mtfsb1

Move To FPSCR Bit 1

mtfsb1 BT

Sets a specific bit in the FPSCR.

Encoding

Binary Layout

63

0:5

BT

6:10

/

11:15

/

16:20

38

21:30

/

31

 

Format X-form

Opcode 0xFC00004C

Extension Floating-Point

Operands

• BT
  Bit Index

Example

mtfsb1 0

Registers Altered

FPSCR

Related

More in Floating-Point

Reference

View in PowerISA v3.1C Specification ↗ OPF Power ISA v3.1C

Description

Sets (sets to 1) the FPSCR bit specified by BT. The FPSCR bits are numbered 0-31. Setting certain FPSCR bits (e.g., rounding mode or enable flags) can alter the behavior of subsequent floating-point operations.

Operation

FPSCR[BT] ← 1

Programming Note

This instruction is used to enable a specific floating-point exception. Ensure that the FPSCR register is properly managed to avoid unintended exceptions. This operation requires supervisor privilege level.