Abstract: Provided are a portable input device for inputting coordinates, a method of calibrating the device, and a computer readable recording medium storing a computer program for making a computer perform the method. The portable input device includes two digital cameras, a calibration tool, a storage section, and a controller for calculating coordinates of an object on an input surface based on images taken by the two digital cameras based on images taken by the two digital cameras so as to include the calibration tool. The controller also calibrates positions and widths of a detection band which corresponds to a detection zone defined in a vicinity of the input surface. The positions and the widths of the detection band are stored in the storage section in relationship to positions on the input surface.

Abstract: Provided are a portable input device for inputting coordinates, a method of calibrating the device, and a computer readable recording medium storing a computer program for making a computer perform the method. The portable input device includes two digital cameras, a calibration tool, a storage section, and a controller for calculating coordinates of an object on an input surface based on images taken by the two digital cameras based on images taken by the two digital cameras so as to include the calibration tool. The controller also calibrates positions and widths of a detection band which corresponds to a detection zone defined in a vicinity of the input surface. The positions and the widths of the detection band are stored in the storage section in relationship to positions on the input surface.

Abstract: A controller for use with an image formation device. An image formation system includes an image formation device and a controller associated with the image formation device. The image formation device can be operated in either copier mode or printer mode. In printer mode, the controller receives print jobs and forwards the print jobs to the image formation device. The controller converts the print jobs to pixel data and stores the pixel data in memory to buffer the print jobs. The controller also interprets print commands and controls functions performed by the image formation device.

Abstract: A process for identifying disks and automatically configuring a disk drive system to any one of a variety of disk patterns as embedded in firmware in a controller of a disk drive system. The process distinguishes between embedded servo and nonembedded servo disks by searching for servo patterns on the disk. Distinction between high and low density type disks is made by reading the disks at different data rates. After the type of disk is determined, a controller is enabled to set the disk drive system in the proper mode for that type of disk. The process also enables the controller to find the disk format values on the disk, or provides the standard values for the particular type of disk if the information is not located on the disk.

Abstract: A process allows a disk drive system to optimize head position in order to minimize the effects of track variations due to disk misclamping and imperfections. The process utilizes a transducer head having a width less than a track width. The small size of the transducer head allows it to be positioned within a stationary band which remains within the boundaries of the track for the complete revolution of the disk. Once the head is positioned within this band for one track of the disk, this track can be used as a reference for positioning the head within the bands of the other tracks.

Abstract: In a digital information storage system or the like, start up power sequencing for independently operable machines such as disk drives each equipped with a microprocessing unit is provided through a simplified power sequencing circuit. The power sequencing circuit is operatively coupled with an independent preprogrammable micropocessing unit in each machine and to a single control line common to all disk drives. The microprocessing unit is preprogrammed to interact with the power sequencing circuit to provide Enable/Disable signals to the control line and to sense the state of the control line. In particular, the microprocessing unit executes a preprogrammed sequence of steps in interaction with the control line to sequence the start-up of each spindle motor irrespective of the number of disk drives coupled to the control line, thereby preventing electrical power overload.

Abstract: A method and apparatus for accessing data blocks in a computer system having multiple-disk drive rotational position sensing which is not centrally synchronized and where data read and write requests are normally weighted by the order of availability of requested data blocks. The weighting of the priority, or queue position, of selected data blocks is modified by advancing the apparent initial location of data blocks designated for preferental access and maintaining an availability signal, or peripheral interrupt, for an extended period. A special pre-data-transfer instruction indicates the duration of the peripheral interrupt. A circuit for implementing the invention has a storage register for receiving the special instruction, a down counter for decrementing for the duration of the designated pre-data-interrupt and an interrupt duration control latch for issuing and extinguishing the interrupt.