Abstract: There is provided a method of testing an RF transceiver circuit and an RF transceiver circuit arranged to be operable in a test mode comprising a transmitter circuit portion and a receiver circuit portion, the receiver circuit portion including a mixer. The method involves the transmitter circuit portion generating a modulated signal and the receiver circuit portion receiving a continuous radio frequency wave. The mixer mixes the modulated signal with a signal derived from the continuous radio frequency wave to produce an output. A remainder of the receiver circuit portion processes the output of the mixer.

Abstract: An oscillator arrangement is provided, comprising a relaxation oscillator having an active state and an inactive state; a bias current circuit portion arranged to provide a bias current to the relaxation oscillator during said active state; and an electronic switch arranged to isolate said relaxation oscillator from the bias current circuit portion when in said inactive state. The oscillator arrangement is arranged to store an internal voltage value associated with said bias current and the bias current circuit portion is arranged to use the stored internal voltage value to generate the bias current when the oscillator is started up from the inactive state to the active state.

Abstract: A control portion for controlling an amplifier portion of a transmitter device is provided. The amplifier portion is arranged to amplify a radio signal with a transmission gain based at least partially on a gain control signal and having a nominal gain relationship between the gain control signal and the transmission gain. The control portion is arranged to determine a desired transmission gain, to determine one or more operating conditions, to calculate a gain control signal for causing the amplifier portion to apply the desired transmission gain, taking into account the nominal gain relationship and the one or more operating conditions, and to output said gain control signal. The gain control signal is different to a gain control signal calculated based only on the nominal gain relationship.

Abstract: An electronic device comprising a system on chip and an external module. The system on chip includes a plurality of internal subsystems and a power management system including a plurality of internal voltage regulators which supply power to the plurality of internal subsystems. Each of the internal voltage regulators has an associated current limiter. The external module includes at least one external voltage regulator which can provide power to at least one of the internal subsystems. The power management system during a start-up phase enables the internal voltage regulators and the current limiters and in a subsequent phase determines an externally powered set of the internal subsystems, disables the corresponding internal voltage regulators, and disables the current limiters associated with the internal subsystems not externally powered.

Abstract: A method of digital radio communication between a first device and a second device is disclosed. An advertising packet is transmitted between first and second devices, wherein the packet includes a first address and a data portion. Additionally, an encryption key is transmitted between the devices. The first device generates a second address by encrypting an identity value derived from part of the first address using the encryption key and the data portion. The result is encrypted to generate second portion of the second address. The first device then transmits a connection request including the second address. The second device decrypts the second portion and uses the encryption key to determine correspondence with the first portion. If said correspondence is determined, the second device decrypts the first portion using at least the encryption key and compares it to an expected identity value derived from the first address.

Abstract: A circuit portion comprising a clock domain is disclosed. A first clock is arranged to clock components in the clock domain. An analogue to digital converter is clocked by a second clock with a duty cycle. The second clock is derived from the first clock. The analogue to digital converter is arranged to output a feedback signal upon finishing a conversion of a sample, and the feedback signal is arranged to control the duty cycle.

Abstract: A radio transmitter is configured to operate in accordance with a first predetermined OFDM radio protocol. The transmitter reserves, within a timeslot with a predetermined timeslot duration, a reserved set of time-frequency resource units not available for an OFDM data channel defined by the first protocol. The transmitter allocates, within the timeslot, an allocated set of R time-frequency resource units for the OFDM data channel defined by the first protocol, wherein a number M of time-frequency resource units are included in both the allocated set and the reserved set, wherein the value R is such that R>N and R?M?N, where N is a predetermined maximum number of time-frequency resource units that can be used to carry the data channel. The transmitter then transmits data indicative of the allocated set of R time-frequency resource units and data indicative of the reserved set of time-frequency resource units.

Abstract: A digital radio transmitter device operates in accordance with a predetermined communication protocol that defines a default inter-frame spacing. The device has a minimum inter-frame spacing that is shorter than said default inter-frame spacing. The device is configured to: transmit a first data packet indicating that the device is able to support an inter-frame spacing shorter than said default inter-frame spacing; receive a second data packet from a peer device after said default inter-frame spacing; if said second data packet indicates that said peer device is able to support an inter-frame spacing shorter than said default inter-frame spacing, transmit a third data packet using an inter-frame spacing shorter than said default inter-frame spacing; and if said second data packet does not indicate that said peer device is able to support an inter-frame spacing shorter than said default inter-frame spacing, transmit said third packet using said default inter-frame spacing.

Abstract: An integrated-circuit chip and method of operating said chip is provided. The integrated-circuit chip includes multiple processors, a system memory and a main system bus for carrying data between each of the processors and the system memory. The chip also has debug logic, a debug port for communicating with the debug logic from outside the chip and a debug connection that connects the debug logic to the main system bus. A power management system is also included for controlling the power supplied to each of a number of power domains on the chip. The debug logic and each of the processors are in different respective power domains. The debug logic is configured to send a debug instruction to any of the processors. The debug instruction is communicated over the debug connection and over the main system bus.

Abstract: A circuit portion comprises a DCDC converter that is configured to charge and discharge an inductor according to a duty cycle to provide current to an output load. A duty module is configured to determine the duty cycle such that the DCDC converter will output a target current. A duty limiter module is configured to cause the inductor to discharge early if the determined duty cycle exceeds a threshold.

