JP2001330446A - Automobile navigation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a user to operate after a start-up process without keeping the user waiting by greatly shortening the start-up process necessary for displaying the present position at a start time or the like. SOLUTION: The automobile navigation system 1 displays the present position and guides routes to support running of a vehicle with the use of map data recorded in a CD-ROM 2. In the start-up process of turning off a power source with the same CD-ROM 2 kept loaded and turning on the power source again, the present position displayed last is displayed with the use of data held in an SDRAM 5 backed up by a battery and the user's operation to an input unit 13 is accepted with priority. Even when the same CD-ROM 2 is taken out once and inserted again or when a music CD is inserted again after being reproduced, the start-up process can be shortened with the use of the backed up data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a navigation apparatus which reads map data recorded on an exchangeable recording medium and displays a current position and a map for route guidance.

[0002]

2. Description of the Related Art Conventionally, a navigation device mounted on a vehicle such as an automobile to provide driving assistance displays a current position and a map for route guidance. Map data required for map display is on CD-ROM (Compact Dimm
sc-Read Only Memory and DVD-ROM (Digital Ve
It is pre-recorded and supplied to a large-capacity recording medium such as a rsatile disc-read only memory. The map data has a data structure that is hierarchized in a plurality of stages. The lower hierarchy contains detailed information for each relatively narrow range, and the upper hierarchy contains main information for each relatively wide range. included. The navigation device also detects the current position as a premise for displaying the current position and displaying a map for route guidance.
The current position is detected by GPS (Global Positioning System).
m), autonomous navigation, etc., and correction by map matching so that the vehicle is located on the road.
Since map data is also required for map matching, map data for map matching is read separately from that for map display. Reading of map data from a recording medium is frequently performed at the time of startup or when the recording medium is replaced.

Japanese Patent Laid-Open Publication No. Hei 10-239073 discloses that predetermined information for map display is stored in a non-volatile storage means immediately before the power is turned off, and is stored in the non-volatile storage means when the power is turned on. There is disclosed a prior art for reading information stored and performing map display.

[0004]

In a conventional on-vehicle navigation device, after power-on, TOC (Table Of Contents) information, disk identification information, disk information management information, and map display are obtained from a map recording medium such as a CD-ROM. Various kinds of parameter data, scale management information, map data to be displayed, and the like are read, and map drawing and display processing is performed. For this reason, it takes, for example, ten to several seconds until a map to be displayed such as around the current position is displayed.
It takes a considerable amount of time of several tens of seconds, during which time the user's operation is not accepted, and even if the user needs to scroll or to switch the scale to confirm the position on the map,
The result is to make the user wait.

In the prior art disclosed in Japanese Patent Application Laid-Open No. 10-239073, a simple map display is performed without reading from a map recording medium when the power is turned on, and the display waiting time is reduced. However, a user operation is accepted until other processes necessary for operating as a navigation device from the map recording medium, for example, a process of reading necessary data from the map recording medium in search processing, search processing, guidance processing, and the like are completed. Can not do.

In the map display, data of a display image at the time of power-off is stored in a non-volatile storage means. Therefore, when a map display different from the current position display is being performed, the map display immediately before the power-off is performed. The content will be reproduced.
In such a case, even if the driver of the vehicle is most likely to need to display the current position, it takes a relatively long time until the current position can be displayed, as in the case of conventional startup. have to wait. The driver of the vehicle
In some cases, it is necessary to start the vehicle immediately after starting the engine, and in such a case, the current position display cannot be made to correspond.

Further, in FIG. 7 and the like, if there is a possibility that a disk as a map recording medium can be exchanged in the CD-ROM driver unit, a process of accessing the disk, reading out drawing parameters and the like and storing it in the nonvolatile memory is performed. It is described that it will be performed. The judgment in the CD-ROM driver section should be the presence or absence of the attachment / detachment of the disk. Even if the disk once taken out is mounted again, it should be judged that the disk is replaced.
Therefore, even if the same disk is mounted without actually replacing the disk, once the disk is removed, the disk is accessed and the same startup time as in the case of disk replacement is required. I will.

