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公开(公告)号：JPH03148697A
公开(公告)日：1991-06-25
申请号：JP21053990
申请日：1990-08-10
Applicant: APPLE COMPUTER
Inventor： BURAIAN DEI HAWAADO , ROBAATO ERU BEIRII
Abstract: PURPOSE: To use various monitors by providing a programmable video circuit for transferring video data from a RAM to the monitor so as to supply video timing signals to the monitor and displaying the video data on the monitor. CONSTITUTION: Under the control of a CPU 13, a memory decoding unit MDU 12 receives video request signals from an RBV 14 and sends RAM control signals to the RAM 11. The RAM 11 sends the stored video data to the RBV 14. The RBV 14 receives frequencies A-C from the frequency sources 18-20 of the three different frequencies A-C and sends timing signals to the montior 27. Also, the RBV 14 supplies the video data through a bus 29 to a video A/D converter(VADC) 26. The VDAC 26 receives dot clock signals, composite blanking period signals and composite video synchronizing signals through signal lines 30, 31 and 33 and sends the color signals of RGB to the monitor 27. The monitor 27 displays images and sends monitor identification signals to the RBV 14.
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公开(公告)号：JPH03171317A
公开(公告)日：1991-07-24
申请号：JP23729490
申请日：1990-09-10
Applicant: APPLE COMPUTER
Inventor： AARU SUTEIIBUN SUMISU , MAIKU ESU HANRON , ROBAATO ERU BEIRII
Abstract: PURPOSE: To reduce the power consumption of a lap top computer by monitoring various devices and controlling the distribution of power to the various devices of the computer. CONSTITUTION: In order to economize the power of a battery 17 by cutting power supply to the device not to be used, a power managing device 11 continuously monitors various circuit functions. This power managing device 11 can be operated in three operating modes and in the 1st mode, a computer 10 is operated in an ordinary activity mode. Besides, the 2nd state is called sleep state, the computer 10 is turned into inactive state, and the power managing device 11 continuously monitors the various conditions of circuits. Further, the 3rd state is an intermediate state and in such a state, the power managing device 11 decreases the frequency of a clock signal so that the power consumption can be decreased for about 25%-30% rather than that of ordinary operating mode. Thus, the service life of the built-in battery can be prolonged so that the lap top computer 10 can be operated for a long time when external power is cut off.
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公开(公告)号：JPH03130798A
公开(公告)日：1991-06-04
申请号：JP21053890
申请日：1990-08-10
Applicant: APPLE COMPUTER
Inventor： ROBAATO ERU BEIRII , BURAIAN DEI HAWAADO
Abstract: PURPOSE: To improve system performance by determining the priority of access to a RAM and refusing the access from a CPU to the RAM during the read of video data from the RAM. CONSTITUTION: A CPU 13 of a system 10 executes a program for supplying the video data to a monitor 27. The monitor 27 is programmed as a matrix composed of plural pixels. Then, the pixels are expressed by a certain number of bits in the video data stored inside the system memory or a RAM 11 of the computer. Besides, a video integrated circuit is connected to the RAM 11 and supplies the video data for N bits per pixel to the monitor 27. In this case, the priority of access to the RAM 11 is determined so as to reduce the access from the CPU 13 to the RAM 11 by a memory controller while a video circuit reads data from the RAM 11. Thus, the need of communication with a video card is eliminated to improve system performance.
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