Abstract:
Pulse amplitude modulation (PAM) encoding for a communication bus is disclosed. In particular, various two-wire communication buses may encode bits using three-level PAM (PAM-3) or five-level PAM (PAM-5) to increase bit transmission without requiring increases to clock frequencies or adding additional pins. Avoiding increases in clock frequencies helps reduce the risk of electromagnetic interference (EMI), and avoiding use of extra pins avoids cost increases for integrated circuits (ICs).
Abstract:
Systems, methods, and apparatus for communication over a serial bus in accordance with an I3C protocol are described that enable a slave device to request that a bus master device terminate a write transaction with the slave device. The serial bus may be operated according to an I3C single data rate protocol. In various aspects of the disclosure, a method performed at a master device coupled to a serial bus includes initiating a write transaction between the master device and a slave device, where the write transaction includes a plurality of data frames, and at least one data frame is configured with a transition bit in place of a parity bit. The method may include terminating the write transaction when the slave device drives a data line of the serial bus while receiving the transition bit.
Abstract:
Systems, methods, and apparatus for communicating virtual GPIO information generated at multiple source devices and directed to multiple destination devices. A method performed at a device coupled to a serial bus includes generating first virtual GPIO state information representative of state of one or more physical GPIO output pins, asserting a request to transmit the first virtual GPIO state information by driving a data line of the serial bus from a first state to a second state after a start code has been transmitted on a serial bus and before a first clock pulse is transmitted on a clock line of the serial bus, transmitting the first virtual GPIO state information as a first set of bits in a data frame associated with the start code, and receiving second virtual GPIO state information in a second set of bits in the data frame.
Abstract:
Systems, methods, and apparatus are described that enable communication of in-band reset signals over a serial bus. A method performed at a slave device coupled to the serial bus includes configuring a reset controller to operate in one of plural modes, identifying a first reset pattern in signaling received from a multi-wire serial bus, complying with one or more transmissions defined by the protocol, asserting a reset input of a processing circuit in the slave device responsive to an identification of the first reset pattern when the reset controller is operated in a first mode, and ignoring the first reset pattern when the reset controller is operated in a second mode. The signaling received from the multi-wire serial bus may include one or more transmissions defined by a protocol used on the multi-wire serial bus. The reset controller may operate autonomously from the processing circuit in the first mode.
Abstract:
Disclosed are methods and apparatus for transmitting sensor timing correction messages with a host controller. The methods and apparatus determine synchronization messages that are transmitted to a sensor coupled with the host controller via an interface, where the messages indicate a beginning of a synchronization period for synchronizing timing of the host controller and the sensor. Additionally, a delay time message is determined that indicates a time delay between the beginning of the synchronization period and an actual transmission time of the synchronization message. The synchronization message is transmitted with the delay time message in an information message to the sensor, where information message is configured to allow the sensor to correct timing of a sensor timer by accounting for the delay time.
Abstract:
Embodiments of the invention provide for a sensor system with enhanced low-power features. Embodiments can include transmission of sensor data from a transmitter unit to a receiver unit. The sensor data can flag the sensor data with a particular header ID, enabling the receiver unit to route the sensor data to a low-power processing unit within the receiver unit without using the receiver unit's higher-power application processer. Embodiments can also utilize a proprietary encryption engine to provide a supplementary encryption layer to any encryption utilized in the wireless protocol. The transmitter unit can also compress and batch the sensor data for sending, to further increase power savings.
Abstract:
Methods, systems, computer-readable media, and apparatuses for assessing a fitness state of a user via a mobile device are presented. In some implementations, a first physiological measurement of the user during a first level of a physical activity is obtained via one or more sensors. A second physiological measurement during a second level of the physical activity is obtained via the one or more sensors. A transient physiological measurement based on the first physiological measurement and the second physiological measurement is determined. The physical activity is classified based on one or more motion measurements obtained via the one or more sensors. A fitness profile indicative of a fitness state of the user is generated based at least in part on the determined transient physiological measurement and the classified physical activity.
Abstract:
Disclosed is an apparatus and method for automatically configuring a mobile device for collecting and inferring heart rate data of a user. The method may include capturing heart rate data for a user with a heart rate sensor that is coupled with a mobile device. The method may also include monitoring a activity state of the user from activity data captured by the mobile device, and detecting a constant activity state of the user. The method may also include inferring heart rate data for the user from the captured heart rate data during a period in which the user remains in the constant activity state. The method may also include providing the inferred heart rate data, as captured heart rate data, to a heart rate calculator during the period in which the user remains in the constant activity state.
Abstract:
A device is provided that has a bus including a first line and a second line. A first set of devices are coupled to the bus and, in a first mode of operation, configured to use the first line for data transmissions and use the second line for a first clock signal. One or more additional lines are connected between two or more of the devices in the first set of devices for transmitting signaling between the two or more devices. A second set of devices are configured to use the bus and at least one of the additional lines for data transmissions in a second mode of operation, where in the second mode of operation symbols are encoded across the first line, the second line, and the at least one of the additional lines.
Abstract:
Systems, methods and apparatus are described that offer improved performance of a sensor bus. A first command is transmitted to devices coupled to a serial bus operated in a first mode in accordance with a first protocol to cause the serial bus to be operated in a second mode. After communicating in accordance with a second protocol while the serial bus is operated in the second mode, a second command is transmitted to the plurality of devices in accordance with the first protocol to terminate the second mode. In the second mode, extra symbols inserted into a sequence of symbols transmitted on the serial bus prevent the occurrence of an unintended signaling state on the serial bus. Pulses transmitted on a wire of the serial bus in the second mode may have their duration limited such that a filter of a second device suppresses the limited-duration pulses.