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US 7,461,318 B2Granted
Communication system realizing USB communications between a host computer and its peripheral device and a communication controller transmitting a USB signal under the USB standard
AssigneeSharp Kabushiki Kaisha
InventorsFumihiro Fukae, Hitoshi Naoe, Koji Sakai, Shohei Osawa
Life of this patent
Estimating the term…
Abstract
A two-way transmission system of the present invention is arranged in such a manner that, when a host-side controller confirms the receipt of an IN packet from a USB host, the host-side controller transfers the IN packet to a function-side controller, and receives a DATA packet from the function side. The received DATA packet is temporarily stored in a FIFO. At the time of the receipt of the IN packet again, the host-side controller supplies, to the USB host, the DATA packet stored in the FIFO.
Claims95
A communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a host-side controller that (i) transfers an IN packet, which is supplied from a host device, to a function device side, while (ii) transfers a DATA packet, which is a response to the IN packet, to the host device,
- the communication controller comprising:
- receipt acknowledgement means for acknowledging receipt of the IN packet from the host device;
- storage means for storing the DATA packet supplied from the function device side;
- wherein when another IN packet is supplied from the host device side before receiving from the host side device an ACK packet in response to the DATA packet transmitted to the host device side, the communication controller holding said another IN packet,
- data storage acknowledgement means for checking if the DATA packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of said another IN packet from the host device;
- and
- transmission control means for (I) transmitting, to the function device side, said another IN packet which is supplied from the host device, and transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is not stored, and for (II) transmitting the DATA packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is stored.
4 more elements
A communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a function-side controller that (i) transfers a USB-compliant IN packet, which is supplied from a host device, to a function device side, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device side,
- when the IN packet is supplied from the host device side, the communication controller holding this IN packet,
- wherein when another IN packet is supplied from the host device side before receiving from the host side device an ACK packet in response to the DATA packet transmitted to the host device side, the communication controller holding said another IN packet, and
- when an ACK packet is supplied from the host device side in response to the DATA packet transmitted to the host device side, the communication controller supplying said another IN packet, which has been held, to a USB function, and supplying the ACK packet to the function device when the DATA packet is supplied from the function device, in response to said another IN packet.
A communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a function-side controller that (i) transfers a USB-compliant IN packet, which is supplied from a host device, to a function device side, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device side,
- if a retransmission request is supplied from a host-side controller, the communication controller carrying out a retransmission process so as to transmit, to the host-side controller, a DATA packet identical with the DATA packet transmitted to the host-side controller on a last occasion.
A communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a function-side controller that (i) transfers an IN packet, which is supplied from a host device side, to a function device, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device side,
- when a retransmission request is supplied from the host-side controller, the communication controller supplying (I) the IN packet to the function device and (II) the DATA packet, which is supplied in response to the IN packet, to the host-side controller.
A communication system, comprising:
- a communication controller acting as a host-side controller;
- and
- a communication controller acting as a function-side controller,
- the communication controller acting as the host-side controller that, when an IN transaction is performed as data communication under USB standard, (i) transfers a USB-compliant IN packet, which is supplied from a host device, to a function device side, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device side,
- the communication controller acting as the host-side controller including:
- receipt acknowledgement means for acknowledging receipt of the IN packet from the host device;
- storage means for storing the DATA packet supplied from a function device side;
- wherein when another IN packet is supplied from the host device side before receiving from the host side device an ACK packet in response to the DATA packet transmitted to the host device side, the communication controller holding said another IN packet,
- data storage acknowledgement means for checking if the DATA packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of said another IN packet from the host device;
- and
- transmission control means for (I) transmitting, to the function device side, said another IN packet which is supplied from the host device, and transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is not stored, and for (II) transmitting the DATA packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is stored,
- the communication controller acting as the function-side controller (1) transferring the USB-compliant IN packet, which is supplied from the host device side, to the function device, while (2) transferring the DATA packet, which is a response to said another IN packet, to the host device side.