[0008] It is an object of the present invention to provide a navigation device that can greatly shorten the startup processing required for displaying the current position at the time of startup or the like.

It is another object of the present invention to provide a navigation device that enables a user operation after a start-up process without waiting.

[0010]

According to the present invention, there is provided a navigation device which reads map data recorded on an exchangeable recording medium and displays a map for present position display and route guidance. According to the program,
Processing means for performing processing necessary for map display, and a memory used for processing of map display by the processing means and having a backup area in which at least a part of the storage area retains stored contents even after the operation is stopped. Wherein the processing means performs a process for displaying a map using the backup area, and performs a map display for displaying a current position based on the storage content of the backup area at the time of startup. Navigation device.

According to the present invention, the processing means included in the navigation device reads the map data recorded on the exchangeable recording medium according to a preset program, and displays the current position and the route guidance. Performs processing required for map display. The memory is used for processing the map display by the processing means, and has a backup area in at least a part of the storage area where the stored contents are retained even after the operation is stopped. The processing means performs a process for displaying a map using the backup area, and displays a map for displaying the current position based on the stored contents of the backup area at the time of startup. At startup, the map display for displaying the current position is performed based on the stored contents of the backup area of the memory, and there is no need to read map data from the recording medium. Can be shortened.

Further, in the present invention, the processing means stores identification information of a recording medium holding the map data in a backup area of the memory, and when the recording medium is removed, only the identification information is stored. Is performed to invalidate.

According to the present invention, the identification information of the recording medium is held in the backup area of the memory, and when the recording medium is removed, only the identification information is invalidated. When a new recording medium is inserted due to invalidation of the identification information, the identification information is read out and compared with the invalidated identification information held in the backup area to determine the identity of the recording medium. Can be. If the same recording medium is used, other information is held in the backup area, so that it is not necessary to newly read the information, and the time required for the start-up processing can be reduced.

In the present invention, the processing means reads the identification information from the recording medium when the recording medium is inserted when the identification information held in the backup area of the memory is invalid, and When it is determined from the identification information that the map data is not recorded on the recording medium, the storage contents of the backup area are retained.

According to the present invention, even when the recording medium on which the map data is recorded is removed and the identification information held in the backup area of the memory becomes invalid, the recording medium on which the map data is not recorded is stored. Is inserted,
Since the storage contents of the backup area are retained, when the original recording medium recording the map data is reinserted,
Using the stored contents, the time required for the start-up process can be reduced.

Further, in the present invention, the processing means determines whether or not the storage content of the backup area of the memory is damaged, discards the storage content of the backup area, restarts by a soft reset process, Data necessary for display is read again from the recording medium.

According to the present invention, there is no need to attach or detach a recording medium,
Even if a map display for displaying the current position is possible using the stored contents held in the backup area of the memory, if the stored contents are broken, the stored contents of the backup area are discarded, and the software reset processing is performed. Since the data is restarted and the data necessary for the map display is read again from the recording medium, an abnormal operation such as repeating the software reset process in the map display based on the corrupted storage contents can be avoided.

Further, in the present invention, the processing means displays a map based on the storage contents of the backup area at the time of starting, and then performs processing in accordance with a predetermined priority order which prioritizes a user operation. And

According to the present invention, after the map is displayed based on the storage contents of the backup area of the memory, the processing is performed in accordance with a predetermined priority order that prioritizes the user operation, so that the user operation after the start-up processing is made to wait. Can be made possible without.

Further, in the present invention, the processing means divides the backup area of the memory into a map display area and a map matching area for correcting a current position on a road.
At least the map data used for the latest processing is stored.

According to the present invention, the map data used for the latest processing is stored in the backup area of the memory separately for map display and map matching. Can be done quickly.

