Background

[0001] Imaging systems, such as printers, copiers, etc , may be used to form markings on a physical medium, such as text, images, etc. In some examples, imaging systems may form markings on the physical medium by performing a print job. A print job can include forming markings such as text and/or images by transferring a print substance (e.g., ink, toner, etc.) to the physical medium.

Brief Description of the Drawings

[0002] Figure 1 illustrates an imaging device consistent with the disclosure.

[0003] Figure 2 illustrates an example controller consistent with the disclosure.

[0004] Figure 3 illustrates an example imaging device including a fill port consistent with the disclosure.

[0005] Figure 4 illustrates an example imaging device including a fill port consistent with the disclosure.

[0006] Figure 5 illustrates an example imaging device including a fill port consistent with the disclosure.

[0007] Figure 6 illustrates an example of a defection circuit of an imaging device consistent with the disclosure.

[0008] Figure 7 illustrates an example of a defection circuit of an imaging device consistent with the disclosure.

[0009] Imaging devices may include a supply of a print substance located in a reservoir. The print substance can be deposited onto a physical medium. As used herein, the term“imaging device” refers to any hardware device with functionalities to physically produce representation(s) (e.g., text, images, models, etc.) on a medium in some examples, a“medium” may include paper, photopo!ymers, plastics, composite, metal, wood, or the like. [0010] The reservoir including the print substance may be inside of the imaging device and contain a supply of the print substance such that the imaging device may draw the print substance from the reservoir as the imaging device creates the images on the print medium. As used herein, the term“reservoir” refers to a container, a tank, and/or a similar vessel to store a supply of the print substance for use by the imaging device.

[0011] An imaging device may include more than one reservoir such that various types (e.g., various colors) of print substance may be contained within the imaging device. Each reservoir containing the print substance may be connected to a fill port such that a user may fill the reservoir as the supply of print substance is used by the imaging device. As used herein, the term“fill port”, refers to an aperture, an area, and/or other opening connected to a print substance reservoir that receives a print substance and transfers the received print substance to the print substance reservoir (e.g., to replenish the print substance supply) included in the imaging device.

[0012] Each fill port may be accessible from the exterior of the imaging device such that a user may access the fill port to fill and/or re-fill the reservoir with the appropriate print substance as the volume of the print substance in the reservoir decreases. In some imaging devices, each fill port may include a corresponding fill port cover. As used herein, the term“fill port cover”, refers to an object that may obstruct a fill port, an aperture, an area, and/or an opening such that the fill port is obstructed. The fill port cover can protect the contents of the reservoir from the external environment.

[0013] A fill port cover may be opened in order to transfer print substance to the print substance reservoir. In some examples, a fill port cover may be left open after filling and/or refilling the reservoir. The fill port covers may prevent a print substance from evaporating and/or becoming contaminated. For example, when a fill port cover is left in an open position, the print substance may be exposed to external elements which may have a detrimental effect on the print substance performance and/or the fill port assembly. For example, a liquid print substance (e.g., ink) may dry out, evaporate, and/or become contaminated by external debris (e.g., dust etc.) when the fill port is left in the open position.

[0014] Some imaging devices may not include reservoirs that indicate the type of print substance in the reservoir, or how much print substance is in the reservoir. Thus, when the user attempts to fill the reservoir with a supply of the print substance, the potential for error (e.g., overfilling, refill of the wrong type, etc.) may occur in other examples, some imaging devices may include multiple print substance reservoirs each having corresponding fill ports. An imaging device with multiple reservoirs may make the filling operation tedious and complex, particularly in environments where several imaging devices are operating.

[0015] Fill port sensors according to the disclosure can include a detection circuit to detect a status of each fill port included on the imaging device. As used herein, the term“detection circuit” refers to an electrical circuit which can be utilized to determine a state of a fill port. For example, a detection circuit can be utilized to determine whether fill ports are open or closed. As used herein, the term“fill port status” refers to a condition of the fill port in some examples, the condition of the fill port can include being covered by a fill port cover, connected to a colorant container, or open (e.g., neither covered by a fill port cover or connected to a colorant container). The detection circuit provides a scheme to unambiguously encode the fill port status of the fill ports included in an imaging device. The detection circuit may include a mechanical and/or electronic switch at each fill port, to detect when a fill port has been opened, closed, and or attached to a colorant container. The detection circuit may provide a signal to a controller of the imaging device, and the imaging device may provide instructions to a user via a user interface regarding the detected status. The instructions provided to the user can help the user to determine whether the reservoir is full of print substance, is low on print substance, and/or whether a supply of the print substance is connected to a correct fill port to deliver a correct type of print substance to a corresponding reservoir, among other types of instructions.

[0018] In some examples described herein, each fill port cover corresponding to each fill port may include a resistive element (e.g., a resistor) such that when the fill port cover is closed, the resistor of the fill port cover is connected to the detection circuit. In this example, a determination may be made by the controller as to the status of the fill port. In some examples, the detection circuit may include a current sensor to detect the status of the fill ports. As used herein, the term“current sensor refers to a device that detects electric current in a circuit.

