Personal Computer for Disabling Resume Mode Upon Replacement of HDD

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Personal Computer for Disabling Resume Mode Upon Replacement of HDD Europaisches Patentamt J) European Patent Office (") Publication number: 0 426 1 33 A2 Office europeen des brevets EUROPEAN PATENT APPLICATION © Application number: 90120837.1 © int. ci.5: G06F 3/06 © Date of filing: 30.10.90 © Priority: 31.10.89 JP 281738/89 © Applicant: Kabushiki Kaisha Toshiba 72, Horikawa-cho Saiwai-ku @ Date of publication of application: Kawasaki-shi(JP) 08.05.91 Bulletin 91/19 @ Inventor: Hibi, Kenji, c/o Intellectual Property ® Designated Contracting States: Division DE FR GB Kabushiki Kaisha Toshiba, 1-1 Shibaura 1-chome Minato-ku, Tokyo 105(JP) © Representative: Henkel, Feiler, Hanzel & Partner Mohlstrasse 37 W-8000 MUnchen 80(DE) © Personal computer for disabling resume mode upon replacement of HDD. © When a hard disk pack (20) is removed from a F/F (67) that the hard disk pack (20) has been computer main body in a power-OFF state, a signal replaced. The CPU (11) disables a resume flag. As a level of a specific pin of a connector (61) is set at result, upon a power-ON operation, resume process- high level, and a signal of high level representing ing is not performed, and damage to the hard disk replacement of the hard disk pack (20) is set in a pack and overrun of a program can be prevented. flip-flop (F/F) 67. When a power switch is turned on, a CPU (11) determines from information set in the + 5V :/71 HDCHG SIGNAL C4 < 73 CO CO 20 CLEAR SIGNAL Q- 111 F I G. 3 Xerox Copy Centre EP 0 426 133 A2 PERSONAL COMPUTER FOR DISABLING RESUME MODE UPON REPLACEMENT OF HDD The present invention relates to a personal puter having a detachable disk unit and a resume computer using a replaceable hard disk as an function, comprises the computer steps of: a) de- external storage medium. tecting and registering that the disk unit is de- In the field of personal computers in recent tached in a power-OFF state; b) when a power years, compact, lightweight, portable laptop per- 5 switch is turned on again, checking whether the sonal computers have been very popular in place disk unit is detached; and c) determining that the of conventional desk-top personal computers. De- disk unit is detached and invalidating the resume mand has increasingly arisen for more compact, function. lightweight, portable laptop personal computers. According to the present invention, a hard disk The most advanced laptop personal computer em- w pack replacement detector (powered from a bac- ploys a low-profile floppy disk drive (FDD), and a kup power source) detects replacement of a hard display and a hard disk pack are detachably moun- disk pack in a power-OFF state, and this informa- ted in this personal computer. tion is stored as status information in a memory In order to improve user operability, a laptop backed up by a battery. When the power switch is personal computer has a resume mode as a stan- 75 turned on, a CPU checks the status information, dard mode. In the resume mode, a state (i.e., a detects replacement of the hard disk unit, releases content of a memory and contents of various types the resume mode, and causes a display to display of register) in the system is saved in a nonvolatile an alarm message to an operator. memory in a power-OFF state, and a state imme- This invention can be more fully understood diately before the power-OFF timing is restored 20 from the following detailed description when taken upon power-ON. Therefore, jobs can be continued in conjunction with the accompanying drawings, in regardless of a power-ON/OFF state. which: A hard disk pack is generally replaced in a Fig. 1 is a system block diagram showing an power-OFF state to prevent attachment/detachment overall arrangement of a personal computer ac- of the hard disk pack while signal lines are kept 25 cording to the present invention; active. In the above personal computer, however, if Fig. 2 is a block diagram showing a main part of a hard disk pack is detachable and when it is the present invention; replaced in a power-OFF state, a change in content Fig. 3 is a circuit diagram showing a detailed of the hard disk pack is not detected and a job is arrangement of a hard disk pack replacement resumed in a resume mode. Therefore, the content 30 detector shown in Fig. 2; of the hard disk pack is broken, and a system may Fig. 4 is a flow chart showing a power-ON overrun. control program executed by a CPU 1 1 ; It is an object of the present invention to pro- Fig. 