Hardware trigger generation from a declarative protocol description

Patent metadata

Field	Value
Publication number	US-2016119217-A1
Application number	US-201414574111-A
Country	US
Kind code	A1
Filing date	Dec 17, 2014
Priority date	Oct 24, 2014
Publication date	Apr 28, 2016
Grant date	—

Abstract

A test-and-measurement instrument is described. A state machine, corresponding to a regular expression, can be stored in the test-and-measurement instrument. The state machine can be modified to reflect a trigger condition received from a user. The modified state machine can then be used to invoke a trigger when the condition is met in the bits of a bit stream.

First claim

What is claimed is:

1 . A system, comprising:
a test-and-measurement instrument; a memory in the test-and-measurement instrument, the memory storing a state machine, the state machine corresponding to a regular expression; a receiver to receive from a user a trigger condition; and a state machine modifier to modify the state machine to reflect the trigger condition.

2 . A system according to claim 1 , wherein the trigger condition includes a compound trigger condition.

3 . A system according to claim 2 , wherein the state machine modifier is operative to replicate the state machine for each value in the compound trigger condition, modify each replicated state machine to incorporate one value of the compound trigger condition, and combine the modified replicated state machines.

4 . A system according to claim 1 wherein:
the receiver is operative to receive a bit stream;
the system further comprises:
a processing engine to process the bit stream using the state machine; and
a trigger system to send a trigger if the trigger condition is met.

5 . A system according to claim 1 , wherein the state machine modifier includes a state machine optimizer.

6 . A system according to claim 5 , wherein the state machine optimizer is operative to remove any states that occur after the trigger condition is met from the modified state machine.

7 . A system according to claim 5 , wherein the state machine optimizer is operative to combine states that can be satisfied in the trigger condition by any value into a single state.

8 . A system according to claim 1 , wherein the state machine modifier is operative to set the state machine to compare the bit stream with a user-selected value.

9 . A system according to claim 1 , wherein:
the receiver is operative to receive the regular expression from the user; and the system further comprises a state machine generator to generate the state machine from the regular expression.

10 . A system according to claim 9 , further comprising a state machine optimizer to optimize the state machine.

11 . A method, comprising:
identifying a state machine stored in a test-and-measurement instrument, the state machine corresponding to a regular expression; receiving from a user a trigger condition; identifying a state in the state machine used in the trigger condition received from the user; modifying the identified state in the state machine to reflect the trigger condition received from the user; and storing the modified state machine in the test-and-measurement instrument.

12 . A method according to claim 11 , wherein:
receiving from a user a trigger condition includes receiving from the user a compound trigger condition; identifying a state in the state machine used in the trigger condition received from the user includes identifying a plurality of states in the state machine used in the compound trigger condition received from the user; and modifying the identified state in the state machine to reflect the trigger condition received from the user includes:
replicating the state machine for each value in the compound trigger condition;
modifying an identified state in the replicated state machine to reflect a corresponding value in the trigger condition received from the user; and
combining the replicated state machines.

13 . A method according to claim 11 , further comprising:
receiving a bit stream; processing the bit stream using the modified state machine; and if the state machine indicates that the trigger condition is met, applying a triggering system of the test-and-measurement instrument.

14 . A method according to claim 11 , wherein modifying the identified state in the state machine to reflect the trigger condition received from the user includes optimizing the modified state machine.

15 . A method according to claim 14 , wherein optimizing the modified state machine includes removing any states that occur after the trigger condition is met from the modified state machine.

16 . A method according to claim 14 , wherein optimizing the modified state machine includes merging adjacent states that can be satisfied in the trigger condition by any value into a single state.

17 . A method according to claim 11 , wherein modifying the identified state in the state machine to reflect the trigger condition received from the user includes modifying the identified state to compare the bit stream with a user-selected value.

18 . A method according to claim 11 , wherein identifying a state machine stored in a test-and-measurement instrument includes:
receiving the regular expression from the user; and generating the state machine from the regular expression.

19 . A method according to claim 18 , wherein identifying a state machine stored in a test-and-measurement instrument further comprises optimizing the state machine.

Assignees

• Tektronix Inc

Inventors

• Tanous Edward F
• Rule Keith D
• Feist James

Classifications

• H04L43/10

  Active monitoring, e.g. heartbeat, ping or trace-route · CPC title

• H04L43/18 Primary

  Protocol analysers · CPC title

• G01R31/31903 Primary

  tester configuration · CPC title

• G11C29/56

  External testing equipment for static stores, e.g. automatic test equipment [ATE]; Interfaces therefor · CPC title