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Defining Heap Segment in external ram in IAR M32c Renesas

Discussion in 'Embedded' started by srikanthn, Nov 5, 2007.

  1. srikanthn

    srikanthn Guest

    For my application purpose i used an external 128k Sram to M30845fjg
    renesas m32c controller.

    I modified the linker file by defining the heap sizes in externa
    addresses, but i was unable to have the heap segment.

    when iam placing data in ex-ram it was getting read, but the heap is no
    going to allocate even though the map file is locating the heap ranges.

    can u help me to get out of this.
     
    srikanthn, Nov 5, 2007
    #1
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  2. srikanthn

    srikanthn Guest

    For my application purpose i used an external 128k Sram to M30845fjgp
     
    srikanthn, Nov 6, 2007
    #2
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  3. Due to some problem, My reply has not got posted.
    I am posting it onceagain.

    Check the following :
    1) Memory Overlap in the Linker Script / Linker Command File.
    2) Proper invokation of Heap Memory Allocation w.r.t linker script.
    See, if you are allocating within the defined range.
    3) Even though you have allocated the Heap memory correctly by
    directing it to refer to the external memory, Did you check if the
    external memory is operational / enabled at the time of
    allocation ?
    4) Proper chip-selects for the external SRAM memory.
    5) Do a basic sanity check of your external SRAM to find if it is
    working
    properly.
    a) Data bus wiring check ( test the bus one bit at a time. The data
    bus passes the test if each data bit can be set to 0 and 1,
    independently of the other data bits.)
    that is , Walking 1's test.
    b) Address Bus check - Perform read/write similar to data bus check
    - can try with "power-of-two" addresses read/write to check every bit
    Write to one of the addresses and check if there is any
    overwriting in other address .

    Karthik Balaguru
     
    karthikbalaguru, Nov 6, 2007
    #3
  4. Also , Take care of the influence(Re-Mapping/Address Shifting) due to
    MMU (If you use MMU).

    Karthik Balaguru
     
    karthikbalaguru, Nov 6, 2007
    #4
  5. Check the following :
    1) Memory Overlap in the Linker Script / Linker Command File.
    2) Proper invokation of Heap Memory Allocation w.r.t linker script.
    See, if you are allocating within the defined range.
    3) Even though you have allocated the Heap memory correctly by
    directing it to refer to the external memory, Did you check if the
    external memory is operational / enabled at the time of
    allocation ?
    4) Proper chip-selects for the external SRAM memory.
    5) Do a basic sanity check of your external SRAM to find if it is
    working
    properly.
    a) Data bus wiring check ( test the bus one bit at a time. The data
    bus passes the test if each data bit can be set to 0 and 1,
    independently of the other data bits.)
    that is , Walking 1's test.
    b) Address Bus check - Perform read/write similar to data bus check
    - can try with "power-of-two" addresses read/write to check every bit
    Write to one of the addresses and check if there is any
    overwriting in other address .

    Karthik Balaguru
     
    karthikbalaguru, Nov 7, 2007
    #5

  6. Appologies.
    I wonder why this message appears very late.
    Refer my earlier post in this same thread in which i have mentioned as
    below -
    " Due to some problem, My reply has not got posted.
    I am posting it onceagain. "

    Strange, but how did the above message(re-post) got posted and this
    message(original message) arrives after that ? Actually this
    message(Original message)
    was posted before that message(re-post) !!! :(:(.
    Strange :(:(:( !!!!

    Karthik Balaguru
     
    karthikbalaguru, Nov 7, 2007
    #6
  7. srikanthn

    srikanthn Guest

    First of all thanking for ur valueable reply, i tried ur suggestions bu
    still no change in the problem.
    mode 0, with seperate bus.

    Regards srikanthn
     
    srikanthn, Nov 12, 2007
    #7
  8. Ok. Is the Memory Read and Write operation possible in the allocation
    region.
    If you are using your own allocation routine. Then, modify it to
    read and print the data from the region or write some data into the
    region
    and read-back with delay before allocation.

    ..>> 4) no chip-selects iam using for the external SRAM memory, iam
    using
    Ok. Thats fine.

    Did you try those, Walking 1s , Basic Sanity checks,
    Address Bus , Data Bus checks w.r.t SRAM ?

    Karthik Balaguru
     
    karthikbalaguru, Nov 12, 2007
    #8
  9. Do you use MMU ?

    Kawrthik Balaguru
     
    karthikbalaguru, Nov 16, 2007
    #9
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