Data recirculation in configured scan paths

A method comprising:

• (a) receiving a bit value at an automated test equipment (ATE) system from a first terminal;
• (b) sending a control signal to a second terminal from the ATE system based on determining from a Procedure Description Language (PDL) command of a set of PDL commands whether a bit value of a configured scan path is to be replaced with the replacement bit value, wherein the control signal causes one of the bit value and a replacement bit value to be selected;
• and
• (c) transitioning a clock signal on a third terminal such that the selected one of the bit value and the replacement bit value is shifted into the configured scan path on a bit-by-bit basis based on interpreting the set of PDL commands, wherein the configured scan path is shifted thereby causing the configured scan path to receive the bit value supplied in (b) and thereby causing the configured scan path to output a new bit value onto the first terminal, and repeating (a) through (c), and wherein the set of PDL commands indicates selection of the replacement bit value for at least one scan path location of the configured scan path and selection of at least one bit value for at least one other scan path location of the configured scan path.

A method comprising:

• (a) shifting out a bit value to an automated test equipment system (ATE) from a configured scan path via a TDO (Test Data Out) terminal and sending a control signal to an input terminal from the ATE system based on determining from a procedure Description Language (PDL) command of a set of PDL commands whether a bit value of the configured scan path is to be replaced with the replacement bit value, such that in response to the control signal either the shifted out bit value is shifted back into the configured scan path or a replacement bit value is substituted for the shifted out bit value and the replacement bit value is shifted into the configured scan path via a TDI (Test Data In) terminal, wherein the configured scan path includes a plurality of bits, and wherein prior to (a) each bit of the configured scan path stored a corresponding bit value;
• and
• (b) repeating (a) on a bit-by-bit basis for each successive bit value stored in the configured scan path based on interpreting the set of PDL commands, such that after all the bit values previously stored in the configured scan path have been shifted out via the TDO terminal each bit of the configured scan path was either reloaded to store its prior shifted out bit value or was loaded to store the replacement bit value, and wherein the set of PDL commands indicates selection of the replacement bit value for at least one scan path location of the configured scan path and selection of at least one bit value for at least one other scan path location of the configured scan path.

An Automated Test Equipment (ATE) system comprising:

• a storage medium storing a set of Procedure Description Language (PDL) commands;
• a first terminal configured to couple to a Test Data Out (TDO) terminal of a Device Under Test (DUT);
• a second terminal configured to couple to a Test Data In (TDI) terminal of the DUT;
• a third terminal configured to couple to a Test Clock (TCK) terminal of the DUT;
• a fourth terminal configured to couple to an input terminal of the DUT;
• and
• a command interpreting mechanism configured to interpret the set of PDL commands and as a result of the interpreting uses the first, second, third and fourth terminals thereby causing:
• (a) shifting out a bit value from a configured scan path of the DUT via the TDO terminal of the DUT and sending a control signal to the input terminal of the DUT based on determining from a PDL command of the set of PDL commands whether a bit value of the configured scan path is to be replaced with the replacement bit value, such that either the shifted out bit value is shifted back into the configured scan path or a replacement bit value is substituted for the shifted out bit value and the replacement bit value is shifted into the configured scan path via the TDI terminal of the DUT, wherein the configured scan path includes a plurality of bits, and wherein prior to (a) each bit of the configured scan path stored a corresponding bit value;
• and
• (b) repeating (a) on a bit-by-bit basis based on interpreting the set of PDL commands for each successive bit value stored in the configured scan path such that after all the bit values previously stored in the configured scan path have been shifted out via the TDO terminal each bit of the configured scan path was either reloaded to store its prior shifted out bit value or was loaded to store the replacement bit value, and wherein the set of PDL commands indicates selection of the replacement bit value for at least one scan path location of the configured scan path and selection of at least one bit value for at least one other scan path location of the configured scan path.

An Automated Test Equipment (ATE) apparatus comprising:

• a storage medium configured to store a set of Procedure Description Language (PDL) commands;
• and
• means for interpreting the PDL commands and as a result of the interpreting:
• (a) causing a bit value to be received from a TDO (Test Data Out) terminal of a Device Under Test (DUT);
• (b) causing a replacement bit value to be supplied to a TDI (Test Data In) terminal of the DUT;
• (c) causing a control signal to be sent to an input terminal of the DUT from the ATE system based on determining from a PDL command of the set of PDL commands whether a bit value of a configured scan path is to be replaced with the replacement bit value, wherein the control signal causes one of the bit value and the replacement bit value to be selected;
• (d) causing the selected one of the bit value and the replacement bit value to be shifted into the configured scan path of the DUT, thereby shifting the configured scan path and outputting a new bit value onto the TDO terminal, and repeating (a) through (d) on a bit-by-bit basis based on interpreting the set of PDL commands, and wherein the set of PDL commands indicates selection of the replacement bit value for at least one scan path location of the configured scan path and selection of at least one bit value for at least one other scan path location of the configured scan path.

A computer product, comprising:

• a non-transitory computer-readable medium storing codes executable to cause an apparatus to:
• (a) shift out a bit value from a configured scan path via a TDO (Test Data Out) terminal to an Automated Test Equipment (ATE) system and send a control signal from the ATE system to an input terminal based on determining from a Procedure Description Language (PDL) command of a set of PDL commands whether a bit value of a configured scan path is to be replaced with the replacement bit value, such that either the shifted out bit value is shifted back into the configured scan path or a replacement bit value is substituted for the shifted out bit value and the replacement bit value is shifted into the configured scan path via a TDI (Test Data In) terminal, wherein the configured scan path includes a plurality of bits, and wherein prior to (a) each bit of the configured scan path stored a corresponding bit value;
• and wherein the code is also executable to cause an apparatus to
• (b) repeat (a) on a bit-by-bit basis based on interpreting the set of PDL commands for each successive bit value stored in the configured scan path such that after all the bit values previously stored in the configured scan path have been shifted out via the TDO terminal each bit of the configured scan path was either reloaded to store its prior shifted out bit value or was loaded to store the replacement bit value, and wherein the set of PDL commands indicates selection of the replacement bit value for at least one scan path location of the configured scan path and selection of at least one bit value for at least one other scan path location of the configured scan path.