[0017] In some examples, the detection circuit may include an Analog to Digital Converter (ADC) to detect the status of the fill ports. As used herein, the term “ADC” refers to a device to convert an analog signal to a digital signal. For example, each fill port cover may include a resistor with a unique resistance value in this way, the detection circuit may detect a value (e.g., a current of the detection circuit via the current sensor or a digital signal via the ADC). Based on unique resistance values, a status of each fill port included in the imaging device can be determined in some examples described herein, the detection circuit may determine if each fill port is open, closed by the fill port cover, or whether the fill port is connected to a colorant container during a fill operation.

[0018] Figure 1 illustrates an imaging device consistent with the disclosure.

As illustrated in Figure 1 , an imaging device 100 may include a controller 102, a plurality of fill ports 104-1 , ... , 104-N, a plurality of fill port covers 106-1 , ... , 106-N, a plurality of resistors 108-1 , ... , 108-N, and a detection circuit 110. As used herein, the plurality of fill ports 104-1 ,... , 104-N may be collectively referred to as the plurality of fill ports 104. Likewise, the plurality of fill port covers 106-1 , ... , 106-N, and the plurality of resistors 108-1 , ... , 108-N may be collectively referred to as plurality of fill ports 106 and the plurality of resistors 108 respectively. Although not shown in Figure 1 for clarity and so as not to obscure examples of the disclosure, the imaging device 100 may include a corresponding reservoir connected to each fill port of the plurality of fill ports 104. Each of the plurality of fill ports 104 may include a fill port cover of the plurality of fill port covers 106, and each of the plurality of fill port covers 106 may include a resistor of the plurality of resistors 108. The plurality of fill ports 104 may be used to fill and/or refill the reservoir with a print substance that can be utilized by the imaging device, as described above.

[0019] For example, the print substance can be utilized by imaging device 100 to produce text, images, models, on a physical medium. As the print substance is utilized, the amount of print substance included in the reservoirs can be depleted. A fill operation may be performed to fill and/or re-fill the amount of print substance in the reservoirs. During a fill operation (e.g., the activity of a user or machine filling the reservoir with a print substance), a user may open one of the plurality of fill port covers 106. When one of the plurality of fill port covers 106 is in the open position a resistor of the plurality of resistors 108 may be disconnected from the detection circuit 110 by altering the position of a switch. Likewise, when one of the plurality of fill port covers 106 is in the dosed position, a resistor of the plurality of resistors 108 may be connected to the detection circuit 110 by altering the position of the switch. In some examples, the position of a switch included in the detection circuit 110 may be altered based on the plurality of resistors 108 included in the plurality of fill port covers 106

[0020] As used herein, the term“switch” refers to an electrical component that can break an electrical circuit, such as interrupting a current in the electrical circuit and/or diverting the current from one component to another. For example, when fill port cover 106-1 is opened, the switch corresponding to the corresponding fill port 104-1 can be opened, and the resistor 108-1 corresponding to that particular fill port 104-1 can be disconnected from the detection circuit 110. As used herein, the term “open switch”, refers to an instance where the switch corresponding to a particular fill port 104-1 is open, which indicates that the resistor corresponding to the respective fill port cover 106-1 has been disconnected from the detection circuit 110. As used herein, the term“closed switch”, refers to an instance in which current may pass through the switch in some examples, the fill port 104-1 may be dosed (e.g , resulting in a closed switch). The fill port 104-1 may be closed as a result of a colorant container occupying the fill port 104-1 , or by a fill port cover 106-1 occupying the corresponding fill port 104-1.

[0021] As used herein, the term“resistor” and/or“resistive element” refers to an electrical component that may engender electrical resistance (e.g., to restrict or reduce current flow) as a circuit element. For example, in detection circuit 110 the plurality of resistors 108 may adjust a signal detected by the detection circuit 110 based on the status of a fill port (e.g., fill port 104-1) corresponding to one or more resistor(s) of the plurality of resistors 108. As used herein, the term“signal” refers to a time-varying quantity of voltage to convey information that may be transmitted from one element to another element and/or from one device to another device. For example, a signal may be transmitted between devices to send and receive information.

[0022] In some examples, a signal being transmitted in detection circuit 110 may be detected by the detection circuit. The detected signal may be a detected current, a change in voltage, a change in resistance, and/or a value from an ADC, as is further described herein. The detected signal may vary based on a combination of statuses of the plurality of fill ports 104. For example, the signal detected by controller 102 when fill port 104-1 is open and fill ports 104-2, 104-3, and 104-N are closed can be a different signal than the signal detected by controller 102 when fill ports 104-2 and 104-3 are open and fill ports 104-1 and 104-N are dosed. In other words, based on the combination of fill ports 104 that are open/closed, the signal detected by controller 102 can be different. All of the values corresponding to the detected signals based on all possible combinations of statuses of the plurality of fill ports may be stored in a predetermined table. Controller 102 can access the predetermined table in order to determine a status of all of the plurality of ports 104 based on a signal received from the detection circuit 110, where the signal can be a detected current, a change in voltage, a voltage ratio, a change in resistance, and/or a value from an ADC, as is further described herein.

