JPH0378838A - Information processor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides an information processing device that eliminates the instability of electronic equipment.

[Prior Art] Conventionally, electronic devices have been in an unstable state, for example, due to internal software processing not operating normally, for example, a runaway phenomenon has occurred.
The equipment may become completely inoperable. When turning off electronic equipment, there is a hardware method of turning off the device's power switch and directly cutting off the power line. Resetting is generally practiced. On the other hand, as a software method, a method called a non-maskable interrupt, ie, rNMIJ, has been used by detecting that the main switch is turned off.

FIG. 4(a) shows an example of the circuit configuration of a power supply control circuit according to the prior art, in which the main switch human power signal 401 and the battery voltage are low when the power supply on/off control signal is below a certain level. A signal, that is, a power fail signal 402 is used, and the power is turned on when the power control signal 40B becomes high. The power is turned on when both the main switch input signal 401 and the power fail signal become high, and when the power switch input signal or the power fail signal becomes low, an NMI signal 407 is generated and the power off command 403 is issued by software. Turn off the main power.

In addition, if the software is running out of control or the NMI signal does not work, turn off the main switch 401 and press the reset button to send the reset signal 401.
It is known that the main power supply is turned off by a hardware method of turning off the main power supply.

FIG. 4(b) is the timing chart of FIG. 4(a),
Main switch signal 401 and power fail signal 4
The power supply control signal 406 becomes high at tl when both 02 and 02 become high. At t3, the main switch is turned off and NM
The r signal 407 is generated, causing the software to generate a power-off command 403, which causes the power control signal 4 to be generated.
By setting 06 low, the main power is turned off. t
3 is a case where the power fail signal is turned off, and the main power is turned off in the same way as when the main switch is turned off. In FIGS. 4(a) and 4(b), the same numbers mean the same things.

[Problem to be Solved by the Invention] However, in the above-mentioned conventional technology, when the main power is turned off by hardware, there is a problem that the memory contents are destroyed if the power is turned off while accessing the RAM, external storage device, etc. There is. Furthermore, in small information processing devices, liquid crystals are used in the display section, and the order in which the voltages are turned on and off is determined for the different types of voltages used in these liquid crystals. If you turn off the power using hardware, this order will not be followed and there is a risk of damaging the LCD. Therefore, it is necessary to control the power off using software, but the conventional method of turning off the power using software has the problem that the power cannot be turned off when the software runs out of control or when interrupts are disabled by an application.

Therefore, the present invention is intended to solve these conventional problems.The purpose of the present invention is to use software to maintain the shutdown sequence of various power supplies such as LCD, even when the software runs out of control or when interrupts are disabled. An object of the present invention is to provide an information processing device that can reliably reset the unstable operating state of the device and bring the entire device into a stable state.

[Means for Solving the Problems] The present invention provides a power supply control circuit that automatically brings the device body to a stable state using software when the device body is in an uncontrollable unstable state. It is characterized by

[Function] According to the above configuration of the present invention, the power control circuit turns on and off the power in response to the main switch and the power fail signal, and the main switch is turned off or power fails when software runs out of control or interrupts are disabled. If the device is reset after a certain period of time, the device initial startup program (B I O
At the beginning of step 9), it is determined that the main switch is turned off or a power failure has occurred, and the main power of the device is turned off while observing the order in which various power sources in the device are turned off.

[Example 1] Fig. 1 is a block diagram of a power supply control unit according to the present invention, and an input signal 101 is a signal for determining whether to turn on or off the power supply, such as a main switch signal or a power fail signal, and is used to control the power supply control circuit and reset. It is input to the signal generation circuit, interrupt control means, and device initial startup means (BIO3). 102 is a power supply control circuit for sending a signal 103 to the power supply to actually turn on and off the main power supply; when the input signal 101 is high, the main power supply is turned on by setting the power supply control signal 10.3 to high; input signal 10
When 1 is low, an NMI signal 105 is generated. Also,
When the power-off command 104 is input, the main power is turned off by setting the power control signal 103 to low. Reference numeral 106 denotes an interrupt control means, which sends a power-off command 104 to the power supply control circuit 102 if the input signal 101 is low when an interrupt signal 107 is input from the CPU. 108 is a device initial startup means (BIOS)
), which normally starts the device from the initial state, but if the input signal 101 is low when the reset request signal 109 is input from the CPU, a power-off command 104 is sent to the power control circuit 102. It also has this function. 111 is a reset signal generation circuit, which generates a human input signal 10.
1 is low or when the reset button 110 is pressed, a reset signal 112 is sent to the CPU.

