any linker script.
   2. Customization of linker scripts is no different than before. Users can use their existing linker script or take a generic linker script and apply their modifications, and include it in their project. For more details on how to do this modification please refer to the MPASM/MPLINK/MPLIB Users Guide.
4. Generic Linker Scripts:
   Using the conditional directives, now a single generic linker script, per device, replaces the various existing linker scripts, eliminating the need for an explicit selection of a linker-script inside the MPLAB projects. Through the /p and /u command-line flags, the IDE communicates the part number and different debug and part specific information to MPLINK. Accordingly, MPLINK selects the proper generic linker script and uses it to link the entire project. Any combination of the following build possibilities will automatically be handled without the user needing to worry about linker scripts:
   1. Build for debug or no debug for various debuggers
   2. Build for C or assembly only projects
   3. Build for extended or traditional mode (for PIC18)

10F200       10F202       10F204       10F206
10F220       10F222

12C508       12C508A      12C509       12C509A
12C671       12C672
12CE518      12CE519      12CE673      12CE674
12CR509A
12F1822      12F1840*
12F508       12F509       12F510       12F519
12F520       12F609       12F615       12F617 
12F629       12F635       12F675       12F683
12HV609      12HV615
12LF1822     12LF1840*

14000

16C432       16C433       16C505       16C52
16C54        16C54A       16C54B       16C54C
16C55        16C554       16C557       16C558
16C55A       16C56        16C56A       16C57
16C57C       16C58A       16C58B
16C5X
16C61        16C62        16C620       16C620A
16C621       16C621A      16C622       16C622A
16C62A       16C62B       16C63        16C63A
16C64        16C642       16C64A       16C65
16C65A       16C65B       16C66        16C662
16C67        16C71        16C710       16C711
16C712       16C715       16C716       16C717
16C72        16C72A       16C73        16C73A
16C73B       16C74        16C745
16C74A       16C74B       16C76        16C765
16C77        16C770       16C771       16C773
16C774       16C781       16C782       16C84
16C923       16C924       16C925       16C926
16CE623      16CE624      16CE625
16CR54       16CR54A      16CR54B      16CR54C
16CR56A      16CR57A      16CR57B      16CR57C
16CR58A      16CR58B      16CR62       16CR620A
16CR63       16CR64       16CR65       16CR72
16CR83       16CR84
16CXX
16F1516*     16F1517*     16F1518*     16F1519*
16F1823      16F1824      16F1825      16F1826
16F1827      16F1828      16F1829      16F1933
16F1934      16F1936      16F1937      16F1938 
16F1939      16F1946      16F1947 
16F505       16F506       16F526       16F54
16F57
16F59        16F610       16F616       16F627
16F627A      16F628       16F628A      16F630
16F631       16F636       16F639       16F648A
16F676       16F677       16F684       16F685
16F687       16F688       16F689       16F690
16F707       16F716       16F72        16F720 
16F721       16F722       16F722A      16F723
16F723A 
16F724       16F726       16F727       16F73
16F737       16F74        16F747       16F76
16F767
16F77        16F777       16F785       16F818
16F819       16F83        16F84        16F84A
16F87        16F870       16F871       16F872
16F873       16F873A      16F874       16F874A
16F876       16F876A      16F877       16F877A
16F88        16F882       16F883       16F884
16F886       16F887       16F913       16F914
16F916       16F917       16F946

16LF720      16LF721      16LF722A     16LF723 
16LF1516*    16LF1517*    16LF1518*    16LF1519*
16LF1823     16LF1824     16LF1825     16LF1826
16LF1827     16LF1828     16LF1829 
16LF1933     16LF1934     16LF1936     16LF1937 
16LF1938     16LF1939     16LF1946     16LF1947 
16LF707      16LF722      16LF723      16LF724
16LF726      16LF727

16HV540      16HV610      16HV616      16HV785

17C42        17C42A       17C43        17C44
17C752       17C756       17C756A      17C762
17C766
17CR42       17CR43
17CXX