[0023] The table storing values corresponding to the various combinations of fill port statuses can vary based on resistance values of the plurality of resistors 108 For example, in some instances, the plurality of resistors 108 can each have a same resistance value. However, in some instances, the plurality of resistors 108 can each have a different resistance value. A predetermined table storing values corresponding to the various combinations of fill port statuses for the instance in which each of the plurality of resistors 108 have the same resistance value can be different than a predetermined table storing values corresponding to the various combinations of fill port statuses for the instance in which each of the plurality of resistors 108 have a different resistance value.

[0024] As described above, when a particular fill port cover or combination of fill port covers are opened, such as for a fill operation, a switch or combination of switches included in the detection circuit 110 may correspondingly be opened. As a result of the switch(es) included in the detection circuit 110 being opened, various combinations of resistors corresponding to the fill port covers 106 may be disconnected from the detection circuit 110 The various resistors that are disconnected from the detection circuit 110 as a result of fill port covers being opened (and corresponding switches being opened), the signals detected by detection circuit 110 can change. In other words, a current, a voltage, a voltage ratio, a resistance, and/or a value from an ADC, measured by detection circuit 110, can be different based on each combination of fill port covers that are

opened/closed. As used herein, the term“measure” and/or“measurement” refers to an amount and/or a degree of a value (e.g , a current, a voltage, a voltage ratio, a resistance, and/or a value from an ADC) ascertained by the detection circuit 110. [0025] As illustrated in Figure 1 , imaging device 100 can include four fill ports 104-1 , 104-2, 104-3, 104-N. in the example illustrated in Figure 1 , a total of sixteen different combinations of fill port statuses are possible based on imaging device 100 including four fill ports in some examples, as described above each of the plurality of resistors 108 can have the same resistance value. Based on the sixteen different combinations of fill port statuses and the plurality of resistors 108 having the same resistance value, sixteen different signals can be measured by detection circuit 110, by closing various combinations of switches in the detection circuit 110 and making multiple measurements. Based on the signal measured by detection circuit 110, controller 102 can compare the signal to a table Including the sixteen different signals to determine which combination of fill ports are open.

[0026] The plurality of fill ports 104 and the corresponding fill port covers 106 including a plurality of resistors 108 with the same resistance value may provide a simpler construction of the imaging device 100. In some scenarios this may save time and money during manufacturing of an imaging device. In some examples, the switch may be closed by a colorant container (not expressly pictured) being connected to the fill port 104-1. As such, power may be applied to each fill port of the plurality of fill ports 104 one fill port at a time as to detect if the switch is closed by the colorant container, or by a corresponding fill port cover of the plurality of fill port covers 106.

[0027] As illustrated in Figure 1 , imaging device 100 can include four fill ports 104-1 , 104-2, 104-3, 104-N. As previously described above, a total of sixteen different combinations of fill port statuses are possible based on imaging device 100 including four fill ports in some examples, as described above each of the plurality of resistors 108 can have a different resistance value. Based on the sixteen different combinations of fill port statuses and the plurality of resistors 108 having different resistance values, sixteen different signals can be measured by detection circuit 110. Based on the signal measured by detection circuit 110, controller 102 can compare the signal to a table including the sixteen different signals to determine which combination of fill ports are open. For example, when each of the plurality of resistors 108 has a substantially unique resistance value, the detection circuit 110 may detect a status of each of the plurality of fill ports 104. When the plurality of resistors 108 each have a different resistance value, the resulting change in resistance detected by the detection circuit 110 may provide a degree of resolution such that a single value may indicate a particular combination of fill port statuses. As mentioned above, the single value may be derived from a current sensor and/or an ADC included in the detection circuit 110.

[0028] As described above, power may be applied to the detection circuit 110, and a sensor (e.g., a current sensor and/or an ADC) may detect a particular signal. The signal can include a current, a change in resistance, a change in voltage ratio, and/or a change in voltage. Controller 102 may determine a value of the signal based on the unique combination of resistors 108 being either connected or disconnected from the detection circuit.