FIG. 2(a) shows an embodiment of the reset control circuit according to the present invention. 201 is the input signal from the reset button,
203 is a main switch signal, and 204 is a power fail signal. The reset button input signal 201 is low while the reset button is pressed, and the main switch signal 203 is low when the main switch is turned off.
Further, the power fail 1 word 204 becomes low when the battery voltage is below a certain level. The human power signal 202 is a signal that becomes low when the main power source is off and high when the main power source is on, and is a mask signal to enable the human power of the main switch signal 203 and power fail signal 204 only when the main power source is on. . Further, 207 is a circuit that outputs a reset signal that is at a low level for a certain period of time in synchronization with the rise of the input signal 205.

FIG. 2(b) is a timing chart of each signal in FIG. 2(a), and the circuit operation will be explained based on this diagram. t
18 output circuit 20
7 outputs a reset signal 206 in synchronization with the rising edge tl of the input signal 205. At t3, the power fail signal becomes low, thereby generating the reset request signal 205. The low level pulse width T1 at this time is the second
It depends on the time constant due to R and C in figure (a). A reset signal 206 is output in synchronization with the rising edge tl of this reset request signal 205. This operation is similar when a reset request signal is generated by the main switch signal 203.

Therefore, in the circuit of FIG. 2(a), instead of outputting a reset signal only when the reset button is pressed, the reset signal is output when the main switch manual signal 203 or the power fail signal 204 becomes low and a certain period of time elapses. 20
6 can be output automatically.

FIG. 3 is a timing chart from when the main switch (or power fail signal) 301 is turned off to when the power is turned off in the embodiment of the present invention. Figure 3(a) shows the case where the power is turned off by software due to an interrupt, and the processing required to turn off the power normally after turning off the main switch 301 with tl (processing to ensure that the order in which various power supplies are turned off is respected, etc.) This is done using software during T2 and the main power is turned off at t2. At this time, if the time T1 from when the main switch 301 is turned off until the reset signal 303 is generated is set to be longer than T2, the reset will not occur during the processing for turning off the main power supply. FIG. 3(b) shows a case where the software is running out of control or when interrupts are disabled. At this time, the power cannot be turned off by interrupts, so the reset signal 303 generated by the reset signal generation circuit is used to program the device's initial startup program. starts running. At the beginning of the program, the main switch level and power fail signal level are always monitored, and if the main switch is off or the power fail signal is low, the software will automatically turn off the various power supplies. Turn off the main power while observing the following order. Due to this function, the main power supply is turned off at t3.

[Effects of the Invention] As described above, according to the present invention, by adding a circuit and a program that can turn off the main power completely by software, it is possible to prevent the information processing device from running out of control and to prevent interrupts. The main power can also be turned off by software. Furthermore, since all power-off operations are performed by software, it is possible to use this software to maintain the order in which various power sources are turned off, and to save the contents of RAM before turning off the main power source. By taking into consideration the case where an unstable state occurs due to such a function, it is possible to improve the reliability of the information processing device.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a power supply control section of an information processing apparatus according to the present invention. FIG. 2(a) is an example of a reset signal generation circuit diagram in an embodiment of the present invention, and FIG. 2(l) is its timing chart. FIG. 3 is a timing chart when the main power R is turned off in the device of the present invention, FIG. 3(a) is a diagram when the main power is turned off by software during normal operation, and FIG. 3(b) is FIG. 6 is a diagram showing a case where the main power is turned off when software runs out of control or when interrupts are disabled. FIG. 4(a) is a diagram of an example of the circuit configuration of a power supply control circuit according to the prior art, and FIG. 4(1)) is a timing chart thereof. 101... Main switch signal or power fail signal 102... Power control circuit 103... Power control signal 104... Power off command 105... NMI signal 106... Interrupt control means 107... Interrupt Signal 108...Device initial startup means (BrO3) 109...
-Reset request signal 110...Reset button human power signal 111...Reset signal generation circuit 201...Reset button human power signal 202...Mask signal 203...Main switch signal 204...Power fail signal 205 ...Reset request signal 20G...Reset signal 20? ... Reset) [output circuit 301 ... Main switch signal (or power fail signal) 302 ... NMI signal 303 ... Reset signal 304 ... Power supply control signal 401 ... Main switch input signal 402 ... Power fail signal 403 ... Power off command 404 ... Reset signal 406 ... Power supply control signal 407 ... NMI signal or higher

Claims (1)

[Claims] An information processing device characterized in that the device main body is equipped with a power supply control circuit that automatically returns the device to a stable state using software when the device main body is in an uncontrollable unstable state.