Printhead assembly priming

An inkjet printer, comprising:

• a printhead assembly including:
• a printhead;
• a fluid delivery passage through which ink may move to the printhead;
• an ink port through which ink may move between a removable ink container and the fluid delivery passage when the container is installed in the printer and connected to the printhead assembly;
• and
• an air port through which air may flow to and from the container when the container is installed in the printer and connected to the printhead assembly;
• a pressure source operatively connected to the air port;
• a vent operatively connected to the air port;
• and
• a controller operatively connected to the pressure source and to the vent, the controller configured to, when the container is installed in the printer and connected to the printhead assembly, cycle the source and the vent to alternately pressurize the container and then vent the container under conditions sufficient to push ink from the container through the ink port into the fluid delivery passage when the container is pressurized and then draw froth from the fluid delivery passage through the ink port into the container when the container is vented.

An inkjet printer, comprising:

• a printhead assembly including:
• a printhead;
• a fluid delivery passage through which ink may move to the printhead;
• an ink port through which ink may move between a removable ink container and the fluid delivery passage when the container is installed in the printer and connected to the printhead assembly;
• and
• an air port through which air may flow to and from the container when the container is connected to the printhead assembly;
• a pressure source operatively connected to the air port to pressurize the container to push ink from the container through the ink port into the printhead assembly;
• and
• a vent operatively connected to the air port to vent the pressurized container to generate a pressure difference of at least 25 inches of water across the ink port between the container and the printhead assembly.