Further, in the present invention, the storage content of the backup area of the memory includes information indicating a display scale used for displaying the latest current position, and the processing means is configured to display the map scale after the start-up. Then, it is determined whether or not map display on the display scale is possible using the map data held in the backup area, and if it is determined that the map display is possible, map display on the display scale is performed. When it is determined that, the map is displayed using the map data for the map matching, and then the map data for performing the map display on the display scale is read from the recording medium to perform the map display. And

According to the present invention, in the backup area of the memory, information indicating the display scale used for displaying the latest current position is held, and if it is possible using the map data held in the backup area, The map is displayed on the display scale, and if not possible, the map is displayed using map data for map matching, and then the map data for displaying the map on the display scale is read from the recording medium. Since the map is displayed, the time required for starting up until the current position can be displayed can be reduced. Even when the vehicle starts running immediately after the start, the current position is displayed, so that the current position can be prevented from being lost.

In the present invention, the map data for map matching can be displayed on a plurality of display scales.
The processing unit is not capable of displaying a map on the display scale, and when displaying a map using the map data for map matching, performs a map display on a scale closest to the display scale. I do.

According to the present invention, the map is displayed on the scale closest to the display scale of the original current position display using the map data for map matching, so that the vehicle starts running immediately after starting. However, the map can be displayed quickly and easily.

In the present invention, the processing means cannot display a map on the display scale, and displays a map using the map data for the map matching and, when a user operation is performed, displays the map. A process for reading map data for displaying a map on a scale from the recording medium is interrupted, and a process corresponding to the user operation is performed.

According to the present invention, when the display scale is different from the original map display in the map display for displaying the current position at the time of activation, the user operation is performed while performing processing for adjusting to the original map display. Acceptance can be made so that the user operation after the start-up processing can be accepted without waiting.

[0028]

FIG. 1 shows a basic hardware configuration of a navigation apparatus 1 according to an embodiment of the present invention. The navigation device 1 according to the present embodiment is mounted on a vehicle and uses a map data recorded on a CD-ROM 2 that is a map recording medium to display a current position and provide various kinds of guidance for driving assistance. The CD-ROM 2 is detachable, and stores not only map data but also image data serving as parts for various guidance displays, guidance information on tourist spots, voice phrases for voice guidance, and the like. Further, not only the CD-ROM 2 for map display but also a CD for music reproduction can be used. When a CD for music reproduction is inserted, the operation as the navigation device 1 is temporarily stopped, and the music reproduction operation is performed. I do. In addition,
The present invention can be similarly applied to a case where another recording medium such as a DVD-ROM is used as a map recording medium. In the following description, a map recording medium such as the CD-ROM 2 may be simply referred to as a “disk” for simplification of the description.

The operation of the navigation device 1 is C
This is performed by a PU (Central Processing Unit) 3 controlling each unit according to a program stored in the ROM 4 in advance. The CPU 3 serving as a processing unit is an SDRAM (Synchronous Dynamic Rand) as a main memory.
om Access Memory) 5 to perform a program operation. The SDRAM 5 is backed up by the power supply voltage + B from the vehicle battery even when the power switch (SW) as the navigation device 1 is in the OFF state, and the refresh operation for retaining the stored contents is also performed. The CPU 3, the ROM 4, and the SDRAM 5 constitute a control device 6.

The driving assistance for the driver of the vehicle as the navigation device 1 includes a graphic controller 7 for displaying images, a graphic memory 8, a display controller 9, a display device 10, and a voice output device 11 for voice guidance. This is performed by the output device 12. The graphic controller 7 draws an image for image display in the graphic memory 8, transfers the image data to the display controller 9, and causes the display device 10 to display the image. The image for display is composed of multiple layers,
The display controller 9 performs sprite processing for superposition and the like. The display device 10 is formed by a color liquid crystal display panel or the like, and displays an image for driving assistance. The voice output device 11 performs voice guidance at an intersection or the like by combining voice phrases recorded on the CD-ROM 2.

A user of the navigation device 1 such as a driver or a passenger of the vehicle uses the input device 13 to perform a user operation for selecting an operation mode and a function, and for instructing scrolling of display and changing of scale. Can be. The input device 13 includes a function key, a joystick, a remote control device, and the like arranged around the display screen of the display device 10. The input device 13, the output device 11, and the control device 6 are connected via a system bus 14, and transfer data and control signals.

