Abstract: An example printing device may comprise an indicator to convey information to a user, a print substance reservoir to house a print substance, where the print substance reservoir is communicatively coupled to a fill port, a sensor to determine when a refill container is connected to the fill port, a processing resource, and a non-transitory machine-readable medium storing instructions executable by the processing resource to transmit signals to the indicator responsive to an indication that the sensor has detected the refill container connected to the fill port, where the signals correspond to the information to be conveyed by the indicator, and authenticate the refill container.

Abstract: A print substance container includes a print substance reservoir, a flange, and sensor system. The print substance reservoir includes a set of walls including an upstanding wall and a base. The set of walls enclose an interior of the print substance reservoir. The flange is remote from the interior of the print substance reservoir. The sensor system includes a level sensor, a reference full sensor, and a reference empty sensor. The level sensor is attached to the upstanding wall opposite the interior of the print substance reservoir. The reference full sensor is attached to the base opposite the interior of the print substance reservoir. The reference empty sensor is attached to the flange.

Abstract: Reducing power consumption of an electrical device is provided. The electrical device includes a first and a second module. The first and second modules include a first and a second memory, and a first and second system on chip (SoC) respectively. The first and second SoCs include a first and a second micro-processor respectively. A PCI-e bus connects the modules. The second module enters a sleep mode state that includes a first and a second sleep mode. The second module transitions between the first and second sleep modes while in the sleep mode state. The second SoC reduces a power state of the second module during the first sleep mode, and powers off the second SoC during the second sleep mode.

Abstract: An example printing device may comprise an indicator to convey information to a user, a print substance reservoir to house a print substance, where the print substance reservoir is communicatively coupled to a fill port, a sensor to determine when a refill container is connected to the fill port, a processing resource, and a non-transitory machine-readable medium storing instructions executable by the processing resource to transmit signals to the indicator responsive to an indication that the sensor has detected the refill container connected to the fill port, where the signals correspond to the information to be conveyed by the indicator, and authenticate the refill container.

Abstract: Reducing power consumption of an electrical device is provided. The electrical device includes a first and a second module. The first and second modules include a first and a second memory, and a first and second system on chip (SoC) respectively. The first and second SoCs include a first and a second micro-processor respectively. A PCI-e bus connects the modules. The second module enters a sleep mode state that includes a first and a second sleep mode. The second module transitions between the first and second sleep modes while in the sleep mode state. The second SoC reduces a power state of the second module during the first sleep mode, and powers off the second SoC during the second sleep mode.

Abstract: A circuit includes a pulse generator to generate an output pulse in response to a signal representing rotation of a fan. A timing relationship between output pulses represents speed of the fan. A filter circuit converts the output pulse to a direct current (DC) voltage signal proportional to the speed of the fan. A monitor circuit monitors the DC voltage signal with respect to a predetermined threshold and generates a control signal that disables a printer dryer if the DC signal does not satisfy the predetermined threshold.

Abstract: A circuit includes a pulse generator to generate an output pulse in response to a signal representing rotation of a fan. A timing relationship between output pulses represents speed of the fan. A filter circuit converts the output pulse to a direct current (DC) voltage signal proportional to the speed of the fan. A monitor circuit monitors the DC voltage signal with respect to a predetermined threshold and generates a control signal that disables a printer dryer if the DC signal does not satisfy the predetermined threshold.