High speed modem

Claim 2

Apparatus for communication of data over a telephone line, characterized by: a transmit data buffer for accepting digital data; a transmitter receiving data from the transmit data buffer, for placing a transmit signal on a telephone line; said transmitter being selectively operable in either a lower-speed, full-duplex mode or a higher­speed, half-duplex mode in response to a mode control command; and a control circuit for monitoring the amount of data being placed in the transmit data buffer and producing the mode control command to the transmitter to establish the mode of transmitter operation based upon the data transmission demand.

Claim 3

Apparatus for communication of data over a telephone line to a remote data receiver, characterized by: a transmit data buffer for holding data; a transmitter receiving data from the transmit data buffer, for placing a transmit signal on a telephone line to communicate data and control frames; said transmitter being selectively operable in either a lower-speed, full-duplex mode or a higher-­speed, half-duplex mode in response to a control command; and a control circuit coupled to the transmitter, for providing a control frame to be sent by the transmitter to the remote data receiver to signal higher-speed operation and producing the control command to the transmitter to select the higher-speed, half-duplex mode based upon the amount of data in the transmit data buffer.

Claim 4

Apparatus for communication of data over a telephone line to a remote data receiver, characterized by: a transmit data buffer for holding data; a transmitter receiving data from the transmit data buffer, for placing a transmit signal on a telephone line to communicate data and control frames; said transmitter being selectively operable in either a lower-speed, full-duplex mode or a higher-­speed, half-duplex mode in response to a control command; and a control circuit coupled to the transmitter, for providing a control frame to be sent by the transmitter to the remote data receiver to signal higher-speed operation and producing the control command to the transmitter to select the higher-speed, half-duplex mode based upon the amount of data in the transmit data buffer.

Claim 5

The mode of claim 2 characterized in that said control circuit further provides a control frame to be sent by the transmitter to the remote data receiver to signal lower-speed operation and producing the control command to the transmitter to select the lower-speed, full-duplex mode.

Claim 6

Apparatus for communication of data over a telephone line between a local data terminal and a remote modem, characterized by: a transmitter for accepting data and control frame information and placing a transmit signal on a telephone line; said transmitter being selectively operable in either a lower-speed, full-duplex mode or a higher-­speed, half-duplex mode in response to a control command; a receiver for accepting a transmit signal of link control frame from a remote modem over the telephone line and providing a receive signal of control frame information; a transmit data buffer for accepting data from a local data terminal; a control circuit coupled to the transmitter to provide control frame information and the mode control command, and coupled to the receiver to obtain the receive signal of control frame information; and the control circuit for providing the mode control command to the transmitter to select the lower-­speed, full-duplex mode during an exchange of control frame information with a remote modem, and for thereafter monitoring the transmit data buffer and providing a mode control command to the transmitter to select the higher-speed, half-duplex mode based upon the data trans­mission demand.

Claim 7

Apparatus for communication of data over a telephone line between a local data terminal and a remote modem, characterized by: a transmitter for accepting data and control frame information and placing a transmit signal on a telephone line; said transmitter being selectively operable in either a lower-speed, full-duplex mode or a higher-­speed, half-duplex mode in response to a control command; a receiver for accepting a transmit signal of link control frame from a remote modem over the telephone line and providing a receive signal of control frame information; a transmit data buffer for accepting data from a local data terminal; a control circuit coupled to the transmitter to provide control frame information and the mode control command, and coupled to the receiver to obtain the receive signal of control frame information; and the control circuit for providing the mode control command to the transmitter to select the lower-­speed, full-duplex mode during an exchange of control frame information with a remote modem, and for thereafter monitoring the transmit data buffer and providing a mode control command to the transmitter to select the higher-speed, half-duplex mode based upon the data trans­mission demand.

Claim 8

A modem for providing communication of data over a telephone line between a local data terminal and a remote modem, characterized by: a transmitter for accepting data and control frame information and placing a transmit signal on a telephone line to the remote modem; said transmitter being selectively operable in either a lower-speed, full-duplex mode or a higher-­ speed, half-duplex mode in response to a control command; a receiver for accepting a transmit signal from a remote data communication unit over the tele­phone line in either a higher-speed, half-duplex mode or a lower-speed, full-duplex mode in response to a mode control command and providing a receive signal; a transmit data buffer for accepting data from a local data terminal; a processor coupled to the transmitter and the receiver and providing mode control commands thereto; the processor controlling transmitter and receiver operation during a connect sequence with a remote modem to effect an exchange of control frame information therebetween and thereafter controlling transmitter and receiver operation to effect data communication with the remote modem based upon the data transmission demands by monitoring the data going to the transmit data buffer and providing a mode control command to the transmitter to select the higher-speed, half-duplex mode upon determining a predeter­mined number of characters in the buffer for communication and providing a mode control command to the transmitter to select the lower-­speed, full-duplex mode upon determining that insufficient data is in the buffer to require higher-speed operation.