The system bus 14 is connected to the interface 1
5, a direction sensor 16, an angular velocity sensor 17, a distance sensor 18, and a GPS (Global Positioning System).
) It is also connected to the device 19 and the like. The direction sensor 16
A geomagnetic sensor or the like can be used, and the direction of the vehicle is absolutely detected based on the geomagnetism. Angular velocity sensor 17
Can use a vibration gyro or the like, and relatively detect a change in the traveling direction of the vehicle. The distance sensor 18 detects a traveling distance of the vehicle. If the change in the traveling direction is detected by the direction sensor 16 or the angular velocity sensor 17 while the vehicle is traveling, and the traveling distance is detected by the distance sensor 18, the current position of the vehicle with respect to the traveling start point is obtained by autonomous navigation. be able to. The absolute current position of the vehicle is G
It can be determined by the PS device 19. Control device 6
Performs a process of inputting output data from each sensor and the GPS device 19 via the interface 15 and obtaining a current position. Map matching for correcting the obtained current position on the road is also performed.

The reading of various data from the CD-ROM 2 is performed via a CD-ROM driver 20 and a CD-ROM decoder 21. CD-ROM driver 20
Has a removable CD-ROM 2 and a CD-ROM 2
When the camera 2 is mounted, it can be rotated to optically read recorded contents. CD-ROM decoder 21
Converts the format of the output data from the CD-ROM driver 20 into a format that can be easily handled by the control device 6. This is because data actually recorded on the CD-ROM 2 is subjected to various types of processing in order to enhance reliability, and it is difficult to handle the data by the processing device 6 as it is.

By operating an ignition switch of a vehicle on which the navigation device 1 is mounted, for example, starting an engine.
ACC (Accessory) If you keep the position above the power supply, A
The CC power-on is detected by the detection circuit 22 and the start-up operation is started. The power supply voltage is supplied from a battery or a generator of the vehicle. A voltage is directly supplied from the battery as a + B voltage via a power switch (SW), and is detected by the detection circuit 22. The voltage from the ACC power supply or the battery power supply is converted into a constant voltage by the regulator 23 and supplied to each unit. The detection circuit 22 also detects the operation state of the illumination switch related to the illumination of the vehicle, and uses it for controlling the brightness of the display of the display device 10 and the like.

FIG. 2 shows a data structure of information and data recorded on the CD-ROM 2 as a map recording medium. Is recorded on the innermost side of the CD-ROM 2. The disc identification information of each CD-
In addition to making the ROM 2 individually identifiable, the ROM 2 also includes information such as whether it is a map recording medium, a music CD or a game CD-ROM. The data management information in the disk is management information of what data is recorded in which position as the map recording medium. Are various data of colors and marks necessary for drawing a map. The scale management information is information on a map scale and a display scale. Is a road map represented by a combination of coordinates and vectors, and is used for road marking and map matching. The guidance system data includes a voice phrase for voice guidance at an intersection or the like. The search system data is road network information that can determine the route cost used for the route search. The road is represented by a combination of a link and a node. For the link, the road type, road width, length, direction, etc. Including.
For a node, if it is an intersection, its name, connection link, traffic regulation information, etc. are included. Is data that can be searched for by Japanese syllabary or by telephone number.

The CPU 3 of the present embodiment converts the information and data of
Back up to M5. Of these, and are treated as “resident data A”, and are treated as “resident data B”.
These data are read only when the system is first started, and thereafter, as long as the same disk is used,
It keeps holding it backed up in RAM5.
Map data is treated as “non-resident data”, and the CD-display area changes as the map display area changes due to user operation or the like.
The data is read from the ROM 2 and stored in the SDRAM 5. Since the memory area that can be held is limited, if there is no room to newly hold map data, the oldest data is discarded, and the new data is held.

