SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
Store Halfword to Memory with a 3-Bit Unsigned Constant Offset
STH dst, *+baseR[ucst3]
Functional unit = D
16 bit
15 | 13 | 12 | 10 | 9 | 7 | 6 | 0 |
dst | baseR | ucst3 | 1 | 1 | 1 | 0 | 0 | 0 | 0 |
3 | 3 | 3 | opcode |
The 16 LSBs (halfword) of dst are stored to memory (effective address). The memory address is formed from a base address register (baseR) and an offset (number of halfwords) that is a 3-bit unsigned constant (ucst3). If an offset is not given, the assembler assigns an offset of zero. Brackets, [ ], must surround the specified offset, if using the optional offset parameter.
The square brackets, [ ], indicate that the ucst3 is scaled by a left-shift of 1 bit. After scaling, ucst3 is added to baseR. The result of the calculation is the effective address in memory that contains the content from dst.
Halfword addresses must be aligned on halfword (LSB is 0) boundaries.
None
*(baseR[ucst3]) = *dst