Texas Instruments TMS320C28x User Manual

XRETC COND
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XRETC COND C2xLP Source-Compatible Conditional Return
SYNTAX OPTIONS OPCODE OBJMODE RPT CYC
XRETC COND 0101 0110 1111 COND 1 − 4/7
Operands COND Conditional codes:
COND Syntax Description Flags Tested
0000 NEQ Not Equal To Z = 0
0001 EQ Equal To Z = 1
0010 GT Greater Then Z = 0 AND N = 0
0011 GEQ Greater Then Or Equal To N = 0
0100 LT Less Then N = 1
0101 LEQ Less Then Or Equal To Z = 1 OR N = 1
0110 HI Higher C = 1 AND Z = 0
0111 HIS, C Higher Or Same, Carry Set C = 1
1000 LO, NC Lower, Carry Clear C = 0
1001 LOS Lower Or Same C = 0 OR Z = 1
1010 NOV No Overflow V = 0
1011 OV Overflow V = 1
1100 NTC Test Bit Not Set TC = 0
1101 TC Test Bit Set TC = 1
1110 NBIO BIO Input Equal To Zero BIO = 0
1111 UNC Unconditional −
Description Return conditionally. If the specified condition is true, a 16-bit value is
popped from the stack and stored into the low 16 bits of the PC while the
upper 6 bits of the PC are forced to 0x3F; Otherwise, execution continues
with the instruction following the XRETC operation:
if(COND = true)
{
SP = SP − 1;
PC = 0x3F:[SP];
}
else
PC = PC + 1;
Note: This instruction can only transfer program control to a location located in the upper 64K
range of program space (0x3F0000 to 0x3FFFFF). To return from a call made by
XCALL, the XRETC instruction must be used. The cycle times for this operation are:
If (COND = true) then the instruction takes 7 cycles.
If (COND = false) then the instruction takes 4 cycles.
Flags and
Modes
V
If the V flag is tested by the condition, then V is cleared.
Repeat This instruction is not repeatable. If this instruction follows the RPT
instruction, it resets the repeat counter (RPTC) and executes only once.

Texas Instruments TMS320C28x Specifications

General

Brand	Texas Instruments
Model	TMS320C28x
Category	Processor
Language	English