dsp56800 Freescale Semiconductor, Inc, dsp56800 Datasheet - Page 251

• Manufacturer Part Number: dsp56800
• Description: 16-bit Digital Signal Controllers
• Manufacturer: Freescale Semiconductor, Inc

Freescale Semiconductor
The term “2 * ap” represents the two instruction fetches done by the
RTI/RTS instruction to refill the pipeline. The ax term represents fetching
the return address from the software stack when the stack pointer points to
external X memory, and the 2 * ax term includes both this fetch and the
fetch of the SR as performed by the RTI and RTS instructions.
Address Register Indirect
No update
Post-increment by 1
Post-decrement by 1
Post addition by offset N
Indexed by offset N
Special
Immediate data
Immediate short data
Absolute address
Absolute short address
I/O short address
Implicit
Indexed by short displacement
Indexed by long displacement
Effective Addressing Mode
Table A-19. Addressing Mode Timing Summary
Register
X memory
Table A-18. TSTW Timing Summary
Table A-17. RTS Timing Summary
TSTW Operation
RTI, RTS
Operation
Instruction Set Details
NOTE:
2 * ap + 2 * ax
+rx Cycles
0
0
0
0
0
1
0
1
0
0
0
0
1
0
ea + ax
+ ea Words
+mv Cycles
0
0
0
0
2
2
0
2
0
0
0
2
4
+ ea Cycles
A-21