JPS603050A - Initial program loading system - Google Patents

Abstract

PURPOSE:To read automatically control programs out of various external storage devices being object of IPL (initial program loading) by reading the kind of external storage device being object of IPL, and selecting properly a method of access to the external storage device. CONSTITUTION:A CPU1 and a floppy disk device 2 are connected through an address bus 3 and a data bus 4. The interface of the floppy disk device 2 consists of an address decoder 5 which decodes a device address outputted to an address bus 3 and an equipment kind encoder 7 which is activated by the output of the decoder 5 and outputs the equipment kind code characteristic to the floppy disk device 2. Then, the CPU1 detects the equipment kind of the floppy disk device 2 on the basis of the equipment kind code to perform proper IPL.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an initial program load (hereinafter referred to as IPL) method in a microcomputer system.

In the conventional technology, in a microcomputer system, a control program such as an OS is stored in an external RI++ storage device, and when the power is turned on, a program that executes IPL loads the control program into the main memory to start the system. is operating. A floppy disk device is a typical example of a storage device that stores the control program. Floppy disk devices have recording medium disks with a diameter of 8 inches, 5 inches, and even as small as 3 inches. In order to further increase capacity, devices with higher track density are also available. Therefore, Tlfi external storage devices that can be connected to microcomputer systems are prepared according to the user's purpose and preferences, allowing users to create various flexible system configurations. It's here. As a result, various types of external storage devices are connected to IPL, and each one has a different recording method, so the conventional uniform IPL power method cannot handle it. It's here.

In other words, in the conventional IPL method, the system configuration was determined and the external storage device to be subjected to IPL was also determined accordingly, but various Nowadays, it is necessary to be able to flexibly adapt the system configuration to suit the user's purpose and budget.

OBJECTS OF THE INVENTION One object of the present invention is to provide a program for executing IPL that can flexibly cope with computer system configurations that are diversifying depending on the type of program that executes IPL.

Another object of the present invention is that the program that executes IPL detects the type of external storage device that is the target of IPL, and selects and controls the basic access method to that device using j9. A flexible initial program loading method that performs an IPL operation suitable for the external storage device in which the program is stored and reads the control 311 program.
．． It's in a place where you can serve food.

Another object of the present invention is that the program that executes IPL does not fix the device address of the external storage device targeted for IPL, and also writes IPL to node IJj from a connected device of a different device 6 address.
An object of the present invention is to provide an initial program loading method that enables PL operations.

Embodiment Next, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment in which the CPU Kokyu detects the type of body storage device and executes an appropriate IPL, where ] is the CPU, 2 is a floppy disk device, and 3 is an address bus. , 4 is a data bus.

Furthermore, the interface of the floppy disk device fji 2 and the m configurations indicated by 1 to 1 are connected to an address decoder 5 which decodes the device address outputted to the address bus 3, and an output signal 6 of the decoder 5, so that 4=f Q'A This is a model encoder 7 which outputs a unique model code of the floppy disk drive R2. FIG. 2 is a circuit diagram showing an example of the model encoder 7. Here, 8-bit dip switches are used to generate 256 different model codes.

Each dip switch has contacts S that can be opened and closed in i+15 positions.
1 to S8, one of which is commonly grounded. The other contacts are individually biased with pull-up resistors R and connected to the input terminals of open collector type OR cables G1 to G8.

When the other input terminal of the OR gates G1 to G8 is activated by the output signal 6 (LOW level) of the address decoder 5, the OR gate Gn whose dip switch contact Sn is closed outputs a LOW level. is output to the data bus 4n. The model code set on the dip switch may be a code representative of the floppy disk device 2.

It is not necessarily representative of each model. Here, to give an example by model, in addition to 8-inch, 5-inch, and 3-inch floppy disk devices, a cassette device may also serve as an external storage device for storing the control program referred to herein. These +s, +)p codes are identified by a program (hereinafter referred to as an IPL program) that executes IPL, which will be described later.

Of course, the number of dip switches can be reduced as needed. Alternatively, it is also possible to set a unique value using hardware without using a tip switch.

