Freescale Semiconductor StarCore SC140 - Manual (Page 389)

BMCLR;Instruction Set:BMCLR
SC140 DSP Core Reference Manual A-75
BMCLR
Bit-Masked Clear a 16-Bit Operand (BMU)
BMCLR
Description
These operations use an unsigned 16-bit immediate data mask to clear selected bits in the destination
operand. For each bit i that is set (selected) in the mask, the bit i in the corresponding destination operand’s
bit position is cleared. Bits that are not selected as well as bits in the other part of the register are
unaffected. These operations read from a register, modify the retrieved value, and write the new value back
to that register.
Note: Special care must be taken when using this instruction to clear bits on the EMR register due to this
register’s special functionality. See Chapter 3 for a description of this behavior.
Status and Conditions that Affect Instruction
Operation Assembler Syntax
0
→ C1.H
i
(i denotes bits=1 in #u16) BMCLR #u16,C1.H {0
≤ u16 < 2 16
}
0
→ C1.L
i
BMCLR #u16,C1.L {0
≤ u16 < 2 16
}
0
→ DR.H
i
BMCLR #u16,DR.H {0
≤ u16 < 2 16
}
0
→ DR.L
i
BMCLR #u16,DR.L {0
≤ u16 < 2 16
}
BMCLR #u16,C1.H
Clears selected bits in the HP contents of a control register (C1).
BMCLR #u16,C1.L
Clears selected bits in the LP contents of a control register (C1).
BMCLR #u16,DR.H
Clears selected bits in the HP contents of a data or address register (DR).
BMCLR #u16,DR.L
Clears selected bits in the LP contents of a data or address register (DR).
Register Address Bit Name Description
SR[18] EXP Determines execution working mode for instructions that have these
registers as an operand.