DE2500841A1 - TRACKING DEVICE - Google Patents

Description

Patent attorney
Dipl.-Phys. Leo Thul

Stuttgart

M.J.M. Archer et al 2-3-1-1

INTERNATIONAL STANDARD ELECTRIC CORPORATION, NEW YORK

Tracking device

The invention relates to a tracking device for plants with at least one central data processing unit and associated memory, especially for central Units for controlling telecommunications switching systems,

The task of such a tracking device is to track the functional sequence within a data processing system to make it transparent for auditing purposes. It is there it is particularly important to run certain parts of the data processing program in real time, since some proper processes, but also some errors only occur at a certain processing speed. on the other hand There are important milestones within extensive program workflows that can only be used retrospectively allow a correct assessment of the function of the data processing system over a large period of observation. This task is given in particular in the case of telecommunications switching systems that are controlled by central units

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can be controlled, whereby a long-term observation of certain conditions or statistical quantities is often required. The tracking device according to the invention is characterized by

- A storage device _r which is connected to the processing unit to be observed and receives tracking information from it with each storage process, which on the one hand consists of address and operating mode characters that are transmitted from the processing unit to its memory, and which on the other hand consists of indicators that the Identify the type of storage process affected,

- and an addressing unit, on the one hand the indicators sent by the processing unit and on the other hand receives control characters from a control unit of the tracking device that indicate the desired mode of operation of the memory and the type of process to be stored, the addressing unit identifying the address denotes the storage device to which either tracking information is to be written or tracking information is to be read to be transmitted to the control unit.

A special embodiment ^ of the address you purity of Tracking device is characterized by the following components:

- a logical control unit, which is made up of the by the control unit sent control characters other control characters that identify the type of tracking information to be saved.

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draw, and generate read and write commands for the tracking information;

a register to hold the type of tracking information to be stored, which is provided by the logic control unit was determined;

- a logic circuit that, if the contents of the register match the decoded indicators a matching mark of an offered tracking information gives up;

- A reversible address counter with associated circuitry that displays the compliance mark and read and Receives write commands and displays addresses at which the tracking information is written or read shall be.

Further refinements of the subject matter of the invention can be found in the further subclaims.

The invention is explained below with reference to the embodiment shown in the accompanying drawings :

Fig.1 shows a block diagram of a system with a central unit with memory, and a tracking device according to the invention with associated Steering;

2 shows a tracking device and its relationship with other plant units according to the invention.

In Fig.l the central unit 1 with the memory 2 is over connected to a data bus. In particular, the central unit 1 transmits addresses and function type characters to the memory 2, affected by the current memory operation

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are. According to the invention, this data also becomes a tracking device 3 and fed there to a buffer register 33 assigned to a tracking memory 31. That Buffer register 33 also receives from the central unit 1 the so-called "indicators" which identify the type of operation of the memory and which together with the Address and function type characters are the tracking information transferred from buffer register 33 to tracking memory 31 form. The "indicators" are also transmitted to the logical addressing unit 32, which is provided by the control unit 4 receives characters that determine the operation of the trace memory and, if applicable, the ones to storing memory function type identifier. The logical addressing unit 32 shows the trace memory 31 either indicates the memory location where the tracking information in the buffer register 33 is to be written, if a storage is requested by the control unit 4, or it indicates the storage location at which this information should be read when the contents of the trace memory are needed. The control unit 4 includes a Instruction unit 41 for controlling the tracking device which receives data from the tracking memory. the Control signals can also be entered from a desk 42 that allows an operator to control the operation the establishment, start and. Set the end of storage and start of reading. In the example, the Control signals indicate whether the tracking memory is to be written to or read from, and when writing is performed, it is displayed whether it is continuous or limited writing and what data is being written should. From the command unit 41 or from the control panel 42

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A wide variety of types of tracking information can be set. If a full examination of the work of the considered central unit is required _f then all memory operations should the central unit are pursued, which implies that all the tracking information storage operations of all types are included in the trace memory one respect. If, on the other hand, the content of the trace memory is to reflect a longer working period, then only trace information relating to any type of instruction, in particular relating to branch instructions, is stored; In the case of branch instructions, the origin and destination must be recorded.