9 more elements
A communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a host-side controller that (i) transfers a USB-compliant IN packet, which is supplied from a host device, to a function device side, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device,
- the communication controller comprising:
- receipt acknowledgement means for acknowledging receipt of the IN packet from the host device;
- storage means for storing the DATA packet supplied from the function device side;
- wherein when another IN packet is supplied from the host device side before receiving from the host side device an ACK packet in response to the DATA packet transmitted to the host device side, the communication controller holding said another IN packet,
- data storage acknowledgement means for checking if the DATA packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of said another IN packet from the host device;
- and
- transmission control means for (I) transmitting, to the function device side, said another IN packet which is supplied from the host device, and transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is not stored, and for (II) transmitting the DATA packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is stored.
4 more elements
A communication equipment, comprising:
- a communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a function-side controller that (i) transfers a USB-compliant IN packet, which is supplied from a host device side, to a function device, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device side,
- when the IN packet is supplied from the host device side, the communication controller holding this IN packet,
- wherein when another IN packet is supplied from the host device side before receiving from the host side device an ACK packet in response to the DATA packet transmitted to the host device side, the communication controller holding said another IN packet, and
- when an ACK packet is supplied from the host device side in response to the DATA packet transmitted to the host device side, the communication controller supplying said another IN packet, which has been held, to a USB function, and supplying the ACK packet to the function device when the DATA packet is supplied from the function device, in response to said another IN packet.
1 more element
A communication equipment, comprising:
- a communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a function-side controller that (I) transfers a USB-compliant IN packet, which is supplied from a host device, to a function device, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device side,
- if a retransmission request is supplied from a host-side controller, the communication controller carrying out a retransmission process so as to transmit, to the host-side controller, a DATA packet identical with the DATA packet transmitted to the host-side controller on a last occasion.
A communication equipment, comprising:
- a communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a function-side controller that (i) transfers a USB-compliant IN packet, which is supplied from a host device, to a function device side, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device side,
- when a retransmission request is supplied from a host-side controller, the communication controller supplying (I) the IN packet to the function device and (II) the DATA packet, which is supplied in response to the IN packet, to the host-side controller.
A communication method, comprising the steps of:
- when receipt of an IN packet from a host device is confirmed, checking whether or not a DATA packet which will be a response to the IN packet has been supplied;
- when another IN packet is received from a host device side before receiving from the host side device an ACK packet in response to the DATA packet transmitted to the host device side, holding said another IN packet;
- if the DATA packet has been supplied, transmitting the DATA packet to the host device, in response to the received IN packet;
- if the DATA packet has not been supplied, transferring said another IN packet to a function device side, and transmitting a NAK packet to the host device, and
- if the DATA packet has not been supplied and said another IN packet has not been received, transferring the received IN packet to a function device side, and transmitting a NAK packet to the host device.
2 more elements
A packet-based communication program which causes a computer to perform as means of a communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a host-side controller that (i) transfers a USB-compliant IN packet, which is supplied from a host device, to a function device side, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device,
- the communication controller comprising:
- receipt acknowledgement means for acknowledging receipt of the IN packet from the host device;
- storage means for storing the DATA packet supplied from the function device side;
- wherein when another IN packet is received from a host device side before receiving from the host side device an ACK packet in response to the DATA packet transmitted to the host device side, holding said another IN packet,
- data storage acknowledgement means for checking if the DATA packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of said another IN packet from the host device;
- and
- transmission control means for (I) transmitting, to the function device side, said another IN packet which is supplied from the host device, and transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is not stored, and for (II) transmitting the DATA packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is stored.
4 more elements
A storage medium storing a packet-based communication program which causes a computer to perform as means of a communication controller which acts, when an IN transaction is performed as data communication under USB standard, as a host-side controller that (i) transfers an IN packet, which is supplied from a host device, to a function device side, while (ii) transfers a DATA packet, which is a response to the IN packet, to a host device,
- the communication controller comprising:
- receipt acknowledgement means for acknowledging receipt of the IN packet from the host device;
- storage means for storing the DATA packet supplied from the function device side;
- wherein when another IN packet is received from a host device side before receiving from the host side device an ACK packet in response to the DATA packet transmitted to the host device side, holding said another IN packet,
- data storage acknowledgement means for checking if the DATA packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of said another IN packet from the host device;
- and
- transmission control means for (I) transmitting, to the function device side, said another IN packet which is supplied from the host device, and transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is not stored, and for (II) transmitting the DATA packet to the host device, when the data storage acknowledgement means confirms that the DATA packet is stored.
