Abstract: In a system including a host, at least one peripheral and a peripheral repeater having a transmitter/receiver for the peripheral, with the peripheral repeater receiving messages from the peripheral and retransmitting them to the host and receiving messages from the host and retransmitting the messages to the peripheral when a change in baud rate is desired, a message is sent from the host to the peripheral, through said peripheral repeater to set a new baud rate, another message is sent from the host to the peripheral repeater to change the baud rate of the transmitter/receiver and the baud rate of the peripheral which was set is maintained in a table in the host.

Abstract: In a system including a host and a peripheral repeater having at least one peripheral coupled thereto, data from the peripheral is packetized at the peripheral repeater and sent to the host. This is done by establishing a baud rate for the peripheral, accumulating messages from the peripheral into packets and terminating and transmitting a packet. The terminating and transmitting is performed if a predetermined time based on the baud rate passes without receiving a byte from the peripheral.

Abstract: In a system which includes a data transmitting device, a repeater, and a data receiving device, the repeater accumulating input data in packets from the transmitting device and retransmitting it to the receiving device, a memory structure for the data which includes a data buffer a receive queue having a plurality entries, each entry capable of storing the starting address of a packet in the data buffer in order of receipt, and a transmit queue for storing the starting addresses of packets for transmitting to said receiving device is provided in the repeater. In operation, only addresses are transferred from receive queue to transmit queue with the data remaining in the buffer. Preferably the buffer and queues are circular.

Abstract: In a system including a processor and at least one connector for providing inputs to the processor, which one of a plurality of different types of peripherals is plugged into the connector is determined by sensing any change in the connection of a peripheral to said connector, upon initial start-up of the system and each time a change from not plugged in to plugged in is detected interrogating the peripheral to obtain its type and storing the type of peripheral which is plugged in.

Abstract: A method of communicating between two control units includes transmitting a message from one control unit to the other, checking the message at the other control unit for proper reception, if the reception is not proper, sending a NAK signal from the other to the one control unit, if the reception is proper, sending an ACK signal from the other to the one control unit, and upon receiving an NAK at said one control unit, resending the original message.