TSC80251G2D_06 Datasheet, PDF (39/77 Pages) ATMEL Corporation – 8/16-bit Microcontroller with Serial Communication Interfaces

AT/TSC8x251G2D
Table 32. Summary of Call and Return Instructions
Absolute callACALL <src>(PC) ← (PC) +2; push (PC)_15:0;
(PC)_10:0 ← src opnd
Extended callECALL <src>(PC) ← (PC) + size (instr); push (PC)_23:0;
(PC)_23:0 ← src opnd
Long callLCALL <src>(PC) ← (PC) + size (instr); push (PC)_15:0;
(PC)_15:0 ← src opnd
Return from subroutineRETpop (PC)_15:0
Extended return from subroutineERETpop (PC)_23:0
Return from interruptRETIIF [INTR = 0] THEN pop (PC)_15:0
IF [INTR = 1] THEN pop (PC)_23:0; pop (PSW1)
Trap interruptTRAP(PC) ← (PC) + size (instr);
IF [INTR = 0] THEN push (PC)_15:0
IF [INTR = 1] THEN push (PSW1); push (PC)_23:0
<dest>,
Mnemonic <src>⁽¹⁾
Comments
Binary Mode
Bytes States
Source Mode
Bytes States
ACALL
addr11
Absolute subroutine call
2
9⁽²⁾⁽³⁾
2
9⁽²⁾⁽³⁾
ECALL
at DRk
addr24
Extended subroutine call (indirect)
Extended subroutine call
3
14⁽²⁾⁽³⁾
2
13⁽²⁾⁽³⁾
5
14⁽²⁾⁽³⁾
4
13⁽²⁾⁽³⁾
LCALL
at WRj
addr16
Long subroutine call (indirect)
Long subroutine call
3
10⁽²⁾⁽³⁾
2
9⁽²⁾⁽³⁾
3
9⁽²⁾⁽³⁾
3
9⁽²⁾⁽³⁾
RET
Return from subroutine
1
7⁽²⁾
1
7⁽²⁾
ERET
Extended subroutine return
3
9⁽²⁾
2
8⁽²⁾
RETI
Return from interrupt
1
7⁽²⁾⁽⁴⁾
1
7⁽²⁾⁽⁴⁾
TRAP
Jump to the trap interrupt vector
2
12⁽⁴⁾
1
11⁽⁴⁾
Notes:
1. A shaded cell denotes an instruction in the C51 Architecture.
2. In internal execution only, add 1 to the number of states if the destination/return
address is internal and odd.
3. Add 2 to the number of states if the destination address is external.
4. Add 5 to the number of states if INTR = 1.
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