Abstract: A protocol for local data transfers between a system manager for a computer system and a network operating system associated with the computer system and a method for exchanging command and response messages between the system manager and the network operating system using a bus master interface provided between the two. Various ones of the interface registers are reserved by the side transferring information, command written to the interface registers and the other side notified of the information transferred to the interface and the reservation released. The interface is also used to transfer responses to the side originating the command.

Abstract: A power supply for a computer system manager, wherein the power supply has its own secondary power source operable when input power to the system manager no longer meets preset threshold values. The power supply functions in one of a discrete number of power modes depending upon the amount of energy available from either the computer input power or the secondary power source. The power supply switches to one of the group of power modes to conserve secondary power when the computer input power is no longer available. The power modes are controlled by a power mode controller which selectively directs power to discrete components of the system manager as a power conservation technique. The power mode controller always energizes the random access memory of the system manager in order to maintain data integrity.

Abstract: A protocol for communicating messages between a manager for a computer system and a remote facility asynchronously connected with the system manager and a method for exchanging messages using the protocol. The protocol determines whether the system manager is ready to exchange messages with the remote facility, determines whether the remote facility is ready to exchange messages with the system manager and exchanges messages between the system manager and the remote facility. To exchange messages, a command message which includes a first field for identifying a command transmitted by the command message and a second field for identifying the command message is transmitted. In response, a command reply message which includes a first field for identifying the command to which the command reply message is in response to, a second field for matching the command response message to the command message and a third field for transmitting a response to the command message is transmitted.

Abstract: A sequencer control for controlling the time sequencing of the energization of controlled elements includes a microprocessor unit. A large number of input lines and output lines are uniquely multiplexed into a relatively small number of I/O terminals on the microprocessor. The multiplexing, the sequencing and all of the delays are effectively controlled by the microprocessor.