FIG. 3 shows a processing procedure after activation in the navigation device 1 of the present embodiment. The procedure is started from step a1, and in step a2, the power switch is turned on. At this time, the activation flag is set to 1.
At step a3, it is determined whether or not the activation flag is set to "1". If the activation flag is not 1, step a
In step 4, the data backed up in the SDRAM 5 is discarded. Start the procedure from step a1, and
When the power is turned on in step 2, the backup flag is 1, and the backup data is not discarded. When it is determined in step a3 that the activation flag is 1, or after the backup data is discarded in step a4, it is determined in step a5 whether or not there is a disk.
If there is no disc, the process waits for insertion of a disc in step a6, and if inserted, returns to step a5.

If it is determined in step a5 that there is a disk, it is determined in step a7 whether the resident data A is in the backup area of the SDRAM 5. If it is determined that the resident data A including the TOC and the disc identification information does not exist, the resident data A is copied to the CD-R in step a8.
Read from OM2. When it is determined in step a7 that there is resident data A, or in step a8,
Is read, in step a9, it is determined based on the disc identification information whether or not the disc is a map disc on which map data is recorded.

If it is determined in step a9 that the disk is a map disk, it is determined in step a10 whether the disk is the same disk as the previous disk. Whether or not the disks are the same can be determined based on the identification information of the resident data A. As will be described later, once the disc is ejected, the resident data A is invalidated. Even if the resident data A becomes invalid, main information is held together with information indicating that it is invalid. Therefore, even when the resident data A is read in step a8, the read resident data A can be compared with the held invalid resident data A to determine the disc identity. . Step a1
If it is determined at 0 that the disks are the same, it is determined at step a11 whether or not there is resident data B. When it is determined in step a10 that they are not the same disk, and when it is determined that there is no resident data B in step a11,
In step a12, the resident data B is read from the disk,
The data is stored in a predetermined memory area of the SDRAM 5. The resident data A is also stored.

When it is determined in step a11 that the resident data B is present, or after the resident data B is read in step a12, the last map is displayed in step a13. Details of the last map display will be described later with reference to FIG. In the last map display, the last map for which the current position was displayed before the activation is displayed. If the same disk as the previous one is used, step a8 or step a1
Since the resident data A and B can be displayed without reading them, the time required for the start-up process can be reduced. When the map data used for the last map display is backed up, the time can be further greatly reduced. Even when the disk once ejected is inserted again, only the process of reading the resident data A in step a8 needs to be performed on the disk, so that the time required for the start-up process can be reduced.

At step a14, other data necessary for normal processing as the navigation device 1, for example, the data shown in FIG. However, if a user operation is performed on the input device 13 before the reading process is completed, the user operation is preferentially accepted. As a result, a map display of the current position display can be quickly performed after the navigation device 1 is started, and the time required until a user operation can be received can be significantly reduced. If the user operation is performed, the process is performed according to the content, and the process proceeds to the navigation normal process of step a15. Even when the data reading process is completed before the user operation is performed in step a14, the process proceeds to the navigation normal process in step a15. In the normal navigation process, processes such as a current position display, a route search, and route guidance as the navigation device 1 are performed according to a user operation. However, the processing of current position detection and map matching is always performed as background processing. Step a17 as part of the normal navigation process
It is determined whether or not the disc has been ejected.

If it is determined in step a9 that the disc is not a map disc, reproduction processing as a music disc is performed in step a16. When a video or game disk, which is neither a map disk nor a music disk, is inserted, an error is notified using the display device 10 and the audio output device 11. The backup data as the navigation device 1 is retained without being discarded. When the reproduction process ends, the process moves to step a17.

In step a17, it is determined based on a signal from the CD-ROM driver 20 whether or not the disk has been ejected. If it is determined that the disc has been ejected, the process proceeds to step a18, and processing for invalidating the resident data A is performed. The invalidation process is performed by adding data such as a flag indicating invalidity to a part of the resident data A, and the main part of the resident data A is held. Resident data B and map data are not discarded but are left as they are. Next, in step a19, it is determined whether the power is off. Power supply is O
If it is not FF, the process returns to step a6 and waits for insertion of a disk. If it is determined in step a17 that the disc has not been ejected, the power is turned off in step a20.
It is determined whether or not it is. If the power is not off, it is determined in step a21 whether or not the disc is a map disc. If it is a map disc, return to step a15,
Continue normal navigation processing. If it is determined in step a21 that the disc is not a map disc, the process returns to step a16. If it is determined in step a19 or step a20 that the power is OFF, the procedure ends in step a22.