[0029] The sensor (e.g., the current sensor or ADC) may transmit the detected signal value to the controller 102, and the controller 102 may compare the detected signal value to a predetermined table. The predetermined table can indicate the fill port status of each fill port. For example, where each resistor of the plurality of resistors has a different resistance value (e.g., 108-1= 400 Ohms, 108-2= 200 Ohms, etc.), detection circuit 110 can detect a value (e.g., a current, a change in resistance, a change in a voltage divider ratio, a change in voltage, an ADC value) that corresponds to the status of the plurality of fill ports 104. Using Table 1 (below), controller 102 can compare the detected value with the predetermined values included in predetermined Table 1 to determine the status of the plurality of fill ports

[0030] As used herein, the term“predetermined value” refers to a value that may be an actual measurement and/or be derived from a change in voltage, change in voltage ratio, an ADC value, a change in resistance, a current of the detection circuit 110, etc. in some examples, the predetermined value may be determined in response to a current sensor detecting a current of the detection circuit 110. In some examples, the predetermined value may be derived from a voltage divider ratio, where the voltage divider ratio may change based on the status of the plurality of fill ports 104. In some examples, the predetermined value may be derived from information from an ADC included in the detection circuit 110. in some examples, the predetermined value may be an arbitrary number assigned to a particular combination of fill port statuses and determined by the controller 102.

[0031] For example, the detection circuit 110 may determine a predetermined value of 40, and the controller may compare the predetermined value of 40 to the Table 1 above and determine the fill port status of each fill port of the plurality of fill ports 104. in this particular example, the fill port 104-1 is open, the fill port 104-2 is closed, the fill port 104-3 is open, and the fill port 104-N is closed in the preceding example, the detection circuit 110 may further determine if the particular ports 104-2, and 104-N are closed from by the corresponding fill port covers 108-1 and 106-N, or by a colorant container.

[0032] For example, the controller 102 may probe each of the fill ports 104-2, and 104-N to query a container acumen that may be attached to a colorant container. As used herein, the term“colorant container” refers to a vessel, bottle, bag, box, carton, or other suitable receptacle for the transfer and/or containment of a print substance. As used herein, the term“container acumen” refers to a device that may be attached to a colorant container and include a memory that may contain information related to the colorant container to which it is connected. For example, container acumen may be attached to a colorant container (e.g , a bottle) and include information related to the contents, manufacturing, etc. of the print substance and/or colorant container. [0033] While Figure 1 illustrates imaging device 100 as including four fill ports, examples of the disclosure are not so limited. For example, an imaging device may have more or less than four fill ports. Likewise, while the plurality of resistors 108 are described as having specific resistance values, the resistors may have different resistance values that are higher or lower than the resistance values described by example herein.

[0034] Fill port sensors according to the disclosure can detect a status of a plurality of fill ports 104. Detection circuit 110 included in an imaging device may protect the imaging device and the print substance contained therein by alerting a user to the status of the fill port as being open, closed, or connected to a colorant container. In this way, the integrity of the fill ports and the print substance may be monitored and maintained.

[0035] Figure 2 illustrates an example controller 202 consistent with the disclosure. As illustrated in Figure 2, the controller 202 may include a processing resource 212, and a memory resource 214. As used herein, the processing resource 212 may be a central processing unit (CPU), a semiconductor-based

microprocessor, and/or other hardware devices suitable for retrieval and execution of instructions stored in non-transitory computer readable medium (e.g., the memory resource 214). The processing resource 212 may fetch, decode, and execute instructions. As an alternative or in addition to retrieving and executing instructions, the processing resource 212 may include an electronic circuit that includes electronic components for performing the functionality of instructions. As used herein, the memory resource 214 may also be referred to a non-transitory computer readable medium 214, and may be a volatile memory (e.g., RAM, DRAM, SRAM, EPROM, EEPROM, etc.) and/or non-volatile memory (e.g., a HDD, a storage volume, data storage, etc.) Although the following descriptions refer to a single processor and a single memory, the descriptions may also apply to a system with multiple processors and multiple memories. In such examples, the instructions may be distributed (e.g., stored) across multiple memories and the instructions may be distributed (e.g., executed by) across multiple processors.

[0036] In some examples, the memory resource 214 may store instructions which may be executed by the processing resource 212 to cause the controller 202 to determine a current of a detection circuit via a current sensor included in the detection circuit (e.g., the detection circuit 110). For example, the current detected by the detection circuit may indicate a status of a fill port of the plurality of fill ports (e.g., plurality of fill ports 104), alternatively, or in addition, the current detected by the current sensor may indicate a status of all of the fill ports of the plurality of fill ports. For example, when a particular fill port cover (e.g., the fill port cover 106-1) is open, a switch associated with the corresponding fill port (e.g., the fill port 104-1) may be open. The switch being open can remove the corresponding resistor (e.g., the resistor 108-1) from the detection circuit and thereby change the current of the detection circuit detected by the current sensor in the previous example, the controller 202 may identify that the status of the particular fill port is open based on the switch being open and the controller 202 detecting a change in current. In another example, the controller 202 may identify based on the current of the detection circuit that the particular fill port has is closed.

[0037] For example, the memory resource 214 may store instructions which may be executed by the processing resource 212 to cause the controller 202 to detect when the particular fill port is closed. The particular fill port (e.g., fill port 104- 1) may be closed by the corresponding particular fill port cover (e.g., fill port cover 106-1) and the corresponding resistor (e.g., the resistor 108-1) may be effectively connected to the circuit, thus dosing the switch and changing the current detected by the current sensor. The current detected by the current sensor may correspond to a predetermined value included in Table 1 previously described in connection with Figure 1. Thus, the controller 202 may compare the current sensor value (e.g., the current of the detection circuit) to the predetermined value included in Table 1 and determine the status of each fill port of the plurality of fill ports in this way, the controller may determine a status of all of the fill ports included in the imaging device.