4 more elements
A communication controller which acts, when an OUT transaction is performed as data communication under USB standard, as a host-side controller that (i) transfers an OUT packet and a DATA packet, which are supplied from a host device, to a function device side, while (ii) transfers a handshake packet, which is a response to the OUT packet and the DATA packet, to the host device,
- the communication controller comprising:
- receipt acknowledgement means for acknowledging receipt of the OUT packet and the DATA packet from the host device;
- storage means for storing the handshake packet supplied from the function device side;
- data storage acknowledgement means for checking if the handshake packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of the OUT packet and the DATA packet from the host device;
- and
- transmission control means for (I) transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is not stored, and for (II) transmitting the handshake packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is stored,
- wherein, the communication controller also acts as a function-side controller which (i) transfers USB-compliant OUT packet and DATA packet, which are supplied from a host device side, to a function device, and (ii) transfers the handshake packet, which is a response to the USB-compliant OUT packet and DATA packet, to the host device side,
- a transfer rate for receipt of the OUT packet and the DATA packet from a host-side controller and a transfer rate for transmission of the handshake packet to the host-side controller are lower than a transfer rate defined by USB standard, and a transfer rate for transmission of the OUT packet and the DATA packet to the function device and a transfer rate regarding receipt of the handshake packet from the function device are identical with the transfer rate defined by USB standard,
- data amount confirming means for confirming amounts of data of the OUT packet and the DATA packet at a time of storing the OUT packet and the DATA packet in the storage means is additionally provided, the OUT packet and the DATA packet being supplied from the host-side controller, and
- the transmission control means starts to transmit the OUT packet and the DATA packet to the function device, when the amounts of data confirmed by the data amount confirming means exceed a predetermined value.
7 more elements
A communication controller which acts, when an OUT transaction is performed as data communication under USB standard, as a function-side controller that (i) transfers an OUT packet and a DATA packet, which are supplied from a host device side, to a function device, while (ii) transfers a handshake packet, which is a response to the OUT packet and the DATA packet, to the host device side,
- a transfer rate regarding transmission to the host device side being lower than a transfer rate defined by USB standard, while a transfer rate regarding transmission to the function device being identical with the transfer rate defined by USB standard,
- the communication controller further comprising data amount confirming means for confirming amounts of data of the OUT packet and the DATA packet at a time of storing the OUT packet and the DATA packet in the storage means, the OUT packet and the DATA packet being supplied from the host-side controller, and
- the transmission control means starting to transmit the OUT packet and the DATA packet to the function device, when the amounts of data confirmed by the data amount confirming means exceed a predetermined value.
