Evaluating print head nozzle condition

A print die comprising:

• a plurality of nozzle columns on the print die, wherein each of the plurality of nozzle columns comprises a respective set of nozzles;
• a first time repository on the print die to store a first time instant, and a second time repository on the print die to store a second time instant;
• a plurality of drive bubble detect modules provided onto the print die, wherein each of the plurality of drive bubble detect modules is coupled to each of the set of nozzles of a corresponding nozzle column from among the plurality of nozzle columns, wherein each of the drive bubble detect modules is to:
• register, for a nozzle of the corresponding set of nozzles at the first time instant obtained from the first time repository, a first test result obtained based on an impedance measured across the nozzle;
• register, for the nozzle at the second time instant obtained from the second time repository, a second test result obtained based on an impedance measured across the nozzle;
• and
• determine a nozzle condition of the nozzle based on the first test result and the second test result;
• and
• a timing circuit on the print die and coupled to each of the plurality of drive bubble detect modules, wherein the timing circuit is to activate the plurality of drive bubble detect modules at the first time instant and the second time instant, to register the first test result and the second test result.

A print die comprising:

• a plurality of nozzle columns on the print die, wherein each of the plurality of nozzle columns comprises a set of nozzles;
• a plurality of drive bubble detect modules on the print die, wherein each of the plurality of drive bubble detect modules is coupled to the set of nozzles of a corresponding nozzle column from among the plurality of nozzle columns, wherein each of the plurality of drive bubble detect modules is to:
• register, for a nozzle from among the set of nozzles of the corresponding nozzle column, a first test result in a first memory element on the print die, based on comparing a first measure of impedance associated with the nozzle at a first predetermined time instant;
• register a second test result in a second memory element on the print die, based on comparing a second measure of impedance associated with the nozzle at a second time instant;
• and
• determine a condition of the nozzle based on the first test result and the second test result;
• and
• a timing circuit on the print die and coupled to each of the plurality of drive bubble detect modules, wherein the timing circuit is to activate the plurality of drive bubble detect modules, at the first predetermined time instant and the second predetermined time instant, to register the first test result and the second test result.