[0038] In some examples, referring to Table 1 above, the controller 202 may identify the different combination of fill port statuses of the plurality of fill ports by comparing a predetermined value to Table 1. For example, referring to the Table 1 , when the controller 202 determines that the predetermined value of the of the detection circuit is 48, based on a value derived from detections by the current sensor the controller 202 may identify the status of a group of fill ports. For example, based on the predetermined value of 48, controller 202 can determine that the fill ports 104-1 , and 104-N are open and that the other fill ports (e.g., the fill ports 104-2, and 104-3) have a fill port status of closed. The fill ports being closed can further be determined to be either connected to a colorant container or dosed via a fill port cover, as is further described herein.

[0039] Continuing with this example, the controller 202 may determine that a portion of the group having a fill port status of dosed (e.g., the fill ports 104-2, and 104-3) may be further identified as sub-groups by determining if a portion of the closed fill ports are closed by being connected to a colorant container, or by a fill port cover. Said differently, the controller 202 may determine a sub-group within the group of closed fill ports; a first sub-group may be closed by a fill port cover and a second sub-group may be closed by a colorant container. In some examples, the controller 202 may identify the portions of the group of closed fill ports as a sub group where the switch corresponding to a particular fill port may be closed because the particular fill port is covered (e.g., closed) by a colorant container rather than the fill port cover.

[0040] For example, the memory resource 214 may store instructions which may be executed by the processing resource 212 to cause the controller 202 to determine whether a particular fill port is closed by a colorant container. The detection circuit may detect the presence of a colorant container by pulsing each of the plurality of fill ports with power to detect if the fill port is closed by a fill port cover, or by a colorant container. When a colorant container is defected by the controller 202, the controller 202 may query a memory device (e.g., container acumen) attached to the colorant container to further confirm the presence of the colorant container and detect information corresponding to the colorant container. The controller 202 may detect the presence of a colorant container by using a plurality of electrical contacts corresponding to each fill port of the plurality of fill ports. The electrical contacts are discussed in greater detail herein in conjunction with Figures 3, 4, and 5.

[0041] A controller 202 for fill port sensors according to the disclosure can include a memory resource 214 having instructions which may be executed by a processing resource 212 to cause the controller 202 to determine different combinations of fill port statuses and different sub-group statuses. Although the examples described in conjunction with Figure 2 referred to a current and a current sensor, it should be noted that similar operations may utilize a different detection element (e.g., a voltage change, a voltage ratio change, and/or an ADC value) as the predetermined value illustrated in Table 1. The different detection elements may correspond to the different fiii port statuses as described with respect to Figures 3, 4, and 5.

[0042] Figure 3 illustrates an imaging device 300 including a fill port 304 consistent with the disclosure. Figure 3 may illustrate an imaging device 300 comprising a fill port 304 having an open fill port status. Although not shown in Figure 1 for clarity and so as not to obscure examples of the disclosure, the imaging device 300 may include a plurality of fill ports, and the other elements of the imaging device 100 described in conjunction with Figure 1. As illustrated in Figure 3, the fill port 304 may include a plurality of contacts 316-1 ,... , 318-N. As used herein, the plurality of contacts 316-1 ,... , 318-N may be collectively referred to as the plurality of contacts 316. As used herein, the term“contacts” refers to an electrical circuit component comprising an electrically conductive material such that the material may communicatively couple to another electrical circuit component. As used herein, the term“communicatively coupled” refers to various wired and/or wireless connections between devices such that data and/or signals may be transferred in various directions between the devices.

[0043] Each of the plurality of contacts may be intended to serve a different purpose (e.g., a grounding reference point for a circuit, a contact to receive and transmit electrical power, a contact to detect the presence of a colorant container, a contact to receive data about a colorant container etc.). For example, the fill port 304 may have a plurality of contacts 316 that may communicatively couple to corresponding contacts of another element and/or device, and the controller (e.g., the controller 202) may determine a status of the fill port 304 depending on which of the contacts are communicatively coupled. For example, the contact 316-1 may be communicatively coupled to a power source included on the imaging device 300, and when the fill port 304 is covered by a corresponding fill port cover, the contact 316-1 may communicatively couple to the fill port cover via the resistor included in the corresponding fill port cover.

