Method and apparatus for analyzing integrated circuit operations
A method and apparatus for viewing and/or analyzing the operations and logical states of an integrated circuit. The logical state of various flip-flops within the ASIC may be determined at a specified time. The embodiment may store these flip-flop states in a computer-readable data structure, such as a file or database. By repeating this process and incrementing or decrementing the time with each repetition, a more complete picture of the ASIC's operation may be captured. Additionally, the embodiment may graphically display the flip-flop states, for example as a graph or waveform.
1. A method for outputting the operations of an integrated circuit, comprising the operations of:
reaching a trigger event occurring at a trigger time;
waiting a number of clock cycles after the occurrence of the trigger event;
reading a state of a last flip-flop of a set of flip-flops in a chain; and
determining if an additional read of the state of the last flip-flop is to be performed;
in response to determining no additional read of the state of the last-flip flop is to be performed, storing as data every state of the last flip-flop since a first read of the state of the last flip-flop;
linking each state of the last flip-flop stored as data to a unique one of the set of flip-flops in the chain; and
wherein the data is stored by a computer system in a waveform database that is computer-readable.
2. The method of claim 1 , further comprising the operation of storing the state of the last flip-flop in a computer-readable medium.
3. The method of claim 1 , further comprising the operation of freezing the state of all of the set of flip-flops after the operation of waiting a number of clock cycles after the occurrence of the trigger event.
4. The method of claim 3 , further comprising the operation of incrementing a state from a next-to-last flip-flop in the chain to the last flip-flop in the chain.
5. The method of claim 4 , wherein the operation of incrementing a state comprises:
discarding the state of the last flip-flop; and
passing the state of the next-to-last flip-flop to the last flip-flop.
6. The method of claim 5 , further comprising the operation of:
in response to determining an additional read of the state of the last flip-flop is to be performed, performing operations a), b), c), and d) again.
7. The method of claim 6 , further comprising the operation of:
using the waveform database that is computer-readable to generate a graphical output, the graphical output displaying a graph of the state of all flip-flops in the chain at a time equal to the trigger time plus the number of clock cycles.
8. The method of claim 1 , further comprising:
determining whether an additional viewing of the operations of the integrated circuit is to be performed;
in the event an additional viewing of the operations of the integrated circuit is to be performed, incrementing the number of clock cycles by one; and
performing operations a), b), c), and d) again.
9. The method of claim 8 , wherein the operation of incrementing a state comprises:
discarding the state of the last flip-flop; and
passing the state of the next-to-last flip-flop to the last flip-flop.
10. The method of claim 9 , further comprising the operation of:
in response to determining an additional read of the state of the last flip-flop is to be performed, performing operations a), b), c), and d) a second time.
11. A computer-readable medium containing instructions which, when executed, perform the method of claim 10 .
12. An apparatus configured to perform the method of claim 10 .
13. The method of claim 10 , further comprising the operations of:
in response to determining no additional read of the state of the last-flip flop is to be performed, storing as data every state of the last flip-flop since a first read of the state of the last flip-flop; and
linking each state of the last flip-flop stored as first data to a unique one of the set of flip-flops in the chain.
14. The method of claim 13 , further comprising the operations of:
in response to incrementing the number of cycles and determining for a second time no additional read of the state of the last-flip flop is to be performed, storing as second data every state of the last flip-flop since a first read of the state of the last flip-flop and prior to incrementing the number of cycles; and
linking each state of the last flip-flop stored as second data to a unique one of the set of flip-flops in the chain.
15. The method of claim 14 , further comprising the operation of creating a graphical display from the first and second data.
16. The method of claim 15 , wherein the graphical display comprises:
a first frame corresponding to the first data; and
a second frame corresponding to the second data.
17. The method of claim 16 , wherein the graphical display is non-static.
18. The method of claim 1 , further comprising performing operations a) and b) during operation of the integrated circuit.
19. The method of claim 1 , further comprising performing operations a), b), c), and d) in an operating environment of the integrated circuit.
20. The method of claim 1 , wherein the integrated circuit is an application-specific integrated circuit.
21. The method of claim 20 , wherein:
the integrated circuit comprises a logic block; and
operations a), b), c), and d) are executed on the logic block.
22. A method for outputting the operations of an integrated circuit, comprising the operations of:
reaching a trigger event occurring at a trigger time;
waiting a number of clock cycles after the occurrence of the trigger event;
freezing a state of each of a set of flip-flops;
reading the state of a last flip-flop of the set of flip-flops;
determining an additional read of the state of the last flip-flop is to be performed;
in response to determining no additional read of the state of the last-flip flop is to be performed, storing as data every state of the last flip-flop since a first read of the state of the last flip-flop;
linking each state of the last flip-flop stored as data to a unique one of the set of flip-flops in the chain; and
wherein the data is stored by a computer system in a waveform database that is computer-readable.