Texas Instruments TMS320C28x Reference Manual page 278

LC *XAR7
SYNTAX OPTIONS
LC *XAR7
Operands *XAR7
Description
Flags and
Modes
Repeat
Example
; Call to subroutines in SwitchTable selected by Switch value:
SwitchTable:
.long
.long
MOVL
MOVZ
MOVL
LC
Switch0:
LRET
Switch1:
LRET
indirect program-memory addressing using auxiliary register XAR7, can ac-
cess full 4Mx16 program space range (0x000000 to 0x3FFFFF)
Indirect long call. The return PC value is pushed onto the software stack,
pointed to by SP register, in two 16-bit operations. Next, the destination
address stored in the XAR7 register is loaded into the PC:
temp(21:0) = PC + 1;
[SP] = temp(15:0);
SP = SP + 1;
[SP] = temp(21:16);
SP = SP + 1;
PC = XAR7(21:0);
Note: For more efficient function calls when operating with OBJMODE = 1, use the LCR and
LRETR instructions instead of the LC and LRET instructions.
None
This instruction is not repeatable. If this instruction follows the RPT
instruction, it resets the repeat counter (RPTC) and executes only once.
Switch0
Switch1
.
.
XAR2,#SwitchTable
AR0,@Switch
XAR7,*+XAR2[AR0]
*XAR7
.
.
.
.
.
.
OPCODE
0111 0110 0000 0100
; Switch address table:
; Switch0 address
; Switch1 address
; XAR2 = pointer to SwitchTable
; AR0 = Switch index
; XAR7 = SwitchTable[Switch]
; Indirect call using XAR7
; Subroutine 0:
; Return
; Subroutine 1:
; Return
LC *XAR7
Long Indirect Call
OBJMODE RPT CYC
X − 4
6-121