Abstract: According to an aspect, there are provided an apparatus and a method for providing an access to a memory circuit. A read enable input initializing a wait state counter configured to count a predetermined number of clock cycles is received (200) and the wait state counter output is monitored. A memory ready signal output is received (202) from the memory circuit at a synchronizer input and the output signal of the synchronizer is monitored. An ON-state data ready signal is provided (204) when either the wait state counter has elapsed, or the output signal of the synchronizer is in ON-state.

Abstract: An amplitude regulator circuit portion is arranged to supply a current to an inverter in an oscillator circuit. The regulator monitors a voltage at the input terminal of the inverter and varies the current supplied to the inverter in response to the monitored voltage. The amplitude regulator comprises first, second, and third PMOS transistors, and first and second NMOS transistors and is arranged such that an input node is connected to the input terminal of the inverter, a respective gate terminal of each of the first and second NMOS transistors, and a respective drain terminal of the first NMOS and first PMOS transistors. The amplitude regulator also comprises a back-bias circuit portions arranged to vary a back-bias voltage at a back-gate terminal of the second NMOS transistor, to vary a threshold voltage, where the threshold voltage of the second NMOS transistor is lower than that of the first NMOS transistor.

Abstract: There is disclosed an electronic device and a method of operating an electronic device. It has peripherals which each have one or more event outputs or task inputs, connected to a peripheral interconnect. The device also has a controller for configuring the peripheral interconnect and a memory, which are communicatively coupled to a bus system. The peripheral interconnect receives configuration data from the controller, which selectively connects peripheral event outputs and task inputs. The controller uses the bus system to access a sequence of instructions in a script stored in the memory. Each instruction in the sequence identifies a peripheral task input, event output and a second peripheral event output. Each subsequent instruction in the sequence is implemented in response to detecting an event signalled from the second peripheral event output identified by the preceding instruction in the sequence.

Abstract: An integrated circuit device includes an n-bit register comprising: a plurality of latches and at least one flip-flop, and clock gating circuitry, which includes a clock signal coupled to the latches and the flip-flop. Each latch comprises a latch gating terminal configured to receive a gating signal, wherein a respective latch is configured to receive the gating signal that either corresponds to the clock signal or is determined according to a logical operation including the clock signal such that a transparency for each respective latch is controlled in dependence upon a level of the gating signal. The integrated circuit device is configured to operate in a scan test mode, wherein during a scan shift operation, an input signal terminal of the flip-flop is configured to receive a test input signal and the flip-flop is configured to load the test input signal to an output signal terminal of the flip-flop.

Abstract: A radio receiver comprises a matched filter bank and a decision unit. The matched filter bank has a plurality of filter modules for generating correlation-strength data from a sampled radio signal, each filter module being configured to cross-correlate the sampled signal with data representing a respective filter sequence. The decision unit is configured to use the correlation-strength data to generate a sequence of decoded symbols from the sampled signal. The matched filter bank and/or decision unit are configured to determine the value of each symbol in the sequence in part based on the value of a respective earlier decoded symbol from the sequence of decoded symbols.

Abstract: A microcontroller system comprising a master microcontroller unit, a further module and a general purpose input/output. In a first state the general purpose input/output is controlled by the master microcontroller unit and in a second state the general purpose input/output is controlled by the further module. The master microcontroller unit is arranged to transmit a selection signal which changes the state of the general purpose input/output.

Abstract: A computer system configured to enable communication between two or more virtual platforms is disclosed. The computer system comprises a physical processor configured to run the two or more virtual platforms. The computer system further comprises a memory. The memory comprises one or more separate memory portions allocated to each of the two or more virtual platforms, wherein within at least one memory portion allocated to one of the virtual platform a predefined range of addresses is configured as a shared device memory, the shared device memory being accessible by all the virtual platforms. Firmware running on a first virtual platform is configured to transfer a data packet from the first virtual platform to one or more further virtual platforms via the shared device memory.

Abstract: An electronic device comprises an oscillator circuit portion comprising an inverter and a crystal oscillator connected between the input and output terminals of the inverter. An amplitude regulator circuit portion is arranged to supply a current to the inverter. The amplitude regulator monitors a voltage at the input of the inverter and varies the current supplied to the inverter in response to the monitored voltage. The amplitude regulator comprises a trimmable resistor arranged such that the voltage at the input of the inverter is set to an operating point when the supply current is equal to a threshold value, the operating point being at least partly determined by the selected resistance of the resistor. A current monitor is arranged to monitor the current supplied to the inverter during operation and to determine therefrom whether the voltage at the input terminal of the inverter is within a predetermined range.

Abstract: A method of determining a distance between a radio frequency device and a target is disclosed in which the radio frequency device receives a radio frequency signal from the target. The method comprises determining a time domain channel response from the received radio frequency signal, determining an amplitude of a largest peak in the time domain channel response, determining an amplitude of a second, earlier, peak in the time domain channel response, comparing the second peak amplitude to a threshold based on the largest peak amplitude, identifying the largest peak as a shortest path peak if the second peak amplitude is less than the threshold, identifying the second peak as a shortest path peak if the second peak amplitude is greater than the threshold, and calculating the distance between the radio frequency device and the target based on a time corresponding to the shortest path peak.

Abstract: A circuit portion comprises a DCDC converter that provides current to one of a plurality of loads at a time. A controller detects when a voltage across an under-supplied load of the plurality of loads is below a first threshold. Channel logic circuitry provides current from the converter to the under-supplied load in response to the controller detecting that the voltage is below the first threshold. A voltage regulator provides current to the under-supplied load when the voltage is below a second threshold.