A communication system, comprising:
- a communication controller acting as a host-side controller;
- and
- a communication controller acting as a function-side controller,
- the communication controller acting as the host-side controller that, when an OUT transaction is performed as data communication under USB standard, (i) transfers an OUT packet and a DATA packet, which are supplied from a host device, to a function device side, while (ii) transfers a handshake packet, which is a response to the OUT packet and the DATA packet, to a host device,
- the communication controller acting as the host-side controller including:
- receipt acknowledgement means for acknowledging receipt of the OUT packet and the DATA packet from the host device;
- storage means for storing the handshake packet supplied from a function device side;
- data storage acknowledgement means for checking if the handshake packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of the OUT packet and the DATA packet from the host device;
- and
- transmission control means for (I) transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is not stored, and for (II) transmitting the handshake packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is stored,
- the communication controller acting as the function-side controller (1) transferring USB-compliant OUT packet and DATA packet, which are supplied from the host device side, to the function device, while (2) transferring the handshake packet, which is a response to the USB-compliant OUT packet and DATA packet, to the host device side,
- wherein, the communication controller also acts as a function-side controller which (i) transfers USB-compliant OUT packet and DATA packet, which are supplied from a host device side, to a function device, and (ii) transfers the handshake packet, which is a response to the USB-compliant OUT racket and DATA packet, to the host device side,
- a transfer rate for receipt of the OUT packet and the DATA packet from a host-side controller and a transfer rate for transmission of the handshake packet to the host-side controller are lower than a transfer rate defined by USB standard, and a transfer rate for transmission of the OUT packet and the DATA packet to the function device and a transfer rate regarding receipt of the handshake packet from the function device are identical with the transfer rate defined by USB standard,
- data amount confirming means for confirming amounts of data of the OUT packet and the DATA packet at a time of storing the OUT packet and the DATA packet in the storage means is additionally provided, the OUT packet and the DATA packet being supplied from the host-side controller, and
- the transmission control means starts to transmit the OUT packet and the DATA packet to the function device, when the amounts of data confirmed by the data amount confirming means exceed a predetermined value.
12 more elements
A communication equipment, comprising a communication controller which acts, when an OUT transaction is performed as data communication under USB standard, as a host-side controller that (i) transfers an OUT packet and a DATA packet, which are supplied from a host device, to a function device side, while (ii) transfers a handshake packet, which is a response to the OUT packet and the DATA packet, to the host device,
- the communication controller comprising:
- receipt acknowledgement means for acknowledging receipt of the OUT packet and the DATA packet from the host device;
- storage means for storing the handshake packet supplied from the function device side;
- data storage acknowledgement means for checking if the handshake packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of the OUT packet and the DATA packet from the host device;
- and
- transmission control means for (I) transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is not stored, and for (II) transmitting the handshake packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is stored,
- wherein, the communication controller also acts as a function-side controller which (i) transfers USB-compliant OUT packet and DATA packet, which are supplied from a host device side, to a function device, and (ii) transfers the handshake packet, which is a response to the USB-compliant OUT packet and DATA packet, to the host device side,
- a transfer rate for receipt of the OUT packet and the DATA packet from a host-side controller and a transfer rate for transmission of the handshake packet to the host-side controller are lower than a transfer rate defined by USB standard, and a transfer rate for transmission of the OUT packet and the DATA packet to the function device and a transfer rate regarding receipt of the handshake packet from the function device are identical with the transfer rate defined by USB standard,
- data amount confirming means for confirming amounts of data of the OUT packet and the DATA packet at a time of storing the OUT packet and the DATA packet in the storage means is additionally provided, the OUT packet and the DATA packet being supplied from the host-side controller, and
- the transmission control means starts to transmit the OUT packet and the DATA packet to the function device, when the amounts of data confirmed by the data amount confirming means exceed a predetermined value.
7 more elements
A communication equipment, comprising a communication controller which acts as a function-side controller which, at a time of performing an OUT transaction as a data communication under USB standard, (i) transfers USB-compliant OUT packet and DATA packet, which are supplied from a host device side, to a function device, and (ii) transfers a handshake packet, which is a response to the USB-compliant OUT packet and DATA packet, to the host device side,
- a transfer rate regarding transmission to the host device side being lower than a transfer rate defined by USB standard, while a transfer rate regarding transmission to the function device being identical with the transfer rate defined by USB standard,
- the communication controller including data amount confirming means for confirming amounts of data of the OUT packet and the DATA packet at a time of storing the OUT packet and the DATA packet in the storage means, the OUT packet and the DATA packet being supplied from the host-side controller, and
- the transmission control means starting to transmit the OUT packet and the DATA packet, when the amounts of data confirmed by the data amount confirming means exceed a predetermined value.
