1 / 16

Fetch Execute Cycle – loop

Fetch Execute Cycle – loop. Fetch Execute Cycle . Start PC = 20 MOVLW to I.R. MOVLW to Decode and Control. 2 0. MOVLW. MOVLW. Fetch Execute Cycle . 2 PC = PC + 1 = 21 O3 to I.R. 03 to W register. 21. 03. MOVLW. 03. Fetch Execute Cycle . 3 PC = PC + 1 = 22 MOVWF to I.R.

edison
Download Presentation

Fetch Execute Cycle – loop

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Fetch Execute Cycle – loop

  2. Fetch Execute Cycle Start PC = 20 MOVLW to I.R. MOVLW to Decode and Control 20 MOVLW MOVLW

  3. Fetch Execute Cycle 2 PC = PC + 1 = 21 O3 to I.R. 03 to W register 21 03 MOVLW 03

  4. Fetch Execute Cycle 3 PC = PC + 1 = 22 MOVWF to I.R. MOVWF to Instruction Decode and Control 22 MOVWF MOVWF 03

  5. Fetch Execute Cycle 4 PC = PC + 1 = 23 70 to I.R. 70 to ADDR MUX 03 from W register to Address 70 23 70 70 03 MOVWF 03

  6. Fetch Execute Cycle 5 PC = PC + 1 = 24 DECFSZ to I.R. DECFSZ to Instruction Decode and Control 24 DECFSZ 03 DECFSZ 03

  7. Fetch Execute Cycle 6 PC = PC + 1 = 25 70 to I.R. 70 to ADDR MUX 1 subtracted from contents of 70 Check to see if answer is Zero – NOT ZERO 25 70 70 02 DECFSZ 03

  8. Fetch Execute Cycle 7 PC = 27 GOTO to I.R. GOTO to Instruction Decode and Control 27 70 GOTO 02 GOTO 03

  9. Fetch Execute Cycle 7 PC = PC +1 = 28 24 to I.R. 28 24 02 GOTO 03

  10. Fetch Execute Cycle 8 PC = 24 DECFSZ to I.R. DECFSZ to Instruction Decode and Control 24 DECFSZ 02 DECFSZ 03

  11. Fetch Execute Cycle 9 PC = PC + 1 = 25 70 to I.R. 70 to ADDR MUX 1 subtracted from contents of 70 Check to see if answer is Zero – NOT ZERO 25 70 70 01 DECFSZ 03

  12. Fetch Execute Cycle 10 PC = 27 GOTO to I.R. GOTO to Instruction Decode and Control 27 GOTO 01 GOTO 03

  13. Fetch Execute Cycle 11 PC = PC +1 = 28 24 to I.R. 28 24 01 GOTO 03

  14. Fetch Execute Cycle 12 PC = 24 DECFSZ to I.R. DECFSZ to Instruction Decode and Control 24 DECFSZ 01 DECFSZ 03

  15. Fetch Execute Cycle 13 PC = PC + 1 = 25 70 to I.R. 70 to ADDR MUX 1 subtracted from contents of 70 Check to see if answer is Zero – Answer ZERO 25 70 70 00 DECFSZ 03

  16. Fetch Execute Cycle 14 PC = PC + 1 = 26 SLEEP to I.R. SLEEP to Instruction Decode and Control Program halts 26 SLEEP 00 SLEEP 03

More Related