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Semiconductor Group
180
Instruction Set
MOVC
A, @A + <base-reg>
Function:
Move code byte
Description:
The MOVC instructions load the accumulator with a code byte, or constant from
program memory. The address of the byte fetched is the sum of the original
unsigned eight-bit accumulator contents and the contents of a sixteen-bit base
register, which may be either the data pointer or the PC. In the latter case, the PC
is incremented to the address of the following instruction before being added to the
accumulator; otherwise the base register is not altered. Sixteen-bit addition is
performed so a carry-out from the low-order eight bits may propagate through
higher-order bits. No flags are affected.
Example:
A value between 0 and 3 is in the accumulator. The following instructions will
translate the value in the accumulator to one of four values defined by the DB
(define byte) directive.
REL_PC: INC
A
MOVC
A, @A + PC
RET
DB
66H
DB
77H
DB
88H
DB
99H
If the subroutine is called with the accumulator equal to 01H, it will return with 77H
in the accumulator. The INC A before the MOVC instruction is needed to ”get
around” the RET instruction above the table. If several bytes of code separated the
MOVC from the table, the corresponding number would be added to the
accumulator instead.
MOVC
A, @A + DPTR
Operation:
MOVC
(A)
←
((A) + (DPTR))
Bytes:
1
Cycles:
2
Encoding:
1 0 0 1
0 0 1 1
*
Summary of Contents for SAB 80515 Series
Page 9: ...Semiconductor Group 9 Introduction Figure 1 2 Block Diagram ...
Page 12: ...Semiconductor Group 12 Fundamental Structure Figure 2 1 Detailed Block Diagram ...
Page 18: ...Semiconductor Group 18 Central Processing Unit Figure 3 1 Fetch Execute Sequence ...
Page 73: ...Semiconductor Group 73 On Chip Peripheral Components Figure 7 25 A D Converter Block Diagram ...
Page 83: ...Semiconductor Group 83 On Chip Peripheral Components Figure 7 33 a Timer 2 Block Diagram ...
Page 215: ...Device Specifications Semiconductor Group 215 ...
Page 217: ...Device Specifications Semiconductor Group 217 Pin Configuration P LCC 68 ...
Page 219: ...Device Specifications Semiconductor Group 219 Logic Symbol ...
Page 226: ...Device Specifications Semiconductor Group 226 Figure 1 Block Diagram ...
Page 229: ...Device Specifications Semiconductor Group 229 Figure 2 Memory Address Spaces ...
Page 239: ...Device Specifications Semiconductor Group 239 Figure 4 Block Diagram of the A D Converter ...
Page 241: ...Device Specifications Semiconductor Group 241 Figure 5 Interrupt Request Sources ...
Page 242: ...Device Specifications Semiconductor Group 242 Figure 6 Interrupt Priority Level Structure ...