[0044] Although not shown in Figure 3 for clarity and so as not to obscure examples of the disclosure, the imaging device 300 may include detection circuit including a switch to correspond to each fill port. In the example illustrated in Figure 3, the fill port 304 has an open status. Said differently, the plurality of contacts 316 are not communicatively coupled to either a colorant container or a corresponding fill port cover. In this example, the switch corresponding to the fill port 304 may be open such that the resistor corresponding to the fii! port 304 is effectively

disconnected from the detection circuit as a result of a corresponding fill port cover being open. In this way, a current, a voltage change, or a change in resistance may be detected by various sensors included in the detection circuit. The controller may compare the predetermined value to a predetermined table (e.g., Table 1) to determine a status of the fill ports included in the imaging device 300. In some examples, a particular connector of the plurality of connectors 316 may be utilized to communicatively couple to a fill port cover and a different connector may be utilized to communicatively couple to a colorant container.

[0045] Figure 4 illustrates an imaging device 400 including a fill port 404 consistent with the disclosure. Although not shown in Figure 4 for clarity and so as not to obscure examples of the disclosure, the imaging device 400 may include a detection circuit and switches to correspond to each fill port of a plurality of fill ports. The imaging device 400 illustrated in Figure 4 includes a fill port 404, a

corresponding fill port cover 406, and a resistor 408 corresponding to the fill port cover 406. In this example, the fill port 404 is illustrated as having a closed status as the fill port cover 406 is engaged with the fill port 404. For example, the contact 416 1 may be a contact to receive and/or transmit electrical power, and the contact 416 N may be a grounding reference for the detection circuit included on the imaging device 400.

[0046] In some examples, the dosed status of the fill port 404 can indicate that the switch corresponding to the fill port 404 is closed, and the resistor 408 is communicatively connected to the detection circuit. Although not expressly illustrated by Figure 4, the fill port 404 may be one of a plurality of fill ports (e.g., the plurality of fill ports 104, previously described in connection with Figure 1). When the fill port 404 status is closed, a corresponding switch for fill port 404 is closed and the resistor 408 is connected to the detection circuit and the detection circuit may experience a change in voltage, change in voltage ratio, and/or a change in resistance which can be measured and compared to a predetermined value.

[0047] For example, the predetermined value may be determined by the controller (e.g., the controller 202) and compared to a predetermined table of predetermined values (e.g., such as Table 1 , previously described in connection with Figure 1). in this example, the controller may determine the status of each fill port of the plurality of fill ports included in the imaging device 400. The fill port 404 illustrated in Figure 4 may be included in a group of fill ports having a fill port status of dosed. Further, the fill port 404 may be categorized as included in a sub-group of the plurality of fill ports where the fill port 404 is closed by a corresponding fill port cover 406. Conversely, the fill port such as the fill port 404 may be included in a different sub-group where the fill port 404 is closed by a colorant container rather than a corresponding fill port cover 406, as described in conjunction with Figure 5.

[0048] Figure 5 illustrates an imaging device 500 including a fill port 504 consistent with the disclosure. Although not shown in Figure 5 for clarity and so as not to obscure examples of the disclosure, the imaging device 500 may include a controller, and a detection circuit including a switch that corresponds to each fill port of a plurality of fill ports. The imaging device 500 illustrated in Figure 5 includes an example fill port 504, where the status of the fill port 504 is closed by a colorant container 518. The colorant container 518 can include a colorant acumen 520. In some examples, the plurality of contacts 516 may communicatively couple to elements included on the colorant container acumen 520.

[0049] For example, as described above in connection with Figure 4, the contact 516-1 may be a contact to receive and/or transmit electrical power, and the contact 516-N may be a grounding reference for the detection circuit included in the imaging device 500. In the example illustrated in Figure 5, the presence of the colorant container 518 may close the switch corresponding to the fill port 504, thus changing a determined value (e.g., determined current, determined voltage etc.) of the detection circuit. Although not expressly illustrated by Figure 5, the fill port 504 may be one of a plurality of fill ports (e.g., the plurality of fill ports 104), and each of the plurality of fill ports may have a different fill port status. When the fill port 504 status is closed, the switch corresponding to fill port 504 is closed, and the detection circuit may experience a change in voltage, a change in current, and/or a change in resistance. Additionally, because there is a plurality of fill ports included in the imaging device 500, the signal change may result in a determined value that the controller may compare to the predetermined table (e.g., Table 1 , as previously described in connection with Figure 1) to determine the fill port status of each fill port.

[0050] For example, the predetermined value may be determined by the controller (e.g., the controller 202) and compared to a predetermined table such as Table 1 described above. In this example, the controller may determine the status of each fill port of the plurality of fill ports included in the imaging device 500. The fill port 504 illustrated in Figure 5 may be included in a group fill ports where the status of the fill port 504 is dosed. Further, the fill port 504 may be may be categorized as included in a sub-group of the plurality of fill ports where the fill port 504 is closed by a colorant container 518. A fill port such as the fill port 404, previously described in connection with Figure 4, may be included in a different sub-group where the fill port 404 is closed by a corresponding fill port cover 406 rather than the colorant container 518. The detection circuit may detect that a colorant container 518 is present by pulsing the fill port 504.

