摘要:
The present invention is directed to a universal serial bus (USB) transaction translator and an associated IN/OUT bulk transaction method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus, wherein the host USB version is higher than the device USB version. At least two buffers configured to store data are disposed between the device interface and the host interface. A controller stores the data in the buffers alternately. In a bulk-IN transaction, before the host sends an IN packet, the controller pre-fetches data and stores the data in the buffers until all the buffers are full or a requested data length has been achieved; the pre-fetched data are then sent to the host after the host sends the IN packet. In a bulk-OUT transaction, the controller stores the data sent from the host in the buffers, and the data are then post-written to the device.
摘要:
A data transmission system is provided. The data transmission system includes a first control circuit coupled to a first device, a translation circuit coupled to the first control circuit and a second control circuit coupled to the translation circuit. The first control circuit decodes a first format data packet sent by the first device. The translation circuit receives the decoded first format data packet and translates the decoded first format data packet into a second format data packet. The second control circuit transmits the second format data packet to a host. A data transmission rate of the first device is slower than that of a second device, and the data transmission system is backward compatible to the first device.
摘要:
A data transmission system is provided. The data transmission system includes a first control circuit coupled to a first device, a translation circuit coupled to the first control circuit and a second control circuit coupled to the translation circuit. The first control circuit decodes a first format data packet sent by the first device. The translation circuit receives the decoded first format data packet and translates the decoded first format data packet into a second format data packet. The second control circuit transmits the second format data packet to a host. A data transmission rate of the first device is slower than that of a second device, and the data transmission system is backward compatible to the first device.
摘要:
The present invention is directed to a universal serial bus (USB) transaction translator and a micro-frame synchronization method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus, wherein the host USB version is higher than the device USB version. At least two buffers configured to store data are disposed between the device interface and the host interface. A controller stores the data in the buffers alternately. A start-of-frame (SOF) counter is used to count the SOF packets, wherein the counting value of the SOF counter is compared to a predefined value. Specifically, the controller resets a SOF timer for sending the SOF packet when the counting value achieves the predefined value or is greater than the predefined value, such that the SOF packet and an isochronous timestamp packet (ITP) from the host are sent at the same time. Further, the controller delays the sending of the SOF packet for a period of time according to the ITP from the host.
摘要:
The present invention is directed to a universal serial bus (USB) transaction translator and an associated IN isochronous transaction method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus, wherein the host USB version is higher than the device USB version. At least two buffers configured to store data are disposed between the device interface and the host interface. A controller stores the data in the buffers alternately. A register is used to record device bus information. Before the host sends an IN packet, the controller pre-fetches data from the device according to the device bus information and then stores the data in the buffers; the controller responds with the pre-fetched data to the host after the host sends the IN packet.
摘要:
The present invention is directed to a universal serial bus (USB) transaction translator and an associated IN/OUT bulk transaction method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus, wherein the host USB version is higher than the device USB version. At least two buffers configured to store data are disposed between the device interface and the host interface. A controller stores the data in the buffers alternately. In a bulk-IN transaction, before the host sends an IN packet, the controller pre-fetches data and stores the data in the buffers until all the buffers are full or a requested data length has been achieved; the pre-fetched data are then sent to the host after the host sends the IN packet. In a bulk-OUT transaction, the controller stores the data sent from the host in the buffers, and the data are then post-written to the device.
摘要:
The present invention is directed to a universal serial bus (USB) transaction translator and a micro-frame synchronization method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus, wherein the host USB version is higher than the device USB version. At least two buffers configured to store data are disposed between the device interface and the host interface. A controller stores the data in the buffers alternately. A start-of-frame (SOF) counter is used to count the SOF packets, wherein the counting value of the SOF counter is compared to a predefined value. Specifically, the controller resets a SOF timer for sending the SOF packet when the counting value achieves the predefined value or is greater than the predefined value, such that the SOF packet and an isochronous timestamp packet (ITP) from the host are sent at the same time. Further, the controller delays the sending of the SOF packet for a period of time according to the ITP from the host. In another embodiment, the sending period of SOF packets may be dynamically adjusted in isochronous transfer.
摘要:
The present invention is directed to a universal serial bus (USB) transaction translator and an associated IN isochronous transaction method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus, wherein the host USB version is higher than the device USB version. At least two buffers configured to store data are disposed between the device interface and the host interface. A controller stores the data in the buffers alternately. A register is used to record device bus information. Before the host sends an IN packet, the controller pre-fetches data from the device according to the device bus information and then stores the data in the buffers; the controller responds with the pre-fetched data to the host after the host sends the IN packet.
摘要:
The present invention is directed to a universal serial bus (USB) transaction translator and a micro-frame synchronization method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus, wherein the host USB version is higher than the device USB version. At least two buffers configured to store data are disposed between the device interface and the host interface. A controller stores the data in the buffers alternately. A start-of-frame (SOF) counter is used to count the SOF packets, wherein the counting value of the SOF counter is compared to a predefined value. Specifically, the controller resets a SOF timer for sending the SOF packet when the counting value achieves the predefined value or is greater than the predefined value, such that the SOF packet and an isochronous timestamp packet (ITP) from the host are sent at the same time. Further, the controller delays the sending of the SOF packet for a period of time according to the ITP from the host. In another embodiment, the sending period of SOF packets may be dynamically adjusted in isochronous transfer.
摘要:
The present invention is directed to a universal serial bus (USB) transaction translator and a micro-frame synchronization method. A device interface is coupled to a device via a device bus, and a host interface is coupled to a host via a host bus, wherein the host USB version is higher than the device USB version. At least two buffers configured to store data are disposed between the device interface and the host interface. A controller stores the data in the buffers alternately. A start-of-frame (SOF) counter is used to count the SOF packets, wherein the counting value of the SOF counter is compared to a predefined value. Specifically, the controller resets a SOF timer for sending the SOF packet when the counting value achieves the predefined value or is greater than the predefined value, such that the SOF packet and an isochronous timestamp packet (ITP) from the host are sent at the same time. Further, the controller delays the sending of the SOF packet for a period of time according to the ITP from the host.