Abstract:
An apparatus and method are provided for testing integrated circuits. An integrated circuit arrangement is provided having first and second dice. Each die has circuitry for diagnostic testing in response to a diagnostic test signal. The circuitry further defines an input for receiving the diagnostic test signal and an output for transmitting results of the diagnostic testing for each of the dice. Interconnecting circuitry between the dice transmits the diagnostic test signal transmitted to the first die to the second die before the diagnostic testing is completed in the first die.
Abstract:
The present invention provides a seating apparatus having an adjustable level of firmness. The seating apparatus comprises a base, an inflatable element arranged on the base, and a cover covering the inflatable element. Access means in communication with the inflatable element are provided, enabling inflation of the inflatable element for providing an adjustable firmness in the seating area. The inflatable element may comprise a ring having a center opening. The base may comprise a ring having a center opening coinciding with the center opening of the inflatable element. The cover may comprise a section of permeable material over the center opening. A fan may be affixed within the center opening for providing airflow through the center opening.
Abstract:
An integrated circuit having a serial data input pin and a serial data output pin, on-chip functional circuitry comprising at least two processing cores, a data adaptor which is in communication with the processing cores by respective communication channels and is connectable to the input and output pins. The data adaptor includes transmit circuitry, including circuitry for receiving parallel data and control signals from on-chip functional circuitry and circuitry for converting parallel data and control signals into a sequence of serial bits including flow control bits, data bits and channel identification bits that identify the communication channel on which parallel data and control signals were received. The adaptor further includes receive circuitry having circuitry for receiving from off-chip via the serial data input pin a sequence of serial bits including flow control bits, data bits and channel identification bits, circuitry for converting the bit sequence into parallel data and control signals for the on-chip functional circuitry and circuitry for transmitting parallel data and control signals on the communication channel identified by said channel identification bits.
Abstract:
There is disclosed a single chip integrated circuit device comprising an instruction trace controller operable to monitor an address in memory of instructions to be executed by an on-chip CPU. The instruction trace controller is connected to trace storage locations for causing selected ones of said addresses to be stored at said trace locations, dependent upon detection that one of said addresses is not the next sequential address in memory after the previous one of the addresses. There is also disclosed a method of providing an instruction trace from an on-chip CPU within a single chip integrated circuit device in which addresses in memory of instructions to be executed by the CPU are held sequentially in an instruction pointer register. The addresses are monitored by an instruction trace controller, which is operable to cause selected ones of the address to be stored at a predetermined trace storage location dependent on detection that one of the addresses is not the next sequential address in memory after the previous one of the addresses.
Abstract:
There is disclosed a test access port controller for effecting communications across a chip boundary having a test mode and a diagnostic mode of operation, wherein in the test mode of operation the test data is resultant data from a test operation having an expected and time delayed relationship, and in the diagnostic mode of operation diagnostic data is conveyed both on and off chip in the form of respective independent input and output serial bit streams simultaneously through the test access port controller.
Abstract:
There is disclosed a single chip integrated circuit device having a bus system, functional circuitry, and external port, and a parallel/serial data packet converter interconnecting the bus system and the external port. The parallel/serial data packet converter is operable to convert parallel data from the bus system into bit serial packets for output through the port, and allocate a packet identifier to the bit serial packets in dependence on the information received from the bus system in accordance with a predetermined protocol. A method of effecting communication between a single chip integrated circuit device and an external device using such a parallel/serial data packet converter is also disclosed.
Abstract:
A test access port controller is provided for implementing scan testing with a chain of scan latches on an integrated circuit. The test access port controller can implement a structural test or a performance test. Selection between the two types of test is achieved through logic circuitry of the test access port controller. An integrated circuit and a test system are also provided.
Abstract:
A method of testing the performance of a combinational logic circuit is described. In contrast to a structural test which verifies the operation of the combinational logic circuitry, a performance test allows the performance of a combinational logic circuit to be tested by determining the accuracy of a set of outputs resulting from a change in input bits to the combinational logic circuit. Thus, it is possible to monitor more closely performance aspects, such as the maximum delay from input to output of a combination logic circuit.
Abstract:
A scan latch is described which comprises a capture half-latch, a release half-latch and an update half-latch. The capture half-latch has an input terminal connected to receive an input signal, a control terminal connected to a clock signal, and an output terminal. The release half-latch and update half latch each have an input terminal fixedly connected to the output terminal of the capture half latch. The release half-latch also has a control terminal connected to a clock signal and an scan output terminal. The update half-latch also has a control terminal connected to a clock signal and a data output terminal. The combination of the capture half-latch and one of the update half-latch and the release half-latch acts as a full-latch. The combination of these half-latches allows for simplified circuitry for testing integrated circuits. Clock signals provided to the half-latches can be different clock signals, and their timing can be individually controlled. This scan latch comprising half-latches can be used in place of any full-latch where a scan test is to be carried out and where a functional data output should not change while scan data is being shifted in or out. Furthermore, a scan latch according to this invention is also able to carry out a performance test to test the timing of logic circuitry. A method of using the scan latch to carry out a structural test of a circuit is also described.
Abstract:
A half-latch for a scan latch is described. The half-latch has an input terminal for receiving an input signal a first control terminal for receiving a clock signal and an output terminal. When enabled, the half-latch adopts a data transfer state in which it transmits a signal from its input terminal to its output terminal. Alternatively, the half-latch can adopt a data holding state in which a signal is stored on the output terminal, these states being selected in dependence on the state of the clock signal. The half-latch described herein has a second control terminal which receives the control signal to selectively disable the half-latch. This allows a common clock signal to be used when a scan latch is constructed using these half-latches.