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I am an assembly newbie and I am trying to write an assembly routine to write data to EEPROM of a 8051 variant. (Specifically, AT89C51CC03)

In the datasheet, it says that I need to write to the column latches first. For this, I need to fill DPTR register with the address I want to write (2 bytes). As I am working mainly with C, I needed a way to pass the address from C code to the assembly routine. The following link explains the convention:

http://www.keil.com/support/man/docs/c51/c51_ap_parampassreg.htm

which says that pointer parameters are assigned to R2(MSB) and R1(LSB).

My question is, how can I move the contents of these 1 byte registers to DPTR, which is a two byte register? I have a feeling that if I use MOV, I will overwrite the first byte I have written. And the instruction set manual only provides an example for passing immediate values, not from registers.

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It seems they're Special Function Registers (SFRs) called DPH and DPL, which should be accessible in 8-bit mode, see here and here (starting page 20).

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