FIG. 4 shows a processing procedure for displaying the last map in step a13 of FIG. The procedure starts from step b1, and in step b2, a map at the last current position is specified. For example, the map used for displaying the current position until the vehicle is parked is the map of the last current position. If the power is turned off after parking and the power is turned on and the navigation device 1 is started, the last current position is displayed. The map data should remain in the SDRAM 5. If other operations for displaying the current position are performed before the power is turned off, there is a possibility that the map data of the last current position does not remain. In step b3, it is determined whether there is map data at the last current position. If it is determined that there is no
At step b4, map data of the current position is read. When it is determined in step b3 that there is map data of the last current position, or after reading has been performed in step b4, a map of the current position is drawn in step b5, and it is determined whether or not the map was normally drawn in step b6. to decide. If an abnormality has occurred in the map data, an error is detected based on the error detection information, a data range is out of a predetermined range, or an error detection condition of the CPU 3 is satisfied, and a soft reset occurs. . As a soft reset process, in step b7, the activation flag is reset to 0, and the process returns to step a3 in FIG. As described above, if the activation flag is not 1, the backup data is discarded in step a4, so that new data is read from the disk, and the data abnormality can be resolved. Therefore, even if a soft reset once occurs due to a data abnormality, the data abnormality does not occur continuously, and repetition of the soft reset can be avoided.

If it is determined in step b6 that the map of the current position has been normally drawn, the map of the current position is displayed on the display screen of the display device 10 in step b8, and the procedure ends in step b9.

FIG. 5 shows the hierarchical structure of map data recorded as map data on the CD-ROM 2. The map data is recorded in a plurality of stages from the lowest scale level 0. The lower the scale level, the narrower the geographical area to be targeted, and the more detailed information is included. Therefore, the number of lower map data is larger than the number of higher map data. The map data of the higher scale level is used for grasping the outline of the route and the current position.

FIG. 6 shows the registration state of the read map registration area of the SDRAM 5. In the present embodiment, the same map data is backed up separately for map matching and map display. The numerical value before "-" corresponds to the scale level shown in FIG. The map data read by the map matching processing performed in accordance with the movement of the vehicle in the course of the navigation normal processing in step a15 in FIG. 3 is used for map matching.
Map data read by map display processing such as current position display, map scrolling, and scale switching are registered in a map registration area of the SDRAM 5 for map display. However, since the size of the map registration area is finite,
It is not possible to register all map data and replace old map data with new map data that needs to be accessed, so the last map data used for current location display is the map registration area for map display. May not be registered.

FIG. 7 shows an example of a map display for displaying the current position. In the map display, a display scale 30 is displayed somewhere on the display screen. The display scale is managed as scale management information of the resident data B. When the display scale of the last current position display corresponds to the scale level 0, the backup data for map display shown in FIG.
Although there is no corresponding map data, the current position can be displayed using map data for map matching. The map matching is always performed as a background process even when the current position is not displayed, and the map data covering the latest current position should be held.

If the display scale of the current position of the last is different from the display scale that can be displayed by the map data for map matching, the map is first displayed using the map data for map matching, and then the map is displayed. Is read and displayed on the map data of the current position display scale.
That is, in FIG. 7, when the display scale of the last current position display is the scale level 2, although there is no backup data that can be displayed, the map is displayed using the backup data for map matching at the scale level 0,
Thereafter, the map data of the scale level 2 is read to replace the map display.

During the process of reading the map data of the scale level 2, for example, when the scale is switched by a user operation, and it becomes necessary to read the map data of the scale level 3, the scale level 2 is read. Reading of the map data is interrupted, and the map data at the scale level 3 is read.

