UPSD3422_06 Datasheet, PDF (38/293 Pages) STMicroelectronics – Turbo Plus Series Fast Turbo 8032 MCU with USB and Programmable Logic

8032 addressing modes
9
8032 addressing modes
uPSD34xx
The 8032 MCU uses 11 different addressing modes listed below:
● Register
● Direct
● Register Indirect
● Immediate
● External Direct
● External Indirect
● Indexed
● Relative
● Absolute
● Long
● Bit
9.1
Register Addressing
This mode uses the contents of one of the registers R0 - R7 (selected by the last three bits
in the instruction opcode) as the operand source or destination. This mode is very efficient
since an additional instruction byte is not needed to identify the operand. For example:
MOV A, R7
; Move contents of R7 to accumulator
9.2
Direct Addressing
This mode uses an 8-bit address, which is contained in the second byte of the instruction, to
directly address an operand which resides in either 8032 DATA SRAM (internal address
range 00h-07Fh) or resides in 8032 SFR (internal address range 80h-FFh). This mode is
quite fast since the range limit is 256 bytes of internal 8032 SRAM. For example:
MOV A, 40h
; Move contents of DATA SRAM
; at location 40h into the accumulator
9.3
Register Indirect Addressing
This mode uses an 8-bit address contained in either Register R0 or R1 to indirectly address
an operand which resides in 8032 IDATA SRAM (internal address range 80h-FFh). Although
8032 SFR registers also occupy the same physical address range as IDATA, SFRs will not
be accessed by Register Indirect mode. SFRs may only be accesses using Direct address
mode. For example:
MOV A, @R0
; Move into the accumulator the
; contents of IDATA SRAM that is
; pointed to by the address
; contained in R0.
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