JPH04258848A - Method and mechanism for controlling spindle motor drive of magnetic disk device - Google Patents

Abstract

PURPOSE:To alleviate trouble and malfunction immediately after inputting a power source due to abnormal temp. in the magnetic disk device. CONSTITUTION:A temp. measuring circuit 70 is supplied with its power source from a battery, and is operated even under the cut-off state of the device power source, so as to measure and store the temp. inside an HDA(head disk assembly) 30 by a temp. sensor 71 for a fixed period, and such temp. information in a fixed period of time is held. A microprocessor circuit 10 is operated upon input of the device power source, and the temp. information before the input of the power source is inputted from the temp. measuring circuit 70 in accordance with a sequence of a control memory circuit 20. Subsequently, the inputted temp. information is compared with a predetermined condition, and if it is satisfied with the condition, the drive processing of the spindle motor 31 is executed as the normal sequence, and if not satisfied with the condition, the sequence is returned to input of the temp. information again, and until it is satisfied with the condition, the spindle motor is kept under stopping state.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk drive, and more particularly to a spindle motor drive control method and mechanism when power is turned on.

0002

2. Description of the Related Art Conventional magnetic disk drives operate the spindle motor after power is turned on, regardless of the internal temperature of the head disk assembly (hereinafter abbreviated as "HDA"), or based only on the current internal temperature of the HDA. I was in control.

0003

[Problems to be Solved by the Invention] In the above-described conventional spindle motor drive control method for magnetic disk drives, the internal temperature of the HDA is unknown until the start of motor drive, so the motor is driven while the head is stuck due to dew condensation, etc. Or, because the temperature is significantly different from the recommended temperature, there is a risk that the equipment may malfunction due to thermal off-track. Also the current HD
A Even when determining motor drive based only on internal temperature, past temperature changes are unknown, so if the disk medium/head is HD
Unlike the temperature inside A, the above-mentioned failure may occur.

0004

[Means for Solving the Problems] In the spindle motor drive control method for a magnetic disk drive of the present invention, after the power is turned on and before starting motor drive in response to a start command, a temperature measurement circuit collects HDA internal temperature information before the start command is received. A spindle motor drive control method for a magnetic disk device, characterized in that temperature information is input and compared with motor drive conditions, and if the temperature information satisfies the motor drive conditions, motor drive is started, the method comprising: There is. (A) Process of inputting current and past HDA internal temperature information from the temperature measurement circuit. (B) Process of comparing input temperature information with motor drive conditions. (C) A process of determining whether to execute or suspend motor drive based on the comparison made in section (B).

Further, the spindle motor drive control mechanism of the magnetic disk drive of the present invention includes an interval timer, a register into which temperature data measured by a temperature measuring element is input each time the timer is set, and past temperature data (temperature data). a temperature measuring circuit comprising a register in which temperature information) is stored and the temperature information is updated every time temperature measurement is made; a battery that supplies power to the temperature measuring circuit; and a temperature measuring circuit that stores temperature information input from the temperature measuring circuit. A memory that stores data to compare temperature information, a register that stores the comparison results, and a register value to select whether to proceed to motor drive execution processing or return to temperature comparison processing again. It is equipped with a microprocessor circuit consisting of a selector.

[0006]

[Embodiment] Next, an embodiment will be explained with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention, in which an MPU microprocessor 10 is connected to a SERVO-CT connected via an MPU-BUS according to a control program written in an FWM control memory circuit 20.
It writes and reads data to and from the L servo control circuit 40, and also performs sequence control of the disk device by inputting recalibrate (re-initialization) and seek commands from the interface circuit 60. Further, by inputting temperature information measured before the start command is received from the TMC temperature measurement circuit 70, the spindle motor drive control according to the present invention is performed.

The SERVO-CTL servo control circuit 40 inputs positioning information read out from the disk medium 33 by the servo head 35, and performs servo control using the VCM 36.
A closed loop is configured by outputting the output to the interface circuit 60, which controls the positioning of the head on the cylinder and
The head movement control of the target cylinder address which is outputted from the CAR cylinder address register 50 and outputted onto the CA-BUS via the CAR cylinder address register 50 is performed under the instructions and supervision of the MPU microprocessor.

The TMC temperature measurement circuit 70 is supplied with power from the BATT battery power supply 80 and operates even when the device power is cut off. This circuit starts an interval timer and measures the temperature from the temperature sensor 71 every cycle t, and M+1 temperature data from the current time up to Mt ago are stored in the register.

Next, a spindle motor drive control method according to the present invention will be explained with reference to FIGS. 2, 3, 4, and 5.