FIG. 3 is a flowchart 1 showing the processing of the IPL program of the embodiment. In the figure, in step 1, the CPU
The main unit I accesses the device address of the floppy disk drive "f42" and reads the contents of the model encoder 7. This contents is determined by turning on each contact of the dip switch shown in Fig. 2,
It can be set to OFF. The dip switch is I
It is set in advance to generate a code according to the model identified by the PL program. In step 2, parameters corresponding to the model of the floppy disk device 2 are set in a controller (not shown), and then in step 3, the control program is loaded into the main memory. Next, in step 4, control full is passed to the read control program and the IPL is completed.

As mentioned in 2, the IPL program is not covered by IPL.
A1: Is the IFL program removed by reading out the storage device model? ! 1 (It becomes possible to automatically read control programs from various IPL target external storage devices by appropriately selecting a storage device access method.

(2) In the embodiment described above, the case has been described in which the IPL program knows (fixes) the device address of the external storage device to be IPLed. An example in which the IPL program does not fix this device address will be described below.

As mentioned above, there are various types of external storage devices that can be subjected to IPL, and examples include the cassette device 7i in addition to the floppy disk device. Got it. Now, if the floppy disk device that is the system's original IPL target external storage device breaks down, the IPL program or the target device is 1μ, plus 1, which is 1.
Now I have to wait for the floppy disk device to be repaired.
PL cannot be executed. However, if the cassette device is also a component device of the system, it may be convenient to execute IPL on the control program stored in the cassette.

According to the present invention, one of the contacts of the dip switch can be given a special flavor. Example λ is contact S8
IPL the external storage device υ when the external storage device υ is closed.
FIG. 4 is a flowchart 1 showing the control of the IPL program in this case. Step 1 is to read the encoders of the system 1 and the component devices. First, the IPL is performed on the floppy disk device, which is the external storage device to be subjected to IPL, but the read failure (Dip switch contact SI of the device, which was found to be malfunctioning depending on the disk) is opened.

Step 2 continues to determine whether or not the IPIJf-related device is being traded. In this case, since the determination is not satisfied, the process proceeds to step 6 and the device address is changed. Cassette device or IPL/
<If it is also used as a pick-up device, the device IS
The address is changed to point to the cassette device. The flow returns to step 1 and reads the encoder of the device. In advance, set the dip switch contact S H of the cassette device.
is closed, so the determination in step 2 is satisfied. In the following step 3, set the access paranoc according to the cassette device:il in the controller, etc., and step 4
Go forward one step and load the control program. Step 5 Pass the control Iμ to the loaded control program]
end.

As explained above, the present invention has various effects.
; Automatic IPL from the storage device is possible.

It becomes possible to flexibly handle the configuration of the microcomputer system according to the purpose and schedule of the user.

Further, according to the present invention, since the device address of the external storage device to be IPLed is not determined, it is possible to flexibly deal with failures of system component devices.

[Brief explanation of drawings]

Figure 1 is a block diagram 1 showing the configuration of an embodiment of IPL according to the present invention, 2nd (sub) I:l: A circuit diagram showing an example of a model encoder, and Figure 'a'53 is a block diagram showing an example of an IPL This is a flowchart illustrating the process of a program to be implemented, and a flowchart 1 illustrating another example of Q'S 4 iRI' (processing of a program that executes an IPL). Here, 1...CPU main body, 2...20 point-taking device, 3...address bus, 4 data path, 5
. . . IS rest coater, 6 . . output signal, 7-way model encoder.熍Word'1 appearance 卯人 Canon Street, Shikikai Nai agent br
Riyu Inuzuka j! Virtue-L J

Claims (4)

[Claims] (1) In the initial program load method that reads a control program from an external storage device into the main storage device and starts the control program, the type of external storage device set in the initial program load river is read from the processing device main body. An initial program loading method is characterized in that the type of external storage device is determined according to the read information, and the control program is read into the main storage device using an access method corresponding to the external storage device. (2) In the initial program row F method in which a control program is loaded from an external storage device into the main storage device and the control program is started, the external storage device is set as a target device for initial program row 1; The presence/absence and type of external storage device settings can be read from the processing device main body, the settings and type for the external storage device are determined according to the read information, and an access method corresponding to the external storage device with the settings is used. An initial program low F method characterized by loading the control program into a memory device. (3) The initial program loading method according to claim 2, characterized in that the presence/absence of settings and the type thereof are simultaneously read out from the processing device main body. (4) The initial program loading method according to claim 2, characterized in that the presence or absence of a setting is checked and the type of external storage device in which the setting is set is read from the processing device main body.