DP805x Instructions set details
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3.26. MOVX
Instruction:
Function:
MOVX <dest-byte>, <src-byte>
Move external
Description: The MOVX instructions transfer data between the accumulator and a
byte of external data memory, hence the X appended to MOV. There
are two types of instructions, differing in whether they provide an eight-
bit or sixteen-bit indirect address to the external data RAM.
In the first type, the contents of R0 or R1 in the current register bank
provides an eight-bit address, in the second type of MOVX instructions,
the data pointer generates a sixteen-bit address.
3.26.1.
MOVX A, @RI
Operation: (PC) ← (PC) + 1
(A) ← ((Ri))
Bytes:
1
Cycles:
3*
Encoding:
1
1
1
0
0
0
1
i
3.26.2.
MOVX A, @DPTR
Operation: (PC) ← (PC) + 1
(A) ← ((DPTR))
Bytes:
1
Cycles:
2*
Encoding:
1
1
1
0
0
0
0
0
* MOVX cycles depends on STRETCH register. Shown values with STRETCH=0.
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