Motorola DSP96002 User Manual page 512

32-bit digital signal processor
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If there are wait states, (i.e., assumption 4 is not applicable) then to each 1-word instruction timing a "+ap"
term should be added and to each 2-word instruction a "+(2 * ap)" term should be added to account for the
program memory wait states spent to fetch an instruction word to fill the pipeline.
A.9.10 Jump Instructions Timing Summary
Figure A-17 Jump Instruction Timing Summary
The "ea" term in the Jbit equations refers only to the clock cycles spent in X and Y Data memory accesses
to obtain the bit to be tested. The "ea" term in the Jxxx equation refers only to the clock cycles spent while
calculating the jump target address.
All one-word jump instructions execute TWO program memory fetches to refill the pipeline and this is rep-
resented by the "+(2 * ap)" term.
All two-word jumps execute THREE program memory fetches to refill the pipeline but one of those fetches
is sequential (the instruction word located at the jump instruction 2nd word address+1),and so it is not
counted as per assumption 4. If the jump instruction was fetched from a program memory segment with
wait states, another "ap" should be added to account for that third fetch.
A.9.11 RTI/RTR/RTS Timing Summary
A - 324
Jump Instruction Operation
Jbit I/O Short
Jbit Absolute Short
Jbit Register Direct
Jbit X Memory
Jbit Y Memory
Jxxx
where Jbit = JCLR, JSCLR, JSET, JSSET, BRCLR, BSCLR,
BRSET and BSSET
Jxxx = Jcc, JMP, JScc, JSR, Bcc, BRA, BScc and BSR
Operation
RTI
RTR
RTS
Figure A-18 RTI/RTR/RTS Timing Summary
DSP96002 USER'S MANUAL
+ jx
Cycles
aio + (2 * ap)
2 * ap
2 * ap
ea + ax + (2 * ap)
ea + ay + (2 * ap)
ea + (2 * ap)
+ rx cycles
2 * ap
2 * ap
2 * ap
MOTOROLA

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