The disclosure describes a novel method and apparatus for improving the operation of a TAP architecture in a device through the use of Command signal inputs to the TAP architecture. In response to a Command signal input, the TAP architecture can perform streamlined and uninterrupted Update, Capture and Shift operation cycles to a target circuit in the device or streamlined and uninterrupted capture and shift operation cycles to a target circuit in the device. The Command signals can be input to the TAP architecture via the devices dedicated TMS or TDI inputs or via a separate CMD input to the device.

Circuits, systems, and methods are described herein for increasing a hold time of a master-slave flip-flop. A flip-flop includes circuitry configured to receive a scan input signal and generate a delayed scan input signal; a master latch configured to receive a data signal and the delayed scan input signal; and a slave latch coupled to the master latch, the master latch selectively providing one of the data signal or the delayed scan input signal to the slave latch based on a scan enable signal received by the master latch.

Circuits, systems, and methods are described herein for increasing a hold time of a master-slave flip-flop. A flip-flop includes circuitry configured to receive a scan input signal and generate a delayed scan input signal; a master latch configured to receive a data signal and the delayed scan input signal; and a slave latch coupled to the master latch, the master latch selectively providing one of the data signal or the delayed scan input signal to the slave latch based on a scan enable signal received by the master latch.

Techniques and mechanisms to exchange test, debug or trace (TDT) information via a general purpose input/output (I/O) interface. In an embodiment, an I/O interface of a device is coupled to an external TDT unit, wherein the I/O interface is compatible with an interconnect standard that supports communication of data other than any test information, debug information or trace information. One or more circuit components reside on the device or are otherwise coupled to the external TDT unit via the I/O interface. Information exchanged via the I/O interface is generated by, or results in, the performance of one or more TDT operations to evaluate the one or more circuit components. In another embodiment, the glue logic of the device interfaces the I/O interface with a test access point that is coupled between the one or more circuit components and the I/O interface.

Techniques and mechanisms to exchange test, debug or trace (TDT) information via a general purpose input/output (I/O) interface. In an embodiment, an I/O interface of a device is coupled to an external TDT unit, wherein the I/O interface is compatible with an interconnect standard that supports communication of data other than any test information, debug information or trace information. One or more circuit components reside on the device or are otherwise coupled to the external TDT unit via the I/O interface. Information exchanged via the I/O interface is generated by, or results in, the performance of one or more TDT operations to evaluate the one or more circuit components. In another embodiment, the glue logic of the device interfaces the I/O interface with a test access point that is coupled between the one or more circuit components and the I/O interface.

Technology is disclosed herein for testing circuitry that controls memory operations in a memory structure having non-volatile memory cells. The testing of the circuitry can be performed without the memory structure. The memory structure may reside on one semiconductor die, with sense blocks and a control circuit on another semiconductor die. The control circuit is able to perform die level control of memory operations in the memory structure. The control circuit may control the sense blocks to simulate sensing of non-volatile memory cells in the memory structure even though the sense blocks are not connected to the memory structure. The control circuit verifies correct operation of the semiconductor die based on the simulated sensing. For example, the control circuit may verify correct operation of a state machine that controls sense operations at a die level. Thus, the operation of the semiconductor die may be tested without the memory structure.

The present disclosure describes using the JTAG Tap's TMS and/or TCK terminals as general purpose serial Input/Output (I/O) Manchester coded communication terminals. The Tap's TMS and/or TCK terminal can be used as a serial I/O communication channel between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC. The use of the TMS and/or TCK terminal as serial I/O channels, as described, does not effect the standardized operation of the JTAG Tap, since the TMS and/or TCK I/O operations occur while the Tap is placed in a non-active steady state.

The present disclosure describes using the JTAG Tap's TMS and/or TCK terminals as general purpose serial Input/Output (I/O) Manchester coded communication terminals. The Tap's TMS and/or TCK terminal can be used as a serial I/O communication channel between; (1) an IC and an external controller, (2) between a first and second IC, or (3) between a first and second core circuit within an IC. The use of the TMS and/or TCK terminal as serial I/O channels, as described, does not effect the standardized operation of the JTAG Tap, since the TMS and/or TCK I/O operations occur while the Tap is placed in a non-active steady state.

In one embodiment, a device comprises: a first die having disposed thereon a first plurality of latches wherein ones of the first plurality of latches are operatively connected to an adjacent one of the first plurality of latches; and a second die having disposed thereon a second plurality of latches wherein ones of the second plurality of latches are operatively connected to an adjacent one of the second plurality of latches. Each latch of the first plurality of latches on said first die corresponds to a latch in the second plurality of latches on said second die. Each set of corresponding latches are operatively connected. A scan path comprises a closed loop comprising each of said first and second plurality of latches. One of the second plurality of latches is operatively connected to another one of the second plurality of latches via an inverter.

In one embodiment, a device comprises: a first die having disposed thereon a first plurality of latches wherein ones of the first plurality of latches are operatively connected to an adjacent one of the first plurality of latches; and a second die having disposed thereon a second plurality of latches wherein ones of the second plurality of latches are operatively connected to an adjacent one of the second plurality of latches. Each latch of the first plurality of latches on said first die corresponds to a latch in the second plurality of latches on said second die. Each set of corresponding latches are operatively connected. A scan path comprises a closed loop comprising each of said first and second plurality of latches. One of the second plurality of latches is operatively connected to another one of the second plurality of latches via an inverter.