Stmicroelectronics International N.v.

Stmicroelectronics Application Gmbh

Stmicroelectronics S.r.l.

Avneep Kumar Goyal

Venkata Narayanan Srinivasan

Balwinder Singh Soni

Thomas Szurmant

Nicolas Bernard Grossier

Deepak Baranwal

Satinder Singh Malhi

Amritanshu Anand

Misaele Marletti

Alessandro Daolio

Anubhav Arora

In general, trace and debug logic should not be affected by all functional or destructive resets of a processing system. However, certain events, such as power supply related events may be utilized to reset the trace and debug logic since the trace and debug logic may cease correct operation if the provided power supply is insufficient. In addition, it may be beneficial for a debugger to initiate requests to reset trace and debug logic. Further, fault triggers from critical path monitors may be candidates as a source of reset for the trace and debug circuitry. For example, when critical path monitors trigger a fault, the fault may be from the logic associated with either trace and debug logic or the logic which is being debugged or traced. As such, in some instances both trace and debug circuitry and the processing system may be inoperable and may need to be reset.

Reset circuitry providing independent reset signal for trace and debug logic

An apparatus includes a main core processor configured to receive a first signal through a first main buffer, a second signal through a second main buffer, a third signal through a third main buffer, and a fourth signal through a fourth main buffer, a shadow core processor configured to receive the first signal through a first shadow buffer, the second signal through a second shadow buffer, the third signal through a third shadow buffer and the fourth signal through a fourth shadow buffer, and a first glitch suppression buffer coupled to a common node of an input of the first main buffer and an input of the first shadow buffer.

Glitch suppression apparatus and method

A system includes a write-data register and a read-data register, each clocked by a clock signal, and a first-in-first-out (FIFO) buffer coupled between the write-data register and the read-data register, the FIFO buffer including latches configured to store data. The system further includes glue logic with first, second, and third logic circuits configured to generate an internal write enable signal, an internal read valid signal, and an internal read enable signal based on an operational mode of the system. The system is configured to be selectively switched between a normal operational mode, where the latches are accessed for reading and writing by a read enable signal and write enable signal based on a read address signal and a write address signal, and a transition testing mode, where the latches are tested using the internal write enable signal, the internal read enable signal, and the internal read valid signal.

ATPG testing method for latch based memories, for area reduction

A system on a chip including a first-port controller for a first development port configured to receive a first development tool and a second-port controller for a second development port configured to receive a second development tool. The system on a chip further including a central controller in communication with the first-port controller, the second-port controller, and a security subsystem. The central controller being configured to manage authentication exchanges between the security subsystem and the first development tool and authentication exchanges between the security subsystem and the second development tool.

Central controller for multiple development ports

Disclosed herein is a method of operating a system in a test mode. When the test mode is an ATPG test mode, the method includes beginning stuck-at testing by setting a scan control signal to a logic one, setting a transition mode signal to a logic 0, and initializing FIFO buffer for ATPG test mode. The FIFO buffer is initialized for ATPG test mode by setting a scan reset signal to a logic 0 to place a write data register and a read data register associated with the FIFO buffer into a reset state, enabling latches of the FIFO buffer using an external enable signal, removing the external enable signal to cause the latches to latch, and setting the scan reset signal to a logic 1 to release the write data register and the read data register from the reset state, while not clocking the write data register.

A trace-data preparation circuit including a filtering circuit to receive traced memory-write data and a First In First Out buffer coupled with the filtering circuit to receive selected memory-write data filtered by the filtering circuit. The trace-data preparation circuit further including a data compression circuit to provide packaging data to a packaging circuit that groups the selected memory-write data.

Systems and methods for preparing trace data

A processing system includes: main and shadow processing cores configured to operate in lockstep based on a core clock. The main processing core includes a main processing core and a main debug circuit. The shadow processing core includes a shadow functional core and a shadow debug circuit. A redundancy checker circuit is configured to assert an alarm signal when a discrepancy between outputs from the main and shadow functional cores is detected. A debug bus synchronizer circuit is configured to receive input debug data in synchrony with a debug clock, and provide synchronized debug data in synchrony with the core clock to a debug bus based on the input debug data, where the main and shadow debug circuits are configured to receive the synchronized debug data in synchrony with the core clock from the debug bus, and where the debug clock is asynchronous with respect to the core clock.

Debug and trace circuit in lockstep architectures, associated method, processing system, and apparatus

An apparatus includes a main core processor configured to receive a first signal through a first main buffer, a second signal through a second main buffer, a third signal through a third main buffer and a fourth signal through a fourth main buffer, a shadow core processor configured to receive the first signal through a first shadow buffer, the second signal through a second shadow buffer, the third signal through a third shadow buffer and the fourth signal through a fourth shadow buffer, and a first glitch suppression buffer coupled to a common node of an input of the first main buffer and an input of the first shadow buffer.

Disclosed herein is logic circuitry and techniques for operation that hardware to enable the construction of first-in-first-out (FIFO) buffers from latches while permitting stuck-at-1 fault testing for the enable pin of those latches, as well as testing the data path at individual points through the FIFO buffer.

A testing tool includes a clock generation circuit generating a test clock and outputting the test clock via a test clock output pad, data processing circuitry clocked by the test clock, and data output circuitry receiving data output from the data processing circuitry and outputting the data via an input/output (IO) pad, the data output circuitry being clocked by the test clock. The testing tool also includes a programmable delay circuit generating a delayed version of the test clock, and data input circuitry receiving data input via the IO pad, the data input circuitry clocked by the delayed version of the test clock. The delayed version of the test clock is delayed to compensate for delay between transmission of a pulse of the test clock via the test clock output pad to an external computer and receipt of the data input from the external computer via the IO pad.

High speed debug-delay compensation in external tool

A synchronizer circuit includes a first synchronizer having a first input for receiving a signal associated with a first clock signal, a second input for receiving a second clock signal, and an output for providing a synchronizer circuit output signal; a second synchronizer having a first input for receiving the signal associated with the first clock signal, a second input for receiving the second clock signal, and an output; a detection stage having a first input coupled to the output of the first synchronizer and to the output of the second synchronizer, a second input for receiving the second clock signal, and an output; and a fault output stage having a first input coupled to the detection stage, a second input for receiving the second clock signal, and an output for providing a fault output signal.

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Greater Noida, India

Avneep Kumar Goyal