FIG. 8 shows a priority order in the reading order control for giving priority to such a user operation. The highest priority request having a read request priority of 0 is assigned to voice data for guidance. This is because voice data needs to be generated at an appropriate timing at a guide point such as an intersection. Next, a request accompanying a user operation having a reading request priority of 1 is assigned to scrolling, scale switching, point map display, and the like. Image data for route guidance and highway map data are assigned as a prefetch request in which the timing of the next read request priority 2 is important. As the pre-reading request of the reading request priority 3, map data and the like necessary for scrolling to display the current position of the vehicle centering on the own vehicle position are assigned. At the read request priority 4, as a request that can be “waited” at a constant interval, map data for map matching or the like is assigned. Data and the like used for the route search are assigned to the read request priority 5 having the lowest priority. The route search is usually performed while other processing is not being performed, such as before the vehicle starts running, so that the priority can be kept low.

Read requests to the disk are queued when contention occurs. If a request having a different priority is already registered in the queue, the request to be newly registered is registered at a higher rank if it has priority, and is registered at a lower rank if it is subordinate. When requests having the same priority conflict, the requests are registered in a queue in the order in which the requests are received. However, the read request priorities 4 and 5 are variable priorities. After the request of the variable type priority is registered in the queue, if the processing for the request registered in the queue is performed, the priority is advanced by one stage only once.
That is, the priorities 4, 5 are advanced to 3, 4, respectively.

As another embodiment of the present invention, when a map for displaying the current position is displayed using the map data for map matching as described above, the map is displayed on a display scale close to the last current position display. You can also do so.
The map data used in the navigation device 1 corresponds to a plurality of display scales at one scale level. For example, at scale level 0, 50m, 100m, 200m
When the last display scale of the current position is 800 m, the nearest 2
00m is selected and a map is displayed.

Although the SDRAM 5 in FIG. 1 is entirely backed up, a partial backup may be used as long as there is a capacity necessary for holding backup data. The type of memory element is not limited to SDRAM,
Any other type of memory, such as an SRAM (Static RAM), that always backs up data, may be used.

[0055]

As described above, according to the present invention, at the time of startup, a map display for displaying the current position is performed based on the contents stored in the backup area of the memory, and it is not necessary to read the map data from the recording medium. Since there is no start-up time, the start-up time required for displaying the current position can be greatly reduced.

According to the invention, the identification information of the recording medium is held in the backup area of the memory, and when the recording medium is removed, only the identification information is invalidated.
When the same recording medium is inserted again, other information of the identification information is held in the backup area, so that it is not necessary to newly read the information and the time required for the start-up processing can be reduced.

According to the present invention, after the recording medium on which the map data is recorded is replaced with a recording medium on which the map data is not recorded, the original recording medium on which the map data is recorded is reinserted. When this is done, the time required for the startup process can be reduced.

Further, according to the present invention, when the storage contents held in the backup area of the memory are broken,
Since the stored contents of the backup area are discarded, restarted by the soft reset process, and the data necessary for the map display are read from the recording medium, an abnormal operation such as repeating the soft reset process can be avoided.

According to the present invention, after the quick map display start-up processing, the processing is performed in accordance with a predetermined priority order in which the user operation is prioritized, so that the user operation can be accepted without waiting.

According to the present invention, the map data used for the latest processing is stored in the backup area of the memory separately for map display and map matching. Even at this time, it is possible to quickly correct the current position by map matching.

According to the present invention, if the current position can be displayed on the original display scale using the map data held in the backup area of the memory, the map display is performed on the display scale. Otherwise, the map is displayed using the map data for map matching, and then the map data for performing the map display at the display scale is read from the recording medium and the map is displayed, so that the current position can be displayed. The time required for starting up can be shortened. Even when the vehicle starts running immediately after the start, it is possible to keep track of the current position.

Further, according to the present invention, the map is displayed on the scale closest to the display scale of the original current position display using the map data for map matching, so that the current position display is performed in a state close to the original display scale. And the map display can be performed in an easily viewable state even when the vehicle starts running immediately after the start.

Further, according to the present invention, when the map is displayed on the display scale for displaying the current position at the time of startup and the display scale is different from the original map display, the map for adjusting the display scale to the original map display is displayed. While reading data,
User operations can also be accepted and can be accepted without waiting for user operations.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic hardware configuration of a navigation device 1 as one embodiment of the present invention.

