Abstract:
In a computer system having a flat panel as standard equipment and allowing a CRT as an optional unit to be connected thereto, first test data common to R, G, and B in all the palettes in a RAMDAC, and each of the R, G, and B display signal levels output from the RAMDAC is compared with a reference level to determine whether a color CRT is connected. Furthermore, in all the palettes in the RAMDAC, the same data as the first test data is written for G, and data smaller than the first test data is written for R and B, and each of the R, G, and B display signal levels output from the RAMDAC is compared with the reference level to determine whether a monochrome CRT is connected.
Abstract:
The present invention provides a cache system comprising a cache memory in which the number of write cycles to a disk is decreased by using write command receiving bits in the entries of a directory memory (35) and by using a specified write instruction designation bit in the W-command in such a way, that in the case of a specified W-command it is checked if there are N or more entries whose write command receiving bits are set, i.e. if there are N or more blocks which have been written in cache memory but not yet in the disk, so that, if a cache hit is detected in the case of the disk write command whose specified write construction designation bit is set, the corresponding write data is registered only in the cache if the number of blocks not written in the disk is smaller than N. In this way a disk write operation is always performed in response to a disk write instruction from a host system, even in the case that the cache hit occurs.
Abstract:
A recorded data reproducing apparatus according to this invention comprises a data pulse generation section (l0 to l5), a peak detection section (l7 to l9) and a control section (20 to 22). The data pulse generation section (l0 to l5) reads out data written on the cylinder of a recording medium on which a magnetic head is currently positioned. According to received gain data, the data pulse generation section (l0 to l5) amplifies a signal corresponding to the readout data, and selectively generates data pulse sequence based on the amplified signal. When the amplified signal corresponds to servo data, the peak detection section (l7 to l9) detects the peak value of the amplified signal. The control section (20 to 22) determines whether or not the magnitude of the detected peak value is nearly equal to a predetermined value. If the determination is negative, the control section (20 to 22) refers to a gain data table to determine a change amount of the gain data, and supplies the gain data updated based on the change amount to the data pulse generation section (l0 to l5).
Abstract:
According to a magnetic disk controller incorporating a disk cache system, an arbitrary LRU value and a resident bit for inhibiting replacement of a corresponding block are added to a read/write command. Each entry of a directory memory (35 1 ) has a disk block address field, an LRU counter for storing the arbitrary LRU value, a write command receiving bit field representing non- writing of write data in the disk unit, the write data being accessed by the host system, a resident bit field for inhibiting replacement of the corresponding block, and a disk drive identifier field (LUN) representing the corresponding magnetic disk drive unit (10, through 10 4 ). The LRU setting value added to the read/write command is registered in the LRU counter field of the entry corresponding to the block to be replaced. If the number of data is smaller than a maximum number of blocks to be written in the disk unit, writing is performed for the corresponding block in the cache memory. The resident bit of the entry to be replaced is set/reset in response to the read instruction. If a read error occurs, the cache block to be replaced is divided into subunits on the basis of a sector next to that the number of which is read, a start sector fo the disk area data which is to be transferred to the host system, and a last sector thereof. A transfer start cache address, the number of transfer sectors, and a data transfer direction control code are produced for each one of the subunits of the cache block to be replaced. The directory memory is commonly used by a plurality fo magnetic disk units.
Abstract:
A rectangular flat box-like main body of the card-shaped electronic device can be inserted into and taken out of an electronic apparatus in a given insertion direction. The main body has a pair of lateral sides extending in the insertion direction. A pair of shield plates (154) are fixed to the main body to cover the upper and lower surfaces of the main body. Each shield plate is formed of a metal and includes a bent portion which is fitted on a lateral side of the main body and constitutes a conductive portion (160) for conducting the shield plates with the electronic apparatus when the main body is loaded in the electronic apparatus.
Abstract:
A personal computer includes a box-shaped body (1) having a card storing section (108) for storing a memory card. An operating opening portion (105) is formed by cutting an edge of the body to a given size and externally accessible by a finger, and the storing section communicates with the opening portion through an inlet opening (107). An ejector mechanism (115) for ejecting the card from the card storing section includes a card receiver (116) arranged in the storing section for receiving the card inserted through the inlet opening. A drawer member (125) is mounted on the card receiver and has an operating end portion. The operating end portion is located within the operating opening portion when the drawer member is moved to its pushed-in position while the card receiver is in its first position and outwardly projects through the operating opening portion when the drawer member is moved to its drawn-out position while the card receiver is in its first position. When the drawer member is drawn outside the body form its drawn-out position, the card receiver along with the received card is moved from its first position to its second position in accordance with the movement of the drawer member.