System and method for communicating information from a communications link to a host using a universal serial bus

A modem operable to communicate information from a communications link to a host using a universal serial bus, the modem comprising:

• a single receive memory operable to store all ATM cells received from the communications link;
• a receive manager operable to receive a plurality of ATM cells from the communications link and to store the ATM cells in the receive memory, the receive manager further operable to format the ATM cells into universal serial bus packets, and to transmit the universal serial bus packets to the host;
• and
• a short packet instigator operable to determine whether each ATM cell contains a termination condition associated with the content of the ATM cell, and in response to determining that an ATM cell contains a termination condition, to instigate transmission of a short packet comprising a universal serial bus packet carrying less than its capacity.

A method of communicating information from a communications link to a host using a universal serial bus, the method comprising:

• receiving a plurality of ATM cells from the communications link;
• storing each ATM cell in a modem memory;
• formatting the plurality of ATM cells into USB packets;
• examining each ATM cell for a termination condition associated with the content of the ATM cell;
• determining that one of the plurality of ATM cells contains a termination condition;
• in response to determining that one of the plurality of ATM cells contains a termination condition, instigating transmission of a short packet comprising a universal serial bus packet carrying less than its capacity;
• if no termination condition has been instigated, transmitting each USB packet to the host as soon as the USB packet is full;
• and
• transmitting a short packet to the host upon instigation of a short packet.

A method of communicating information from a communications link to a host using a universal serial bus, the method comprising:

• receiving an ATM cell from the communications link;
• determining a remaining capacity of a host buffer;
• determining whether a packet timer has expired;
• determining whether the ATM cell contains a termination condition associated with the content of the ATM cell;
• and
• instigating transmission of a short packet comprising a universal serial bus packet carrying less than its capacity if the remaining capacity of the host buffer is less than or equal to one ATM cell, or if the packet timer has expired, or if the ATM cell contains a termination condition.