| 摘要 |
PURPOSE: To provide a data transfer controller and electronic equipment, capable of simplifying circuit control or circuit configuration and improving effective bus transfer speed. CONSTITUTION: In a data transfer controller which user a USB (first bus), it is decided that a data phase (data transport and all data transfer) has ended on the condition that data transmission(DMA transfer) via an EBUS (second bus) is ended in an OUT transaction; and it is decided that the data phase has ended on the condition that data reception through the EBUS is ended, and that an 'Empty' signal is turned to be active, and the data storage area of a buffer is turned to be empty in an 'IN' transaction. The EBUS side is provided with a counter for counting the data size. When the data reception via the EBUS is ended, and the residual data size of the data storage area is less than the maximum packet size, the short packet of the data storage area is automatically transmitted via the USB, and the presence of the short packet is announced to firmware by using interrupt.
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