Claim 9

A modem for providing communication of data over a telephone line between a local data terminal and a remote modem, characterized by: a transmitter for accepting data and control frame information and placing a transmit signal on a telephone line to the remote modem; said transmitter being selectively operable in either a lower-speed, full-duplex mode or a higher-­ speed, half-duplex mode in response to a control command; a receiver for accepting a transmit signal from a remote data communication unit over the tele­phone line in either a higher-speed, half-duplex mode or a lower-speed, full-duplex mode in response to a mode control command and providing a receive signal; a transmit data buffer for accepting data from a local data terminal; a processor coupled to the transmitter and the receiver and providing mode control commands thereto; the processor controlling transmitter and receiver operation during a connect sequence with a remote modem to effect an exchange of control frame information therebetween and thereafter controlling transmitter and receiver operation to effect data communication with the remote modem based upon the data transmission demands by monitoring the data going to the transmit data buffer and providing a mode control command to the transmitter to select the higher-speed, half-duplex mode upon determining a predeter­mined number of characters in the buffer for communication and providing a mode control command to the transmitter to select the lower-­speed, full-duplex mode upon determining that insufficient data is in the buffer to require higher-speed operation.

Claim 10

The modem of claim 5 characterized in that the processor further monitors the receive signal to determine a request by the remote modem for higher-speed operation and provides a control command to the receiver to accept the remote modem transmit signal in a higher-speed, half-­duplex mode.

Claim 11

The modem of claim 5 characterized in that the processor further monitors the receive signal to determine a request by the remote modem for lower-speed operation and provides a control command to the receiver to accept the remote modem transmit signal in a lower-speed, full­duplex mode.

Claim 12

Apparatus for providing communication of data over a telephone line, characterized by: a transmitter receiving frames of data, for placing a transmit signal on a telephone line; said transmitter being selectively operable to transmit data at discrete data rates in response to a speed control command; a processor for monitoring the transmission of data frames to determine data transmission errors, and for producing the speed control command to select the data rate of the transmitter; and said processor causing the data transmission rate to fallback to a lower data rate or to fallforward to a higher data rate based upon the determina­tion of data transmission errors.

Claim 13

Apparatus for providing communication of data over a telephone line, characterized by: a transmitter receiving frames of data, for placing a transmit signal on a telephone line; said transmitter being selectively operable to transmit data at discrete data rates in response to a speed control command; a processor for monitoring the transmission of data frames to determine data transmission errors, and for producing the speed control command to select the data rate of the transmitter; and said processor causing the data transmission rate to fallback to a lower data rate or to fallforward to a higher data rate based upon the determina­tion of data transmission errors.

Claim 14

The apparatus of claim 8, characterized in that the processor determines data transmission errors based upon the retransmissions of data frames.

Claim 15

Apparatus for communication of data over a telephone line, characterized by: a receiver for accepting a transmit signal of data or control frame information over the telephone line and providing a receive signal; said receiver being selectively operable to accept a transmit signal in either a higher-speed, half-­duplex mode or a lower-speed, full-duplex mode in response to a mode control command; and a control circuit coupled to the receiver to obtain the receive signal of control frame information, said control circuit for providing the mode control command to the receiver to select the lower-­speed, full-duplex mode or the higher-speed, half-duplex mode based upon a receive signal of control frame information.

Claim 16

Apparatus for communication of data over a telephone line, characterized by: a receiver for accepting a transmit signal of data or control frame information over the telephone line and providing a receive signal; said receiver being selectively operable to accept a transmit signal in either a higher-speed, half-­duplex mode or a lower-speed, full-duplex mode in response to a mode control command; and a control circuit coupled to the receiver to obtain the receive signal of control frame information, said control circuit for providing the mode control command to the receiver to select the lower-­speed, full-duplex mode or the higher-speed, half-duplex mode based upon a receive signal of control frame information.

Claim 17

The apparatus of claim 10 further characterized by: a transmitter for placing a transmit signal on a telephone line.