5 is a flow chart showing SETUP process- vide a personal computer, wherein replacement of ing for setting a resume flag; and a hard disk pack in a power-OFF state is detected, 35 Figs. 6 and 7 are flow charts showing resume and a resume mode is disabled to prevent the processing. content of the hard disk pack from damage and a Fig. 1 is a system block diagram showing an program from overrun. overall arrangement of a personal computer ac- According to the first aspect of the present cording to the present invention. invention, a personal computer comprises: means 40 Referring to Fig. 1, components 11 to 28, 51, for supplying a power to the personal computer; and 53 are connected to a system bus 10. The external storage medium means- detachably con- central processing unit (CPU) 1 1 controls the over- nected to the personal computer; resume means all system and executes flow charts shown in Figs. for resetting a system to an immediately preceding 4 to 7. The CPU 11 serves as a host CPU when state of a power-OFF operation in response to a 45 viewed from a power control CPU 306 in a power power-ON operation after a power switch is turned supply 30 (to be described later). The read only off; status register means for detecting and regis- memory (ROM) 12 stores a basic input and output tering that the external storage medium means is program (BIOS). The BIOS includes programs replaced in the power-OFF state; and control shown in Figs. 4 to 7 and is executed in response means for referring to the status register means 50 to a system power supply. Setup information when the power switch is turned on and invalidat- stored in a specific area (or register) of the RAM 13 ing the resume means when the external storage is loaded, and a system atmosphere is judged. A medium means is determined to be replaced. boot block is loaded from the HDD 20A, and an According to the second aspect of the present operating system (OS) program stored in the HDD invention, a method for controlling a personal com- 20A is loaded in the RAM 13 by this boot block. EP0 426 133 A2 The random access memory (RAM) 13 stores the in the personal computer main body to rectify and operating system (OS), application programs, and smooth a commercial AC power and obtain a DC various data. A backup power supply voltage VBK operating power having a predetermined voltage. is supplied from the power supply 30 to the RAM An expansion unit is selectively connected to an 13. Even if a system power switch is turned off, the 5 expansion connector 40. The intelligent power sup- memory contents are not lost. The direct memory ply (power controller) 30 comprises the power con- access (DMA) controller 14 performs direct mem- trol CPU 306 and supplies power to each unit ory access control. The controller (PIC) 15 is a described above. A battery (M-BATT) 31 A is a programmable interrupt controller which can be set detachable main battery pack constituted by a re- by a program. The timer (PIT) 16 is an interval w chargeable battery. A battery (S-BATT) 31 B is a timer which can be set by a program. When the sub-battery incorporated in the main body and con- interval timer 16 counts a time set by a program, stituted by a rechargeable battery. the timer 16 supplies a time-out signal as an inter- Fig. 2 is a block diagram showing a relation- rupt signal to the CPU 1 1 under the control of the ship between the hard disk pack 20, the hard disk programmable interrupt controller 15. The CPU 11 15 pack replacement detector 53, and the CPU 11. executes a vector interrupt routine in response to When the hard disk pack 20 is replaced in the this interrupt signal. The real-time clock (RTC) 17 power-OFF state, the hard disk pack replacement is a timepiece module having its own operation detector 53 detects it and registers it as status battery to display current time. The extending RAM information. Upon a power-ON operation, the CPU 1 8 is a large-capacity memory detachably mounted 20 11 reads the status information stored in the hard in an extending RAM card slot in a main body, and disk pack replacement detector 53 and determines a backup power (VBK) is supplied to the extending whether the hard disk pack is replaced in the RAM 18. The backup RAM 19 constitutes a data power-OFF state. storage area for realizing the resume function and Fig. 3 is a circuit diagram showing a detailed is supplied with the backup power (VBK). The hard 25 arrangement of the hard disk pack replacement disk interface 51 interfaces the CPU 11 with the detector 53.
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