[0051] For example, the contact 516-2 may be a contact that is

communicatively coupled to the container acumen 520 of the colorant container 518 and also communicatively coupled to an acumen sensor (not expressly illustrated) included in the detection circuit of the imaging device 500. in this way, when the controller determines that the fill port 504 has a status of closed, the controller can determine how the fill port 504 is closed. For example, the controller can determine that fill port 504 is closed by a fill port cover or closed by a colorant container 518.

[0052] In some examples, the controller may also obtain data about the colorant container 518 (e.g., the color of the print substance, the position of the colorant container etc.). For example, the contact 516-3 of the fill port 504 may be communicatively coupled to the container acumen 520 and to a colorant container data sensor included in the detection circuit. In this way, the controller may communicate the colorant controller data to the imaging device 500 such that it may be communicated to a user or an imaging device manager. The acumen sensor and the colorant container data sensor are discussed in more detail herein in conjunction with Figures 6 and 7.

[0053] Figure 6 illustrates an example of a detection circuit 610 of an imaging device consistent with the disclosure. Although not shown in Figure 6 for clarity and so as not to obscure examples of the disclosure, the detection circuit 610 may be included in an imaging device (e.g., imaging device 100) and may include a controller (e.g., the controller 210). As illustrated in Figure 6, the detection circuit 610 may include a plurality of resistors 608. Although not shown in Figure 6 for clarity and so as not to obscure examples of the disclosure, the plurality of resistors 608 may correspond to a plurality of fill port covers (e.g., the plurality of fill port covers 106). The detection circuit 610 may also include a plurality of contacts 616. Although not shown in Figure 6 for clarity and so as not to obscure examples of the disclosure, the plurality of contacts 616 may correspond to a plurality of fill ports (e.g., the plurality of fill ports 104). As illustrated in Figure 6, the detection circuit 610 may include a plurality of switches 622-1 ,... , 622-N. As used herein, the plurality of switches 622-1 , 622-N may be collectively referred to as the plurality of switches 622. Each switch of the plurality of switches 622 may correspond to a fill port, and each switch of the plurality of switches 622 may be open when the fill port of which the particular switch corresponds is open. Each switch of the plurality of switches 622 may be closed when the fill port of which the particular switch it corresponds to is dosed. In some examples, the plurality of switches 622 may be connected to a power supply 624.

[0054] As used herein, the term“power supply” refers to an electrical or mechanical device that may supply electric power to an electrical load in some examples, electric power may be supplied to each switch of the plurality of switches 622 by the power supply 624. For example, when a particular switch 622-1 is closed, the corresponding resistor 608-1 may be effectively connected to the detection circuit via the contact 616-1. in response to the switch 622-1 being dosed, the detection circuit may experience a change in resistance which may be detected by the current sensor 626. In this example, the detected current may be

extrapolated into a determined value and compared to a predetermined value include in a predetermined table (e.g., Table 1) by the controller included in the imaging device. Said differently, the status of a fill port may be determined based on the comparison of the determined current and the predetermined table of

predetermined values in some examples, the controller may further determine if the switch 622-1 is closed in response to a corresponding fill port cover, or by a colorant container.

[0055] For example, each switch of the plurality of switches 622 may be connected to a respective control signal of a plurality of control signals 634-1 ,... , 634-N. As used herein, the term“control signal” refers to a time-varying quantity of voltage to pulse a fill port. The plurality of control signals 634-1 ,... , 634-N may be collectively referred to as the plurality of control signals 634. The plurality of control signals 634 may pulse each fill port of the plurality of fill ports to determine if any of the plurality of contacts 616 are connected to a colorant container. For example, the control signal 634-1 may pulse electric power to the switch 622-1 , and if the switch 622-1 is closed, the pulsed power may be transmitted to the plurality of contacts 616. Continuing with the previous example, if a colorant container (e.g., the colorant container 518) is connected to the particular fill port the contact 618-2 may detect a container acumen (e.g , the container acumen 520) and transmit the container acumen detection to an acumen sensor 630. As used herein, the term“acumen sensor” refers to a component of the detection circuit 610 that may detect the presence of a colorant container and may alert the controller to the presence of the colorant container in some examples, the acumen sensor 630 may be a function of hardware and/or firmware included in the controller of the imaging device in some examples, the acumen sensor 630 may be a separate component included in the detection circuit 610. The acumen sensor 630 may collect data about the colorant container such that it may be communicated to the controller. In some examples, the presence of the colorant container at the particular fill port may be further verified by the controller collecting data about the colorant container in this way, the detection circuit 610 may communicate this data to the imaging device to be used to provide guidance to a user.