FIG. 2 shows a part of the sequence of the FWM control memory circuit 20. First, the power is turned on (Power-on) 200.
When it detects that power is supplied by
01 and proceeds to start signal check 202. When a start command is received from the host controller,
Temperature measurement information reading 203 is executed. That is, M+1 temperature data measured by the TMC temperature measurement circuit 70 is input. Next, in temperature measurement information comparison 204, the input temperature data is compared with spindle motor drive conditions as shown in FIGS. 4 and 5. Here, it is compared whether the input M+1 temperature data is within the motor drive permission range corresponding to each time, and if it is outside the range, the contents of the temperature measurement result register (hereinafter abbreviated as TMR) is incremented. Next, when the contents of the temperature measurement result register are zero in the motor drive check 205, that is, all the input temperature data is within the motor drive permission range, the spindle motor drive sequence 206 is executed, and the recalibrate seek 207 is performed.
After that, it becomes ready state 208. If even one piece of temperature data exists outside the motor drive permission range, the motor is not driven, the TMR is cleared, the process returns to the temperature measurement information reading 203, and the temperature data is compared in the motor drive check 205 until the TMR becomes zero. repeat.

FIG. 3 shows the sequence of the temperature measurement circuit 70.
First, connect the battery power source 80 (Power-on) 2
10 detects that power is supplied, initialization 211 is executed, and timer start 212 starts an interval timer with period t. When the timer is set in timer set check 213, the process proceeds to temperature measurement 214. In temperature measurement 214, the temperature inside the HDA is measured by the temperature sensor 71. Next, in the temperature measurement information update 215, the current temperature data and the temperature data measured t to Mt ago are stored in the registers corresponding to the respective times, and the process returns to the timer start 212, where the temperature measurement and temperature data are updated every time t. Perform updates.

FIG. 4 is an example of comparing temperature information and spindle motor drive conditions when the power is turned on at T=TM. In this case, the temperature data (black dots) at T=TN-2 to TN+3 is outside the motor drive permission range, so the value of the temperature measurement result register (TMR) is 5, so the spindle motor remains stopped. It is.

Next, T=TM+4=TM+4t in FIG.
When the power is turned on, all the temperature data is within the motor drive permission range, so the TMR value becomes zero and the spindle motor starts to drive.

[0015]

As explained above, the present invention uses a temperature measurement circuit that measures the temperature inside the HDA and a battery that supplies power to the temperature measurement circuit to drive the spindle motor in response to a start command after the device is powered on. Before starting, the temperature information before the start command is received from the temperature measurement circuit is input and compared with the motor drive conditions, and by adding a function to judge whether to start motor drive, the temperature inside the HDA and the temperature of the disk medium/head can be checked. Since the spindle motor is driven only when the temperature is within the safe range, it has the effect of reducing device failures and malfunctions due to temperature abnormalities after the power is turned on.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a flowchart showing part of the control of the FWM control memory circuit of FIG. 1;

FIG. 3 is a flowchart showing control of the temperature measurement circuit of FIG. 1;

FIG. 4 is a diagram showing the relationship between temperature measurement information and motor drive conditions.

FIG. 5 is a diagram showing the relationship between temperature measurement information and motor drive conditions.

Claims (3)

[Claims] 1. A head disk assembly comprising a disk medium, a data head disposed on the disk medium, fixed to each other and positioned by a head positioner, and a spindle motor for controlling rotational movement of the disk medium; In a magnetic disk drive that includes a temperature measurement circuit that measures the temperature inside the head disk assembly and a battery that supplies power to the temperature measurement circuit, the temperature measurement circuit starts the operation after the power is turned on and before the spindle motor starts driving according to a start command. Input the temperature information before the command and compare it with the motor drive conditions,
A spindle motor drive control method for a magnetic disk device, characterized by a function of executing a motor drive operation if temperature information satisfies a drive condition. 2. The spindle motor drive control method according to claim 1, wherein the spindle motor drive comprises the following process: (A) A process of inputting current and past head disk assembly internal temperature information from a temperature measurement circuit. (B) Process of comparing input temperature information with motor drive conditions. (C) A process of determining whether to execute or suspend motor drive as a result of the comparison made in section (B). 3. An interval timer, a register for inputting temperature data measured by a temperature measurement element every time the timer is set, and past temperature data (temperature information).
a temperature measurement circuit comprising a register in which temperature information is stored and the temperature information is updated each time temperature measurement is performed, a battery that supplies power to the temperature measurement circuit, and a register that stores temperature information input from the temperature measurement circuit. , a memory that stores data for comparing temperature information, a register that stores the comparison results, and a selector that selects whether to proceed to motor drive execution processing or return to temperature comparison processing depending on the register value. 1. A spindle motor drive control mechanism for a magnetic disk device, comprising a microprocessor circuit configured as shown in FIG.