Accessing EEPROM with Cosmic compiler

[jark]

Posted on July 26, 2010 at 20:46

Accessing EEPROM with Cosmic compiler

[luca239955_stm1_st]

Posted on May 17, 2011 at 15:09

Hi,

there's no need for include files, but you must define a .eeprom segment in the linker file (I'm not sure if STVD does that automatically).

What linker error do you have exactly?

Regards,

Luca

[jark]

Posted on May 17, 2011 at 15:09

Hi,

    Thanks for the quick response.  The error message I get is:

#error clnk Debug\lc_meter_v1.lkf:1 bad address (0x4000) for zero page symbol _Cstd

 The command: ''clnk -l''C:\Program Files\COSMIC\CXSTM8_16K\Lib''  -o Debug\lc_meter_v1.sm8 -l..\..\..\..\libraries\stm8s_stdperiph_driver -mDebug\lc_meter_v1.map Debug\lc_meter_v1.lkf '' has failed, the returned value is: 1

exit code=1.

    Thanks,

    Jim

[luca239955_stm1_st]

Posted on May 17, 2011 at 15:09

looks like something is wrong with your linker file, please post it.

[jark]

Posted on May 17, 2011 at 15:09

OK - here's the file

# LINK COMMAND FILE AUTOMATICALLY GENERATED BY STVD: TOTALLY

# IF AUTO MODE IS ENABLED, OR ONLY PARTIALLY WHEN AUTO MODE

# IS DISABLED (see below).

#

# CAUTION:

#

# Sections delimited by <BEGIN ...> and <END ...> markers are

# reserved for STVD: DO NOT MODIFY INSIDE.

#

# Manual modifications are allowed OUTSIDE these sections, WHEN

# STVD ''auto'' MODE IS DISABLED (if ''auto'' mode is enabled,

# modifications are lost).

# When STVD ''auto'' mode is disabled, it is also possible to disable

# the automatic update inside the reserved sections, by removing the

# <BEGIN ...> and <END ...> markers of the corresponding section.

#

# Please refer to Cosmic User Manuals before any modification.

# Note that errors in editing this file may have unpredictable results

# when running STVD.

# Segment configuration - section reserved for STVD

#<BEGIN SEGMENT_CONF>

# Segment Code,Constants:

+seg .const -b 0x8080 -m 0x7f80 -n .const -it

+seg .text -a .const -n .text

# Segment Eeprom:

+seg .eeprom -b 0x4000 -m 0x400 -n .eeprom

# Segment Zero Page:

+seg .bsct -b 0x0 -m 0x100 -n .bsct

+seg .ubsct -a .bsct -n .ubsct

+seg .bit -a .ubsct -n .bit -id

+seg .share -a .bit -n .share -is

# Segment Ram:

+seg .data -b 0x100 -m 0x500 -n .data

+seg .bss -a .data -n .bss

#<END SEGMENT_CONF>

# Startup file - section reserved for STVD

#<BEGIN STARTUP_FILE>

crtsi0.sm8

#<END STARTUP_FILE>

# Object files list - section reserved for STVD

#<BEGIN OBJECT_FILES>

Debug\stm8s_clk.o

Debug\stm8s_gpio.o

Debug\stm8s_itc.o

Debug\main.o

Debug\stm8_interrupt.o

Debug\stm8s_adc1.o

Debug\stm8s_beep.o

Debug\stm8s_exti.o

Debug\stm8s_lcd.o

Debug\stm8s_tim1.o

Debug\stm8s_tim2.o

Debug\stm8s_tim3.o

Debug\stm8s_tim4.o

Debug\timers.o

Debug\utilities.o

#<END OBJECT_FILES>

# Library list - section reserved for STVD

#<BEGIN LIBRARY_FILES>

libfs0.sm8

libis0.sm8

libm0.sm8

#<END LIBRARY_FILES>

# Interrupt vectors file - section reserved for STVD

#<BEGIN VECTOR_FILE>

+seg .const -b 0x8000 -k

Debug\stm8_interrupt_vector.o

#<END VECTOR_FILE>

# Defines - section reserved for STVD

#<BEGIN DEFINED_VARIABLES>

+def __endzp=@.ubsct            # end of uninitialized zpage

+def __memory=@.bss                # end of bss segment

+def __startmem=@.bss

+def __endmem=0x5ff

+def __stack=0x7ff

#<END DEFINED_VARIABLES>

[jark]

Posted on May 17, 2011 at 15:09

Hi,

   I may have found the problem.  I used Cstd in both the main.c module and also in another module of the program.  There, I referred to it as:

extern float Cstd;

If I referred to it as 'extern @eeprom float Cstd', I got an error; I did not get an error if I referred to it as shown above.

    I only used it in one procedure there and have just found that, if I move that procedure into my main.c module where I declare all the variables, I no longer get a clink error.  I have yet to determine if I can properly access Cstd in the program.  It is only written to in a calibration procedure which is only used infrequently - but it is read in many different places in the project.

[luca239955_stm1_st]

Posted on May 17, 2011 at 15:09

the linker file looks correct, so that's not yet enough information to understand the problem..

This symbol that is giving the error ''Cstd'', is that something you defined?

Can I see the definition ? Or you can post the entire project of it not confidential

[jark]

Posted on May 17, 2011 at 15:09

There's nothing confidential about the project but it is, I think, too long to post

the whole thing.  The section where I define the variables is:

// global variables follow

enum menu_t menu_mode;

enum meas_t measurement_mode;

float Cstd = 469.0e-12;

float C1 = 509.0e-12;

float L68 = 67.0e-6;

float L1 = 68.0e-6;

float Cx, Lx;

long f1, f2;

u8 s[16];

float rho;

char cont;

As above, it compiles, links and runs correctly.  I get the clink error when I change the line with Cstd in it to the following:

@eeprom float Cstd = 469.0e-12;

    Jim

[jark]

Posted on May 17, 2011 at 15:09

Hi again,  OK, it compiles without errors and the program can read the value of Cstd when it is declared:

@eeprom float Cstd = 469.0e-12;

It is read frequently in the program.  However, in a calibration routine, if I try to change it with a statement like:

    Cstd = Cstd * 0.998;

it does not change - I read it a few lines later and it has just got the same value as initialized in the statement which defines the variable.

    Jim

[jark]

Posted on May 17, 2011 at 15:09

 Hi,

    I've looked at the assembler code produced by the compiler for the brief code; it looks fine to me but it illustrates the problem.

 352                     ; 187                                                        Cstd = Cstd * factor;

 354  0141 ae0000            ldw    x,#_Cstd

 355  0144 cd0000            call    c_ltor

 357  0147 ae0075            ldw    x,#L531

 358  014a cd0000            call    c_fmul

 360  014d ae0000            ldw    x,#_Cstd

 361  0150 cd0000            call    c_eewrl

 

It looks like it reads the eeprom, does the multiplication and then tries to store it

back in eeprom with the call to c_eewrl.  However, when I run the program, the value in Cstd is NOT changed.

   Anyone have any suggestions?

   Jim

[jark]

Posted on May 17, 2011 at 15:09

Hi,

    The problem was that I was not 'unlocking' the EEPROM before writing to it.  I needed to #include the stm8s_flash.h file at the beginning and then the code to write to the eeprom looked like:

    .......

    FLASH_Unlock(FLASH_MEMTYPE_DATA);

    Cstd = Cstd *factor;

    FLASH_Lock(FLASH_MEMTYPE_DATA);

    ..........

where Cstd is the variable in eeprom.