[0058] Figure 7 illustrates an example detection circuit 710 of an imaging device consistent with the disclosure. Although not shown in Figure 7 for clarity and so as not to obscure examples of the disclosure, the detection circuit 710 may be included in an imaging device (e.g., imaging device 100) and may include a controller (e.g., the controller 210). As illustrated in Figure 7, the detection circuit 710 may include a plurality of resistors 708. Although not shown in Figure 7 for clarity and so as not to obscure examples of the disclosure, the plurality of resistors 708 may correspond to a plurality of fill port covers (e.g., the plurality of fill port covers 106). The detection circuit 710 may also include a plurality of contacts 716. Although not shown in Figure 7 for clarity and so as not to obscure examples of the disclosure, the plurality of contacts 716 may correspond to a plurality of fill ports (e.g., the plurality of fill ports 104). As illustrated in Figure 7, the detection circuit 710 may include a switch 722, which may be closed when the detection circuit is making a measurement to determine a fill port status and open when a measurement is not being taken. In this way, the switch 722 may be used to isolate the portion of the detection circuit 710 corresponding to each fill port of the plurality of fill ports for the purpose of saving power or preventing leakage current, which could cause corrosion on the plurality of contacts 716 if power is applied for an extended duration. The switch 722 may be controlled by the controller using control signal 734. For example, when switch 722 is dosed, a corresponding resistor 708-1 may be effectively connected to the detection circuit 710 via the contact 716-1. in response to the switch 722 being closed, the detection circuit 710 will measure a voltage which may be detected by an ADC 728.

[0057] In some examples, each of the plurality of resistors 708 may have a different resistance value and electric power may be supplied to each switch of the plurality of switches 722, by the power supply 724. For example, when a particular switch 722-1 is closed, the corresponding resistor 708-1 may be effectively connected to the detection circuit via the contact 716-1. In response to the switch 722-1 being closed, the detection circuit may experience a change in resistance which may be detected by an ADC 728. In this example, when a power is applied to the detection circuit 710 by the power supply 724, the change in resistance may change a voltage divider ratio by a pull-down resistor 736, and the resulting change in voltage ratio may be measured (and/or detected) by the ADC 728. In this example, the detected change in the voltage ratio may be a detected value and compared to a predetermined table (e.g., table 1} by the controller included in the imaging device. Said differently, the status of a fill port may be determined based on the comparison of the determined voltage divider ratio and the predetermined table of predetermined values in some examples, the controller may further determine if the switch 722-1 is closed in response to a corresponding fill port cover, or by a colorant container.

[0058] For example, electric power may be pulsed to the switch 722-1 , and if the switch 722-1 is closed, the pulsed power may be transmitted to the plurality of contacts 716. Continuing with the previous example, if a colorant container (e.g., the colorant container 518) is connected to the particular fill port, the contact 716-2 may detect a container acumen (e.g., the container acumen 520) and transmit the container acumen detection to an acumen sensor 730. in some examples, the presence of the colorant container in the particular fill port may be further verified by the controller collecting data about the colorant container. The electric power may be pulsed to the contact 716-3, and if a colorant container is present the detection circuit 710 may transmit the data related to the colorant container to a colorant container sensor 732.

[0059] Fill port sensors according to the disclosure can detect a status of a plurality of fill ports. This example detection circuit 710 may protect the imaging device and the print substance contained therein by alerting a user to the status of the fill port as being open, closed, or connected to a colorant container in this way, the integrity of the fill ports and the print substance may be monitored and maintained. Figures 3, 4, and 5 illustrate an example fill port status consistent with this disclosure. The controller may determine via a plurality of contacts included on each fill port if the fill port is open (Figure 3), closed via a fill port cover (Figure 4), or via a colorant container (Figure 5). The controller may further pulse the fill port with an electric power to determine information about the colorant container from a container acumen. The determined status of the fill ports may be used by the imaging device to protect the contents of the print substance reservoir from environmental elements. Further, the controller may communicate this information to a user via a user interface to provide guidance or warning to regarding a status of a fill port.

[0060] In the foregoing detailed description of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration how examples of the disclosure may be practiced. These examples are described in sufficient detail to enable those of ordinary skill in the art to practice the examples of this disclosure, and it is to be understood that other examples may be utilized and that process, electrical, and/or structural changes may be made without departing from the scope of the disclosure.

[0061] The figures herein follow a numbering convention in which the first digit corresponds to the drawing figure number and the remaining digits identify an element or component in the drawing. Similar elements or components between different figures may be identified by the use of similar digits. For example, 102 may reference element“02” in Figure 1 , and a similar element may be referenced as 202 in Figure 2.

[0062] Elements illustrated in the various figures herein can be added, exchanged, and/or eliminated so as to provide a plurality of additional examples of the disclosure. In addition, the proportion and the relative scale of the elements provided in the figures are intended to illustrate the examples of the disclosure and should not be taken in a limiting sense. As used herein, the designator“N”, particularly with respect to reference numerals in the drawings, indicates that a plurality of the particular feature so designated can be included with examples of the disclosure. The designators can represent the same or different numbers of the particular features. Further, as used herein, "a plurality of an element and/or feature refers to more than one of such elements and/or features.

[0083] The above specification, examples and data provide a description of the method and applications and use of the system and method of the present disclosure. Since many examples can be made without departing from the spirit and scope of the system and method of the present disclosure, this specification merely sets forth some of the many possible example configurations and implementations.