An apparatus includes a core logic circuit, one or more integrated clock-gating (ICG) cells, and one or more ICG control cells (ICCs). The core logic circuit generally comprises a plurality of flip-flops. The plurality of flip-flops may be connected to form one or more scan chains. Each of the one or more integrated clock-gating (ICG) cells may be configured to gate a clock signal of a respective one of the one or more scan chains. Each of the one or more ICG control cells may be configured to control a respective one or more of the one or more ICG cells.

An apparatus includes a core logic circuit, one or more integrated clock-gating (ICG) cells, and one or more ICG control cells (ICCs). The core logic circuit generally comprises a plurality of flip-flops. The plurality of flip-flops may be connected to form one or more scan chains. Each of the one or more integrated clock-gating (ICG) cells may be configured to gate a clock signal of a respective one of the one or more scan chains. Each of the one or more ICG control cells may be configured to control a respective one or more of the one or more ICG cells.

Scan channel slicing methods and systems for testing of scan chains in an integrated circuit (IC) reduce the number of test cycles needed to effectively test all the scan chains in the IC, reducing the time and cost of testing. In scan channel slicing, rather than loading and unloading into scan chains high-power patterns having numerous switching transitions over the length of each scan chain, loading and unloading the entirety of the scan chain scan while observing it, chain load data is sliced, apportioning between the different scan chains independently observable sections (slices) of transition data in which all four bit-to-bit transitions (“0” to “0”, “0” to “1”, “1” to 0”, “1” to “1”) are ensured to exist. The remainder of the scan chain load data, which is not observed in the test procedure, can be low-transition data that consumes low dynamic power, such as mostly zeroes or mostly ones.

Scan channel slicing methods and systems for testing of scan chains in an integrated circuit (IC) reduce the number of test cycles needed to effectively test all the scan chains in the IC, reducing the time and cost of testing. In scan channel slicing, rather than loading and unloading into scan chains high-power patterns having numerous switching transitions over the length of each scan chain, loading and unloading the entirety of the scan chain scan while observing it, chain load data is sliced, apportioning between the different scan chains independently observable sections (slices) of transition data in which all four bit-to-bit transitions (“0” to “0”, “0” to “1”, “1” to 0”, “1” to “1”) are ensured to exist. The remainder of the scan chain load data, which is not observed in the test procedure, can be low-transition data that consumes low dynamic power, such as mostly zeroes or mostly ones.

Electronic scan circuitry includes a decompressor (510), a plurality of scan chains (520.i) fed by the decompressor (510), a scan circuit (502, 504) coupled to the plurality of scan chains (520.i) to scan them in and out, a masking circuit (590) fed by the scan chains (520.i), and a scannable masking qualification circuit (550, 560, 580) coupled to the masking circuit (590), the masking qualification circuit (550, 560, 580) scannable by scan-in of bits by the decompressor (510) along with scan-in of the scan chains (520.i), and the scannable masking qualification circuit (550, 560, 580) operable to hold such scanned-in bits upon scan-out of the scan chains through the masking circuit (590). Other scan circuitry, processes, circuits, devices and systems are also disclosed.

Electronic scan circuitry includes a decompressor (510), a plurality of scan chains (520.i) fed by the decompressor (510), a scan circuit (502, 504) coupled to the plurality of scan chains (520.i) to scan them in and out, a masking circuit (590) fed by the scan chains (520.i), and a scannable masking qualification circuit (550, 560, 580) coupled to the masking circuit (590), the masking qualification circuit (550, 560, 580) scannable by scan-in of bits by the decompressor (510) along with scan-in of the scan chains (520.i), and the scannable masking qualification circuit (550, 560, 580) operable to hold such scanned-in bits upon scan-out of the scan chains through the masking circuit (590). Other scan circuitry, processes, circuits, devices and systems are also disclosed.

Topology discovery of a target system having a plurality of components coupled with a scan topology may be performed by driving a low logic value on the data input signal and a data output signal of the scan topology. An input data value and an output data value for each of the plurality of components is sampled and recorded. A low logic value is then scanned through the scan path and recorded at each component. The scan topology may be determined based on the recorded data values and the recorded scan values.

Topology discovery of a target system having a plurality of components coupled with a scan topology may be performed by driving a low logic value on the data input signal and a data output signal of the scan topology. An input data value and an output data value for each of the plurality of components is sampled and recorded. A low logic value is then scanned through the scan path and recorded at each component. The scan topology may be determined based on the recorded data values and the recorded scan values.

Existing multi-wire debugging protocols, such as 4-wire JTAG, 2-wire cJTAG, or ARM SWD, are run through a serial wireless link by providing the debugger and the target device with hardware interfaces that include UARTs and conversion bridges. The debugger interface serializes outgoing control signals and de-serializes returning data. The target interface de-serializes incoming control signals and serializes outgoing data. The actions of the interfaces are transparent to the inner workings of the devices, allowing re-use of existing debugging software. Compression, signal combining, and other optional enhancements increase debugging speed and flexibility while wirelessly accessing target devices that may be too small, too difficult to reach, or too seal-dependent for a wired connection.

Existing multi-wire debugging protocols, such as 4-wire JTAG, 2-wire cJTAG, or ARM SWD, are run through a serial wireless link by providing the debugger and the target device with hardware interfaces that include UARTs and conversion bridges. The debugger interface serializes outgoing control signals and de-serializes returning data. The target interface de-serializes incoming control signals and serializes outgoing data. The actions of the interfaces are transparent to the inner workings of the devices, allowing re-use of existing debugging software. Compression, signal combining, and other optional enhancements increase debugging speed and flexibility while wirelessly accessing target devices that may be too small, too difficult to reach, or too seal-dependent for a wired connection.