A communication method, comprising the steps of:
- when receipt of an OUT packet and a DATA packet from a host device is confirmed, checking whether or not a handshake packet which will be a response to the OUT packet and the DATA packet has been supplied;
- if the handshake packet has been supplied, transmitting the handshake packet to the host device, in response to the OUT packet and the DATA packet having been supplied;
- and
- if the handshake packet has not been supplied, transferring a NAK packet to the host device,
- transferring USB-compliant OUT packet and DATA packet, which are supplied from a host device side, to a function device, and (ii) transfering the handshake packet, which is a response to the USB-compliant OUT packet and DATA packet, to the host device side,
- a transfer rate for receipt of the OUT packet and the DATA packet from a host-side controller and a transfer rate for transmission of the handshake packet to the host-side controller are lower than a transfer rate defined by USB standard, and a transfer rate for transmission of the OUT packet and the DATA packet to the function device and a transfer rate regarding receipt of the handshake packet from the function device are identical with the transfer rate defined by USB standard,
- confirming amounts of data of the OUT packet and the DATA packet at a time of storing the OUT packet and the DATA packet in the storage means is additionally provided, the OUT packet and the DATA packet being supplied from the host-side controller, and
- transmitting the OUT packet and the DATA packet to the function device, when the amounts of data confirmed by the data amount confirming means exceed a predetermined value.
5 more elements
A packet-based communication program which causes a computer to perform as means of a communication controller which acts, when an OUT transaction is performed as data communication under USB standard, as a host-side controller that (i) transfers an OUT packet and a DATA packet, which are supplied from a host device, to a function device side, while (ii) transfers a handshake packet, which is a response to the OUT packet and the DATA packet, to the host device,
- the communication controller comprising:
- receipt acknowledgement means for acknowledging receipt of the OUT packet and the DATA packet from the host device;
- storage means for storing the handshake packet supplied from the function device side;
- data storage acknowledgement means for checking if the handshake packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of the OUT packet and the DATA packet from the host device;
- and
- transmission control means for (I) transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is not stored, and for (II) transmitting the handshake packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is stored,
- wherein, the communication controller also acts as a function-side controller which (i) transfers USB-compliant OUT packet and DATA packet, which are supplied from a host device side, to a function device, and (ii) transfers the handshake packet, which is a response to the USB-compliant OUT packet and DATA packet, to the host device side,
- a transfer rate for receipt of the OUT packet and the DATA packet from a host-side controller and a transfer rate for transmission of the handshake packet to the host-side controller are lower than a transfer rate defined by USB standard, and a transfer rate for transmission of the OUT packet and the DATA packet to the function device and a transfer rate regarding receipt of the handshake packet from the function device are identical with the transfer rate defined by USB standard,
- data amount confirming means for confirming amounts of data of the OUT packet and the DATA packet at a time of storing the OUT packet and the DATA packet in the storage means is additionally provided, the OUT packet and the DATA packet being supplied from the host-side controller, and
- the transmission control means starts to transmit the OUT packet and the DATA packet to the function device, when the amounts of data confirmed by the data amount confirming means exceed a predetermined value.
7 more elements
A storage medium storing a packet-based communication program which causes a computer to perform as means of a communication controller which acts, when an OUT transaction is performed as data communication under USB standard, as a host-side controller that (i) transfers an OUT packet and a DATA packet, which are supplied from a host device, to a function device side, while (ii) transfers a handshake packet, which is a response to the OUT packet and the DATA packet, to the host device,
- the communication controller comprising:
- receipt acknowledgement means for acknowledging receipt of the OUT packet and the DATA packet from the host device;
- storage means for storing the handshake packet supplied from the function device side;
- data storage acknowledgement means for checking if the handshake packet is stored in the storage means when the receipt acknowledgement means acknowledges the receipt of the OUT packet and the DATA packet from the host device;
- and
- transmission control means for (I) transmitting a NAK packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is not stored, and for (II) transmitting the handshake packet to the host device, when the data storage acknowledgement means confirms that the handshake packet is stored,
- wherein, the communication controller also acts as a function-side controller which (i) transfers USB-compliant OUT packet and DATA packet, which are supplied from a host device side, to a function device, and (ii) transfers the handshake packet, which is a response to the USB-compliant OUT packet and DATA packet, to the host device side,
- a transfer rate for receipt of the OUT packet and the DATA packet from a host-side controller and a transfer rate for transmission of the handshake packet to the host-side controller are lower than a transfer rate defined by USB standard, and a transfer rate for transmission of the OUT packet and the DATA packet to the function device and a transfer rate regarding receipt of the handshake packet from the function device are identical with the transfer rate defined by USB standard,
- data amount confirming means for confirming amounts of data of the OUT packet and the DATA packet at a time of storing the OUT packet and the DATA packet in the storage means is additionally provided, the OUT packet and the DATA packet being supplied from the host-side controller, and
- the transmission control means starts to transmit the OUT packet and the DATA packet to the function device, when the amounts of data confirmed by the data amount confirming means exceed a predetermined value.
