
JFD
SC140 DSP Core Reference Manual A-207
JFD Jump If False Using a Delay Slot (AGU) JFD
Description
If the T bit is cleared, program execution continues at a specified 32-bit memory destination address after
executing the execution set in the delay slot. If the T bit is set, the PC is updated to point to the next
execution set and program execution continues sequentially. The destination address cannot be in the
middle of an execution set.
Status and Conditions that Affect Instruction
Status and Conditions changed by Instruction
None.
Example
JFD R0
Operation Assembler Syntax
If T==0, then label → PC
JFD label [0 ≤ label < 2
32
,W]
If T==0, then Rn → PC JFD Rn
JFD label
Jumps to the absolute memory address specified by a label after executing the set in the delay slot. The
assembler and linker calculate the destination address from the label.
JFD Rn
Jumps to the memory address specified in an address register (Rn) after executing the execution set in the
delay slot.
Register Address Bit Name Description
SR[1] T True bit
Instruction Result
cmpeq.w #$35,d1 Not equal, so T bit in SR cleared.
move.w #adr,r0 Places the numerical address of adr in r0.
nop Delay needed after write to pointer.
jfd r0 move.w #$29,d1 Jump to adr, move.w executed.
inc d1 Increment d1 to $2A.
move.w #$47,d2 Skipped over.
- - - - Skipped over.
- - - - Skipped over.
- - - - Skipped over.
adr move.w #$1A,d4 Execution continues here at lbl.
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