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How do pointers with different store type be organized into RAM?

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Read-Only Author HongJi Zhou Posted 30-Nov-2000 03:00 GMT Toolset C51	How do pointers with different store type be organized into RAM? HongJi Zhou As we know, most of pointers in 8051 have 3 bytes. One of these bytes indicates the address type(data, xdata and so on) this pointer points to; the other two bytes will be organized the address. But orders of these 3 bytes are different from the other(with different store type). I want to get the specification. Who can help me? Thanks a lot.

Read-Only Author Andrew Neil Posted 30-Nov-2000 10:38 GMT Toolset C51	RE: How do pointers with different store type be organized into RAM? Andrew Neil The 3-byte pointers are known as "Generic Pointers" It's all in the Manual. Quoting from the C51 User's Guide 03.2000, p81: "Generic pointers are always stored using three bytes. The first byte is for the memory type, the second is for the high-order byte of the offset, and the third is for the low-order byte of the offset." See the table in the Manual for the memory-type byte values and their associated memory types. NB: You can save the overhead of that 3rd, memory-type, byte by using "Memory-Specific" pointers. See the manual (which is on the CD, which is free!)