7 more elements
A host-side controller which is provided in a host of a USB system and relays communications between the host and a device,
- at a time of performing a SETUP transaction, the host-side controller supplying, to a device side, a SETUP packet and a DATA packet supplied from the host, and storing the SETUP packet and the DATA packet on receipt of an ACK packet which is supplied from the device side towards the host, and
- the host-side controller comprising a host-side control section which supplies the ACK packet to the host on receipt of the SETUP packet and the DATA packet retransmitted from the host towards the device.
A USB system, comprising:
- a host;
- a device;
- a host-side controller;
- and
- a device-side controller,
- the host-side controller being provided in the host of the USB system and relaying communications between the host and the device,
- the host-side controller including a host-side control section which, at a time of performing a SETUP transaction, (i) transmits, to a device side, a SETUP packet and a DATA packet supplied from the host, (ii) stores an ACK packet transmitted from the device side towards the host, when the ACK packet is supplied, and (iii) supplies the ACK packet to the host, when the SETUP packet and the DATA packet retransmitted from the host towards the device is supplied, and
- the device-side controller being provided in the device and relaying communications between the host and the device.
5 more elements
A communication controller which relays communications between a host and a device and can act both as a controller on a host side and a controller on a device side,
- when the communication controller acts as the controller on the host side and a SETUP transaction is performed, the communication controller supplying, to the device side, a SETUP packet and a DATA packet supplied from the host, and storing an ACK packet transmitted from the device side towards the host, at a time of supply of this ACK packet to the communication controller, and
- the communication controller including a control section which supplies the ACK packet to the host, when the SETUP packet and the DATA packet which are retransmitted from the device side towards the host is supplied to the communication controller.
A packet-based communication method for exchanging packets between a host and a device of a USB system, comprising the steps of:
- at a time of performing a SETUP transaction,
- (i) transmitting, to a device side, a SETUP packet and a DATA packet supplied from the host;
- (ii) avoiding transfer of an ACK packet to a host side, the ACK packet being transmitted from the device side towards the host;
- and
- (iii) when the SETUP packet and the DATA packet are retransmitted from the host to the device, supplying the ACK packet to the host.
2 more elements
A packet-based communication program which causes a computer provided in a host of an USB system to execute a packet-based communication method for exchanging packets between the host and a device of the USB system,
- the method comprising the steps of:
- at a time of performing a SETUP transaction,
- (i) transmitting, to a device side, a SETUP packet and a DATA packet supplied from the host;
- (ii) avoiding transfer of an ACK packet to a host side, the ACK packet being transmitted from the device side towards the host;
- and
- (iii) when the SETUP packet and the DATA packet are retransmitted from the host to the device, supplying the ACK packet to the host.
3 more elements
A storage medium, storing a packet-based communication program which causes a computer provided in a host of an USB system to execute a packet-based communication method for exchanging packets between the host and a device of the USB system,
- the method comprising the steps of:
- at a time of performing a SETUP transaction,
- (i) transmitting, to a device side, a SETUP packet and a DATA packet supplied from the host;
- (ii) avoiding transfer of an ACK packet to a host side, the ACK packet being transmitted from the device side towards the host;
- and
- (iii) when the SETUP packet and the DATA packet are retransmitted from the host to the device, supplying the ACK packet to the host.
3 more elements
Dependencies are inferred from the claim text.