Status sensing and transmitting circuit

Claim 2

A status sensing apparatus for monitoring and indicating the status and location of a load means, and for transmission with a communication network producing message frames comprising a load signal means for producing a load signal, load address means for identifying said load signal, a storage means having an input means connected to the load signal means and having an output means, a comparator means coupled to the input means and the output means of the storage means and operable to generate an interrupt signal in response to a selected difference of the input means and the output means, and transfer means coupled to said comparator means and operable to enable said load address means and said load signal means to transmit to the communication network to request a mEssage frame and to introduce said load signal to a message frame.

Claim 3

The status sensing apparatus of claim 1 wherein said storage means includes clock means for resetting the output means to correspond to the input means, said transfer means including storage means connected to said comparator means to establish a latched request signal for communication with said network and having a reset means, and coded connection means connected to said clock means and to the reset means and responsive to a coded command message frame.

Claim 4

The status sensing apparatus of claim 1 for monitoring and indicating the status of a plurality of contact means, the status of each contact means being recorded in adjacent single bit binary signals in a multiple bit message frame, said storage means having an input means and a corresponding output means for each contact means, said comparator means including a plurality of comparator elements coupled to the corresponding input means and output means for each of the contact means, a combining logic means connected to each of said comparator elements and to said transfer means, said transfer means including means to obtain a message frame of the network and operable to insert the address means and the status of said plurality of contact means in said message frame.

Claim 5

The status sensing apparatus of claim 3 wherein said transfer means includes a gated flip-flop unit connected to the combining logic means and having a clock input, a pulse circuit connected to said combining logic means and operable to generate a delayed pulse, said pulse circuit being connected to said clock input to delay setting of said flip-flop unit.

Claim 6

The status sensing apparatus of claim 1 having a loop communication connecting means including a binary coded coupling circuit responsive to a multiple message frame, and having address decoding and encoding means, and said transfer means including first means operable to insert the address and the load signal into a message frame, and reset means connected to respond to a subsequently received coded message frame to update the storage means and resetting the comparator means to remove the interrupt signal.

Claim 7

The status sensing apparatus of claim 5 wherein said reset means further introduces the status into the coded message frame.

Claim 8

In combination, a contact status sensing load module for a data loop communication system having a plurality of remote stations including at least one load module and a loop controller generating and transmitting to said stations in timed relation a plurality of multiple bit message frames each including a module address byte and a data byte and a command byte, each of said remote stations including a frame logic circuit for receiving each of said message frames and selectively transmitting a frame via a common module bus to the load modules, at least one of said load modules being a status sensing load module having monitored contacts comprising a module address decoding means, a module address encoding means, a contact isolating network coupled to said monitored contacts and establishing a related electrically isolated logic signal identifying the contact status, a storage register having an input means connected to the isolating network to receive said logic signal and having an internal storage means for each input means to receive said signal in response to a clock command signal at a clock input, said register having an output means for each of said input means, a logic comparator having a first input connected to the input means and a second input connected to the output means of the register to generate a frame request interrupt signal in response to the relative condition of the logic signals to said comparator, and data logic means connecting said isolating network to said bus and having an enable input connected to said decoding means for selective transfer of the contact status to the network.

Claim 9

In combination, a contact status sensing load module for a data loop communication system having a plurality of remote stations including at least one load module and a loop controller generating and transmitting to said stations in timed relation a plurality of multiple bit message frames each including a module address byte and a data byte and a command byte, each of said remote stations including a frame logic circuit for receiving each of said message frames and selectively transmitting a frame via a common module bus to the load modules, at least one of said load modules being a status sensing load module having monitored contacts comprising a module address decoding means, a module address encoding means, a contact isolating network coupled to said monitored contacts and establishing a related electrically isolated logic signal identifying the contact status, a storage register having an input means connected to the isolating network to receive said logic signal and having an internal storage means for each input means to receive said signal in response to a clock command signal at a clock input, said register having an output means for each of said input means, a logic comparator having a first input connected to the input means and a second input connected to the output means of the register to generate a frame request interrupt signal in response to the relative condition of the logic signals to said comparator, and data logic means connecting said isolating network to said bus and having an enable input connected to said decoding means for selective transfer of the contact status to the network.

