JPH06324890A - Memory access method - Google Patents

Abstract

PURPOSE:To provide a memory access method without requiring to change software even when the address of an area representing a state and a bit position representing normalcy/abnormality are changed, and requiring few handling time for change. CONSTITUTION:This method is constituted in such a way that a position information table 1 provided with the column of an area on which a state name is written, the address column of the area on which the state name is written, a column representing the normalcy/abnormality of each state, and a column which indicates the bit position representing the normalcy/abnormality of the state, and an access means 2 are provided, and the access means 2 refers to the position information table 1, and finds the address of the area on which a certain state is written and the bit position representing the normalcy/ abnormality of the state, and writes the state on a found position or reads it out from the found position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a memory with, for example, an alarm when a signal is not detected, an alarm when data is out of a frame, and an alarm when a clock is down. A writing area is provided, and when the communication device or the like is in the above state, the bit at the predetermined bit position of the corresponding area is set to 1, and when not in the state, the bit position is set to 0, and the CPU reads it. The present invention relates to a memory access method in which software is not required to be changed even if the address of each area is changed or the bit position is changed.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram of a main part of an apparatus for notifying a CPU of the state of an example of a transmission apparatus.

In FIG. 5, the transmission device 11 notifies the CPU 10 of an alarm when the signal is not detected, an alarm when the data is out of the frame, and an alarm when the clock is down. In this case, an area for writing each alarm is provided on the memory 3, and when the transmission device is in the above state, the bit at a predetermined bit position in the corresponding area is set to 1, and when not in the above state, it is set to 0, The CPU 10 is reading this. In the memory 3 of FIG. 5, the alarm is written from the top, where the last bit of the 8 bits is 1, the last bit of the next 8 bits is 0, and the next 8 bits. 2 is the second place from the end, and 12 is a ROM that stores programs, etc.
Is.

[0004]

However, when the computer changes, the address of the area indicating each state and the bit position indicating normal or abnormal may change.

In this case, conventionally, it is necessary to change the contents indicating the address and the bit position of the corresponding portion of the software, which causes a problem that it takes much labor. According to the present invention, the software does not have to be changed even if the address of the area indicating the state, the bit position indicating normality, or the abnormality is changed.
The purpose of the present invention is to provide a memory access method that is easy to change.

[0006]

FIG. 1 is a block diagram showing the principle of the present invention. As shown in FIG. 1, when accessing a bit position indicating a normal or abnormal state of a region in which a certain state is written in the memory 3, a column for writing a state name, an address column for writing a state name, The position information table 1 and the access means 2 each having a column indicating normality / abnormality, a column indicating bit position indicating normality / abnormality, and an access unit 2 are provided.
A structure in which the access means 2 refers to the position information table 1 to obtain an address of a region in which a certain state is to be written and a bit position indicating normality / abnormality of the state, and writes to the obtained position, or reads from the obtained position And

[0007]

According to the present invention, the address of the area indicating the state,
When the bit position indicating normal or abnormal is changed, the address of the area in which the changed state name of the position information table 1 is written, and the bit position indicating normal or abnormal in the changed state are changed. 2, the position information table 1 is referred to, and the address of the area in which a certain state is written and the bit position indicating normality / abnormality are obtained, and writing is performed at the obtained position or read from the obtained position, so the software is changed. You can access it without it, so you can change it less.

[0008]

FIG. 2 is a diagram showing a position information table of an embodiment of the present invention, FIG. 3 is a flowchart of a writing process of the embodiment of the present invention, and FIG. 4 is a flowchart of a reading process of the embodiment of the present invention.

Addresses of areas for writing an alarm when a signal is not detected, an alarm when a data is out of a frame, and an alarm when a clock is down are 1000 and 1000 as shown in FIG. , 1001, and the bit positions indicating normality and abnormality are L as shown in FIG.
Assuming that the position is 1, 2, 1 bit from SB, as shown in FIG. 2, in the position information table, in the column of the area for writing the status name, the signal non-detection status alarm, the frame protruding alarm, the clock down In the address field of the area for writing the alarm and the state name, 1000,100 from the top
0, 1001 are written, NO, ALM, ALM occurrence are written in the columns showing normal and abnormal states, respectively, and columns 1, 2 from the top are written in the columns showing bit positions showing normal and abnormal states.
Write 1.

As the access means, the transmission device 1 shown in FIG.
When 1 is a process of writing to the memory 3, the process is as shown in FIG. 3, and when the CPU 10 of FIG. 5 is a process of reading from the memory 3, the process is as shown in FIG.

Therefore, the alarm that is in the signal undetected state is C
The process of writing to the memory 3 by the transmission device 11 will be described with reference to FIG. In step 1, if the signal non-detection state alarm and abnormality are input,
In step 2, referring to the position information table of FIG. 2, 100 of the address of the signal undetected state alarm area and bit position 1 indicating normal or abnormal are obtained, and in step 3, the address 1000 of the memory If the bit to be written in this address is, for example, 8 bits, 1 is written in the 8th bit.

Next, the reading process will be described with reference to FIG. When the signal non-detection state alarm is input in step 1, the address information table 1000 of FIG. From the location information table of
1 in bit position 1000 indicating normal or abnormal address
Then, in step 4, the last bit 1 of 1000 of the address is read, and it is found that the signal is not detected.

That is, the address of the area showing the status, normal,
When the bit position indicating an abnormality changes, the position information table 1
If you change the address of the area to write the changed state name and the bit position that indicates whether the changed state is normal or abnormal, you can access without changing the software, so there is little effort to change. Become.

[0014]

As described in detail above, according to the present invention, even if the address of the area indicating the state and the bit position indicating normality or abnormality change, the software can be changed by changing the corresponding portion of the position information table. Does not have to be changed, which has the effect of reducing the trouble of changing.

[Brief description of drawings]

FIG. 1 is a block diagram of the principle of the present invention,

FIG. 2 is a diagram showing a position information table according to the embodiment of the present invention,

FIG. 3 is a flowchart of a writing process according to an embodiment of the present invention,

FIG. 4 is a flow chart of read processing according to the embodiment of the present invention,

FIG. 5 is a block diagram of a main part of a device for notifying the CPU side of the status of an example of the transmission device.

[Explanation of symbols]

 1 is a position information table, 2 is an access means, 3 is a memory, 10 is a CPU, 11 is a transmission device, and 12 is a ROM.

Claims (1)

[Claims] 1. When accessing a bit position indicating a normal or abnormal state of an area in which a certain state name is written in a memory (3), a column for writing the state name, an address column for writing the state name, and A position information table (1) having a column indicating normality / abnormality of state, a column indicating bit position indicating normality / abnormality of state, and an access means (2) are provided, and the position is set by the access means (2). The information table (1) is referred to, and the address of the area in which a certain state is written and the bit position indicating normality / abnormality of the state are obtained, and writing is performed at the obtained position or read from the obtained position. Memory access method.