FIG. 2 is a diagram showing a data structure of information and data recorded on a CD-ROM 2 of FIG. 1 as a map recording medium.

FIG. 3 is a flowchart showing a processing procedure after activation in the navigation device 1 of FIG. 1;

FIG. 4 is a flowchart showing a processing procedure for displaying a last map in step a13 of FIG. 3;

FIG. 5 is a diagram showing a hierarchical structure of map data recorded as map data on the CD-ROM 2 of FIG. 1;

FIG. 6 is a diagram showing a registration state of a read map registration area of the SDRAM 5 of FIG. 1;

FIG. 7 is a diagram showing an example of a map display for displaying a current position in the embodiment of FIG. 1;

FIG. 8 is a table showing priorities in reading order control for giving priority to a user operation in the embodiment of FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 navigation device 2 CD-ROM 3 CPU 4 ROM 5 SDRAM 10 display device 11 audio output device 13 input device 20 CD-ROM driver 30 display scale

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C032 HB02 HB05 HB22 HC01 HC08 HC13 HC15 HC24 HC25 HC31 HD03 HD30 2F029 AA02 AB01 AB07 AC02 AC06 AC14 AC18 AC20 AD01 5H180 AA01 BB13 CC12 FF04 FF05 FF10 FF22 FF25 FF27 FF27

Claims (9)

[Claims] 1. A navigation device which reads map data recorded on an exchangeable recording medium and displays a map for present position display and route guidance. Processing means for performing processing, and a memory used for processing of map display by the processing means and having a backup area in at least a part of the storage area, the storage content of which is retained even after the operation is stopped; A navigation device that performs a process for displaying a map by using the backup area, and performs a map display for displaying a current position based on the stored contents of the backup area at the time of startup. 2. The processing means stores identification information of a recording medium on which the map data is recorded in a backup area of the memory, and invalidates only the identification information when the recording medium is removed. The navigation device according to claim 1, wherein the navigation device performs a process of performing the following. 3. When the identification information held in the backup area of the memory is invalid, the processing means reads the identification information from the recording medium when the recording medium is inserted, and reads the identification information from the identification information. 3. The navigation device according to claim 2, wherein when it is determined that the map data is not recorded on the recording medium, the storage content of the backup area is retained. 4. The processing means determines whether or not the storage contents of a backup area of the memory are damaged, discards the storage contents of the backup area, restarts by a soft reset process, and is necessary for map display. The navigation device according to any one of claims 1 to 3, wherein necessary data is read again from a recording medium. 5. The processing unit according to claim 1, wherein at the time of starting, after displaying a map based on the storage contents of the backup area, the processing unit performs processing in accordance with a predetermined priority order that prioritizes a user operation. Item 5. The navigation device according to any one of Items 1 to 4. 6. The processing means separates a backup area of the memory into a map display area and a map matching area for correcting a current position on a road. The navigation device according to claim 1, wherein the navigation device stores data. 7. The storage content of the backup area of the memory includes information indicating a display scale used for displaying the latest current position, and the processing unit performs the processing when displaying the map after the startup. Using the map data held in the backup area to determine whether or not a map display on the display scale is possible, when it is determined to be possible, perform a map display on the display scale,
When it is determined that it is not possible, a map is displayed using the map data for the map matching, and thereafter, the map data for performing the map display on the display scale is read from the recording medium to perform the map display. 7. The navigation device according to claim 6, wherein: 8. The map data for map matching can be displayed on a plurality of display scales, and the processing means cannot display the map on the display scale and uses the map data for map matching. 8. The navigation apparatus according to claim 7, wherein when displaying the map by using a map, the map is displayed on a scale closest to the display scale. 9. The processing means cannot display a map on the display scale, and when a user operation is performed after displaying a map using the map data for map matching, the processing means displays the map on the display scale. 8. The method according to claim 7, wherein a process for reading map data for displaying a map from the recording medium is interrupted and a process corresponding to the user operation is performed.
Or the navigation device according to 8.