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Problem using xdata

I am trying to compile a C code using Keil uvision 3. The entire code gets compiled only if I use large memory model by choosing option xdata for target. To use this model I have to use external data RAM which is not possible for me due to some reasons. So I decided to go with pdata option. Can anybody please help me with the exact steps to be carried out for using pdata? I am using 89V51RD2. I am much confused with the options like BL51 MISC, BL51 Locate etc.

  • The entire code gets compiled only if I use large memory model
    wrong approach, allocate a sufficient number of (rarely used) variables to xdata/pdata and stay in the small model.

    To use this model I have to use external data RAM which is not possible for me due to some reasons. So I decided to go with pdata option.
    If you can not get by with the anount of internal XRAM the chip has, you are lost anyhow.
    The amount of XRAM (internal or external) is the same whether you use XDATA or PDATA

    Erik