Computer trend recorder

Claim 2

The combination of: a stored program type process digital computer having: input means for receiving a plurality of primary element input signals to be stored and processed under control of said stored program, a priority interrupt logic circuit, a digital-to-analog converter at the output of said computer for outputting values to be utilized by an external device, a programmed interrupt server for interrupting the normal order of said program in response to said logic circuit, and memory means containing values to be accessed by said interrupt server, a multipoint analog recorder multiplexed to utilize a plurality of values from said computer, said recorder having: means for producing a priority interrupt signal, means for producing a reference signal in timed relation to the recording of at least one specific point, said reference signal synchronizing the output of said digital-to-analog converter with the point to be recorded on said multipoint analog recorder said logic circuit being responsive to said priority interrupt signal to output the next value to be utilized by said recorder.

Claim 3

The combination of: a stored program type process digital computer having: input means for receiving a plurality of primary element input signals to be stored and processed under control of said stored program, a digital to analog converter at the output of said computer, a programmed interrupt sever for interrupting the normal order of said program, a multipoint recorder, means for producing a next point signal in timed relation to the recording of each point on said multipoint analog recorder, interrupt apparatus comprising: means for producing an interrupt signal in response to said next point signal, said interrupt signal being applied to said computer to request said interrupt server to output the next point to be recorded, and means for producing a reference signal in timed relation to the recording of at least one specific point, said reference signal synchronizing the output of said digital to analog converter with the point to be recorded on said multipoint analog recorder.

Claim 4

The combination of: a stored program type process digital computer having: input means for receiving a plurality of primary element input signals to be stored and processed under control of said stored program, a digital to analog converter at the output of said computer, a programmed interrupt sever for interrupting the normal order of said program, a multipoint recorder, means for producing a next point signal in timed relation to the recording of each point on said multipoint analog recorder, interrupt apparatus comprising: means for producing an interrupt signal in response to said next point signal, said interrupt signal being applied to said computer to request said interrupt server to output the next point to be recorded, and means for producing a reference signal in timed relation to the recording of at least one specific point, said reference signal synchronizing the output of said digital to analog converter with the point to be recorded on said multipoint analog recorder.

Claim 5

The combination of: a stored program type process digital computer having: input means for receiving a plurality of primary element input signals to be stored and processed under control of said stored program, a digital-to-analog converter at the output of said computer, a programmed interrupt server for interrupting the normal order of said program, a memory containing a table of digital values representing the durations for effecting a timed sequence of events, a multipoint recorder, means for producing a next point signal in timed relation to the recording of each point on said multipoint recorder, said next point signal synchronizing the output of said digital-to-analog converter with the point to be recorded on said multipoint recorder, means for producing an interrupt signal in response to said next point signal, said interrupt signal being applied to said computer to request said interrupt server to output the next point to be recorded, a counter for receiving a digital output word related to one of said digital values, said counter being activated by said digital output word for updating elapsed time between events in accordance with said computed durations, and means for generating a count with said counter at a preset counting rate to produce a priority interrupt signal representing counter equals zero, said priority interrupt signal being applied to said computer to terminate the event currently timed out, said interrupt signal being applied to said computer to advance to the next of said digital values in said table and to update the elapsed time to equal the duration of said next event to be timed out.

Claim 6

The combination of: a stored program type process digital computer having: input means for receiving a plurality of primary element input signals to be stored and processed under control of said stored program, a digital-to-analog converter at the output of said computer, a programmed interrupt server for interrupting the normal order of said program, a memory containing a table of digital values representing the durations for effecting a timed sequence of events, a multipoint recorder, means for producing a next point signal in timed relation to the recording of each point on said multipoint recorder, said next point signal synchronizing the output of said digital-to-analog converter with the point to be recorded on said multipoint recorder, means for producing an interrupt signal in response to said next point signal, said interrupt signal being applied to said computer to request said interrupt server to output the next point to be recorded, a counter for receiving a digital output word related to one of said digital values, said counter being activated by said digital output word for updating elapsed time between events in accordance with said computed durations, and means for generating a count with said counter at a preset counting rate to produce a priority interrupt signal representing counter equals zero, said priority interrupt signal being applied to said computer to terminate the event currently timed out, said interrupt signal being applied to said computer to advance to the next of said digital values in said table and to update the elapsed time to equal the duration of said next event to be timed out.

Claim 7

The combination recited in claim 3 further including: a plurality of process control devices, each being actuated for time durations specified by said digiTal values representing computed durations, means for actuating said control devices at a common time, and means for terminating the actuation of each control device in response to said priority interrupt signal.