18C242       18C252       18C442       18C452 
18C601       18C658       18C801       18C858 

18F1220      18F1230      18F1320      18F1330
18F13K22     18F13K50     18F14K22     18F14K50
18F2220      18F2221      18F2320      18F2321      
18F2331      18F23K20     18F23K22     18F2410 
18F242       18F2420      18F2423      18F2431 
18F2439      18F2450      18F2455      18F2458
18F248       18F2480      18F24J10     18F24J11 
18F24J50     18F24K20     18F24K22  
18F2510      18F2515      18F252       18F2520 
18F2523      18F2525      18F2539      18F2550 
18F2553      18F258       18F2580      18F2585 
18F25J10     18F25J11     18F25J50     18F25K20
18F25K22     18F25K80  
18F2610      18F2620      18F2680      18F2682      
18F2685      18F26J11     18F26J13     18F26J50     
18F26J53     18F26K20     18F26K22     18F26K80 
18F27J13     18F27J53 
18F4220      18F4221      18F4320      18F4321
18F43K20     18F4331      18F43K22 
18F4410      18F442       18F4420 
18F4423      18F4431      18F4439      18F4450
18F4455      18F4458      18F448       18F4480 
18F44J10     18F44J11     18F44J50     18F44K20     
18F44K22     18F4510      18F4515 
18F452       18F4520      18F4523      18F4525 
18F4539      18F4550      18F4553      18F458 
18F4580      18F4585      18F45J10     18F45J11 
18F45J50     18F45K20     18F45K22     18F45K80 
18F4610      18F4620      
18F4680      18F4682      18F4685      18F46J11 
18F46J13     18F46J50     18F46J53     18F46K20     
18F46K22     18F46K80 
18F47J13     18F47J53     18F6310      
18F6390      18F6393      18F63J11     18F63J90
18F6410      18F6490      18F6493 
18F64J11     18F64J90     18F6520 
18F6525      18F6527      18F6585      18F65J10 
18F65J11     18F65J15     18F65J50     18F65J90
18F65K22     18F65K80     18F65K90 
18F6620      18F6621      18F6622      18F6627 
18F6628      18F6680      18F66J10     18F66J11
18F66J15     18F66J16     18F66J50     18F66J55
18F66J60     18F66J65     18F66J90     18F66J93 
18F66K22     18F66K80     18F66K90     
18F6720      18F6722      18F6723      18F67J10 
18F67J11     18F67J50     18F67J60     18F67J90 
18F67J93     18F67K22     18F67K90 
18F8310      18F8390      18F8393      18F83J11
18F83J90     18F8410      18F8490 
18F8493      18F84J11     18F84J90
18F8520      18F8525      18F8527      18F8585 
18F85J10     18F85J11     18F85J15     18F85J50
18F85J90     18F85K22     18F85K90     18F8620      
18F8621      18F8622 
18F8627      18F8628      18F8680      18F86J10 
18F86J11     18F86J15     18F86J16     18F86J50
18F86J55     18F86J60     18F86J65     18F86J72 
18F86J90     18F86J93     18F86K22     18F86K27
18F86K90 
18F8720      18F8722      18F8723      18F87J10
18F87J11     18F87J50     18F87J60     18F87J72 
18F87J90     18F87J93     18F87K22     18F87K90 
18F96J60     18F96J65     18F97J60

18LF13K22    18LF13K50    18LF14K22    18LF14K50 
18LF23K22    18LF24J11    18LF24J50    18LF24K22 
18LF25J11    18LF25J50    18LF25K22    18LF25K80*
18LF26J11    18LF26J13    18LF26J50    18LF26J53 
18LF26K22    18LF26K80* 
18LF27J13    18LF27J53    18LF43K22    18LF44J11    
18LF44J50    18LF44K22    18LF45J11    18LF45J50
18LF45K22    18LF45K80*   18LF46J11
18LF46J13    18LF46J50    18LF46J53    18LF46K22 
18LF46K80*   18LF47J13    18LF47J53 
18LF65K80*   18LF66K80*

EEPROM16     EEPROM8

MCV08A       MCV14A       MCV18A       MCV18E
MCV20USB     MCV28A

RF509AF      RF509AG      RF675F       RF675H
RF675K

*Note: Early adopter support has been added for these devices since last release

THE PARTS CORRESPONDING TO THESE OPTIONS MAY NOT ALL BE COMMERCIALLY AVAILABLE.

The part selection is specified at assembly time and contained within the object file. An appropriate linker command file is necessary to properly link for the chosen part.

Windows 2000, Windows XP and 32-bit Windows Vista

(BIN18-3 / 22483)

MPLIB is unable to work with MPLAB C18 files compiled in the static overlay model.
For example, the source code:

        int add( int a, int b )
        {
           int c;
       
           c = a + b;
           return c;
        }

can be compiled and archived with the commands:

        mcc18 test.c -sco
        mplib -c test.lib test.o

However, attempting to list the files in the archive link the archive will result in the error:

        Error - Coff file 'test.o' could not read string table.
        Error - Could not build member 'test.o' in library file './test.lib'.

(BIN18-5 / 3224)

MPLINK Linker always links in the section which loads initialized data from program memory to data memory, even though it is not required.

(BIN18-21 / 18214)

If MPLINK.EXE is invoked without arguments, an error message stating "Error spawning _mplink.exe" is emitted. This message is spurious; it can be ignored.

(BIN18-22 / 18432)

An interrupt with locals of "overlay" storage class which calls a function reachable from main is incorrectly viewed as recursive.
For example, the program:

        int g (void) {
          return 2;
        }

        void f (void);
        #pragma interrupt f
        void f (void) {
          overlay int x;
          x = g ();
        }

        void main (void) {
          int x;
          x = g ();
        }

Will cause a linker error, stating that 'g' is recursive and has locals of "overlay" storage class. The workaround is to use "auto" instead of "overlay" in the interrupt.

(BIN18-26 / 19225)

MPLINK Linker may generate an assertion failure on programs which contain a section of zero length. The workaround is to remove such sections from the program.

(BIN18-27 / 20403)

The '/r' option of MP2HEX does not work correctly for ranges specified outside of any existing data.
For example, given the following source, 't.asm':

        LIST P=12C508
        CODE 0x100
        MOVLW 0
        MOVLW 1
        MOVLW 2
        MOVLW 3
        END

After assembly, execute 'mp2hex.exe t.o /r 0x104-0x104'. The hex file content is:

        :02 0000 04 0000FA
        :02 0206 00 030C E7
        :00 0000 01 FF

The data record shows the instruction 'MOVLW 3' at address 0x103, but 0x103 was not specified in the range.
Since no data exists at 0x104 in the COFF file, there should be no data bytes in the hex file.

(BIN18-29 / 22228)

Quiet mode (/q) disables the printing of errors and warnings to standard out.

(BIN18-33 / 22947)

The /? command-line option may give the following error message on Windows 2000:

        Error - unknown switch: /r

Use the /h option instead.

(BIN18-50 / 27314)

Program memory utilization is not correct in map files generated for PIC18F87J10.

(BIN18-53 / 28114)

The linker may disregard the section information in the last IDATA due to CONFIG syntax directives.