Claim 10

The combination of claim 7 wherein the load module inCludes a set-reset circuit including priority logic means and being connected to the comparator and set in response to an interrupt request signal, priority input signal and an interrupt strobe and enable signal and having an output connected to said bus to transmit the signal to the frame logic circuit.

Claim 11

The combination of claim 8 wherein the set-reset circuit includes a flip-flop register circuit having a set input connected to said comparator and a clock input and having a frame request line connected to said priority logic means, and a pulse circuit having an input connected to said comparator to generate a delayed pulse signal and being connected to said clock input.

Claim 12

The combination of claim 7 wherein the isolating network of the status sensing load module includes a sensing coil connected in series with a contact connecting means for connection to the monitored contacts and having a set of isolated sensing contacts coupled to said coil, a logic power supply means having a common logic ground, a resistor connected in series with the power supply means and said sensing contacts, with the sensing contacts connected between the resistor and the common logic ground to define a sensing point connected to the input means of the storage register.

Claim 13

The combination of claim 7 wherein the comparator of the load module includes a plurality of dual input logic gate means having a first input connected to each register input means and a second input connected to each related output means of the register to generate said frame request interrupt signal, a combining gate means having individual inputs connected to each of the comparator logic gate means and establishing said interrupt input signal in response to a signal from any of said logic gate means, a flip-flop circuit having a set input connected to said combining gate means and a clock input and having a frame request line connected to said common bus, and a pulse circuit having an input connected to the combining gate means having an output connected to said clock input, said pulse circuit establishing a delayed pulse to enable said flip-flop circuit a predetermined time after establishment of an interrupt request signal.

Claim 14

The combination of claim 11 wherein the interrupt signal is connected to the loop system to select a circulating loop message frame and said data logic means is operable to insert the address of the module and the status of the contact means in each selected frame, said module responding to a dedicated message frame including its address and a command signal to reset said flip-flop circuit, up-date said storage register and again insert the contact status into said dedicated message frame.

Claim 15

The combination of claim 7 wherein said data logic means includes a common output means connected to said bus and a first input means connecting said contact isolating network to said common output means and a second input means connecting the address encoding means to said common output means, and strobe signal means for selectively activating said first and second input means.

Claim 16

The combination of claim 13 wherein said common output means includes an enable input, and means responsive to a frame command signal and responsive to an interrupt signal to transmit the contact status to the loop controller.

Claim 17

The combination of claim 7 wherein selected modules at a remote station having priority patterns for receiving available frames and each of the selected modules includes a priority logic circuit connected to each other and operable to disable all lower priority modules in response to creation of an interrupt request signal generated within the point module, said priority logic circuit including first logic means combining the request signal with priority signals of other modules to establish a pair of output signals including a priority output signal and a transfer signal, transferring logic means processing the transfer signal to generate the interrupT signal and an interrupt request-granted signal, and means connecting the granted signal to said data logic means.

Claim 18

A contact status sensing module for a data loop communication system having a loop controller generating in timed relation a plurality of multiple bit message frames for receiving binary information relating to a plurality of monitored contact means, comprising a contact sensing network including a sensing coil connected in series with a contact connecting means for connection to the monitored contact means and having a set of sensing contacts coupled to said coil, a logic power supply means having a common logic ground, and a resistor connected in series with the power supply means and said sensing contacts with connection of the contacts and resistor constituting a binary logic signal point for connection to said loop communication system.

Claim 19

A contact status sensing module for a data loop communication system having a loop controller generating in timed relation a plurality of multiple bit message frames for receiving binary information relating to a plurality of monitored contact means, comprising a contact sensing network including a sensing coil connected in series with a contact connecting means for connection to the monitored contact means and having a set of sensing contacts coupled to said coil, a logic power supply means having a common logic ground, and a resistor connected in series with the power supply means and said sensing contacts with connection of the contacts and resistor constituting a binary logic signal point for connection to said loop communication system.