Abstract: Aspects of the disclosure relate to an apparatus having a travel height truss including a frame suitable for transporting an item. The apparatus includes a boom which may be raised from the frame. The boom is raised and lowered by a hydraulic system comprising a travel height truss. The travel height truss may comprise two portions, telescopically connected to each other, one portion pivotably connected to the frame and the other pivotably connected to the boom. The travel height truss provides greater leverage than would otherwise be available for the maximum size and weight of the load available for a given (fixed) maximum length of trailer. In this manner, the boom frame can be raised to greater heights, while maintaining horizontal distance, than otherwise.

Abstract: Switched pull down (SPD) ECL circuits have a switching circuit within the pull down portion of the output stage, so that a large portion of the total pull down current is switched to the negative going output node, and so that a small portion of the total pull down current is switched to the positive going output node. The negative going output node has a larger that normal ECL pull down current attached to it. The larger pull down current on the negative going node discharges the output capacitor in a shorter period of time. The shorter discharge time of negative going output results in a shorter fall delay time. Two smaller current sources are connected to each of the two differential ECL outputs to insure that both pull up transistors are forward biased so as to provide an adequate noise margin and insure correct circuit operation. Forward biasing the pull up transistors with a minimum acceptable amount of bias current at the emitters of the output pull up transistors provides proper immunity to noise.

Abstract: A specialized apparatus and method for providing fast programmed I/O for transferring information in a multi-processor environment which includes a CPU, and a memory coupled to an I/O port across an internal data bus. Multiple bytes of data are transferred in successive processing cycles to the I/O port from the memory, or from the I/O to the memory by first determining the upper limit for the number of bytes that are going to be transferred. This number and the memory start address are then stored in CPU registers. The I/O module is then checked by the CPU to see if a data byte is available from an external device. If a data byte is available, the I/O module is instructed to place the data byte on the bus for storage within the memory at the start address. The address is then incremented and the count is decremented. The above procedure is repeated until the count drops to zero, after which time the next instruction is fetched.

Abstract: A computer architecture and method capable of retaining data after a system clock has been halted to conserve power. The computer comprises first processing circuitry, the first circuitry comprising dynamic components. The dynamic components include such devices as intermediate pipeline registers, arithmetic logic units, address generators, and instruction decode and control circuitry. The computer further comprises second processing circuitry, the second circuitry comprising static components. In a preferred embodiment, the static components comprise instruction registers, stop controls, general purpose registers, status registers, and random access memory. The use of dynamic components in the architecture of a preferred embodiment maximizes cost and size considerations, while the static components allows instruction execution and the system clock to be halted.