Datasheet

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ST7LITE20F2 ST7LITE25F2 ST7LITE29F2 Instruction set
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The indexed addressing mode consists of three submodes:
• Indexed (no offset)
There is no offset, (no extra byte after the opcode), and it allows 00 - FF addressing
space.
• Indexed (short)
The offset is a byte, thus requiring only one byte after the opcode and allows
00 - 1FE addressing space.
• Indexed (long)
The offset is a word, thus allowing 64 Kbyte addressing space and requires 2 bytes
after the opcode.
12.1.5 Indirect (short, long)
The required data byte to do the operation is found by its memory address, located in
memory (pointer).
The pointer address follows the opcode. The indirect addressing mode consists of two
submodes:
• Indirect (short)
The pointer address is a byte, the pointer size is a byte, thus allowing 00 - FF
addressing space, and requires 1 byte after the opcode.
• Indirect (long)
The pointer address is a byte, the pointer size is a word, thus allowing 64 Kbyte
addressing space, and requires 1 byte after the opcode.
12.1.6 Indirect indexed (short, long)
This is a combination of indirect and short indexed addressing modes. The operand is
referenced by its memory address, which is defined by the unsigned addition of an index
register value (X or Y) with a pointer value located in memory. The pointer address follows
the opcode.
The indirect indexed addressing mode consists of two submodes:
• Indirect indexed (short)
The pointer address is a byte, the pointer size is a byte, thus allowing 00 - 1FE
addressing space, and requires 1 byte after the opcode.
• Indirect indexed (long)
The pointer address is a byte, the pointer size is a word, thus allowing 64 Kbyte
addressing space, and requires 1 byte after the opcode.
I
Table 52. Long and short instructions supporting direct, indexed,
indirect and indirect indexed addressing modes
Long and short instructions Function
LD Load
CP Compare
AND, OR, XOR Logical operations
ADC, ADD, SUB, SBC Arithmetic Additions/Subtractions operations
BCP Bit Compare