Printing apparatus, printing method, and computer-readable storage medium

A method to be implemented in a printing apparatus, the printing apparatus comprising a main controlling circuit;

• a subsidiary controlling circuit group including a plurality of subsidiary controlling circuits connected with one another serially, the subsidiary controlling circuit group being configured to transmit print data received from the main controlling circuit from upstream to downstream through the plurality of subsidiary controlling circuits, the plurality of subsidiary controlling circuits including a first subsidiary controlling circuit and a second subsidiary controlling circuit on an upstream side of the first subsidiary controlling circuit;
• and a plurality of heads, the method comprising:
• based on a volume of outgoing data to be transmitted from the first subsidiary controlling circuit to one of the plurality of heads corresponding to the first subsidiary controlling circuit and a volume of incoming data from the second subsidiary controlling circuit to be received by the first subsidiary controlling circuit, determining whether a first data-transfer request is to be transmitted from the first subsidiary controlling circuit to the second subsidiary controlling circuit, the first data-transfer request being a request for the print data to be transferred from upstream to the first subsidiary controlling circuit;
• and
• based on a determination that the first data-transfer request is to be transmitted, transmitting the first data-transfer request from the first subsidiary controlling circuit to the second subsidiary controlling circuit.

A non-transitory computer readable storage medium storing computer readable instructions that are executable by a computer in a printing apparatus, the printing apparatus comprising a main controlling circuit;

• a subsidiary controlling circuit group including a plurality of subsidiary controlling circuits connected with one another serially, the subsidiary controlling circuit group being configured to transmit print data received from the main controlling circuit from upstream to downstream through the plurality of subsidiary controlling circuits, the plurality of subsidiary controlling circuits including a first subsidiary controlling circuit and a second subsidiary controlling circuit on an upstream side of the first subsidiary controlling circuit;
• and a plurality of heads, the computer readable instructions, when executed by the computer, causing the computer to:
• based on a volume of outgoing data to be transmitted from the first subsidiary controlling circuit to one of the plurality of heads and a volume of incoming data from the second subsidiary controlling circuit to be received by the first subsidiary controlling circuit, determine whether a first data-transfer request is to be transmitted from the first subsidiary controlling circuit to the second subsidiary controlling circuit, the first data-transfer request being a request for the print data to be transferred from upstream to the first subsidiary controlling circuit;
• and
• based on a determination that the first data-transfer request is to be transmitted, transmit the first data-transfer request from the first subsidiary controlling circuit to the second subsidiary controlling circuit.