The device according to the invention allows the type of tracking information to be selected as the type of storage in order to simplify troubleshooting or to determine the frequency of a command. If the tracking device is used to investigate what is going on in the central unit before a fault occurs, then the type of storage is continuous; This means that the tracking memory is addressed cyclically, with a memory capacity of 2 ^l words, the address O is activated again after the address 2 -1. However, in order to find out the frequency of certain commands, the storage is terminated as soon as 2 tracking items of information are written in the memory. It can be seen that regardless of the type of storage selected, the largest amount of tracking information is 2®; the memory content includes the last 2 ^{N storage processes in the case of continuous memories and the last 2 N} storage processes of the selected type in the case of discontinuous memories,

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The diagram in FIG. 2 makes it easier to understand the relationship between the tracking device according to the invention and the other system units and the mode of operation the tracking device, in particular the addressing units and the functionality of the tracking device, in particular the addressing unit 32. It is again the central unit 1, the buffer register 33 for the tracking memory 31, the command unit 41 and the control panel 42 indicated.

The logical addressing unit 32 comprises:

- A logic control unit 321, which from the Command unit 41 or control characters sent by the control panel 42, the necessary for the function of the device Commands generated;

a register 322 which stores the type of stores to be retained in the trace memory;

a decoder 324 which decodes flags sent from the central unit 1 to the tracking device for each storage operation to be sent;

a logic circuit 323 mainly responsible for the comparison between the content of the register 322 and that of the Decoder 324 executes data sent;

a reversible address counter 325 with associated auxiliary circuits (AND circuits 326 and 327, flip-flops 328 and 329); this counter feeds the tracking memory 31 either with the address at which the tracking information of the buffer register 33 is to be written, or with the address at which information is to be read, if necessary, when reading the memory will.

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It has already been explained above that the central unit supplies the tracking device with addresses, operating mode symbols and indicators which identify the type of storage process connected. If it is assumed that a continuous storage of tracking information is desired which relate to the reading of commands of all kinds, then the control unit 4 (either the command unit 41 or the control panel 42) sends the logic control unit 321 control characters which are the start command for the storage and identify the type of memory function required (reading commands). After decoding the commands sent by the control unit 4, the control unit 321 registers the type of memory function selected in the register 322 and commands that the contents of the buffer register 33 be retained in the memory 31 while the flip-flop 328 is set to state 1 at the same time decoded by the decoder 324 indicators of the logic circuit 323 are fed to _t In each of the central unit 1 performed storage process which compares the contents of the register 322 with the direction indicated by the indicators Art. The logic circuit 323 opens the AND circuit 327 when the type indicated by the central unit 1 matches the selected type (reading of commands). In this way, the AND circuit 327 is opened by the logic circuit 323 when the tracking information sent by the central unit corresponds to a mode of operation which it is desired to store (reading of commands). When the logic control unit 321 issues a store command, the trace memory 31 stores all trace information contained in the buffer register 33 on the

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by the reversible address counter 325 marked place. The address counter was checked before the start of saving of the logic control unit 321 and is reset with each pulse at the output of the AND circuit 327 switched one step further, so this happens every time when the flip-flop 328 is at the same time in the 1 state and a positive comparison signal is present at the output of the logic circuit 323. Hence will the address counter is only incremented by one when the tracking information is actually stored otherwise it will display the same address, so that new tracking information will be sent to the same

xlie
Place how \ previous tracking information to be skipped is written. This method makes the storage time independent of the calculation time of the address. Because of the continuous storage type required by the control unit 4, the (2 ^L + 1) -th tracking information (in the case of a tracking memory with 2 words) is returned to address O, with the previously information given to this address is overwritten. The address counter 325 thus acts as a ring counter.

On the other hand, if discrete samples are desired, then work the address counter 325 is not a ring counter; the logic control unit 321 can in this case, for example, on the one hand send an interrupt character to command unit 41,

N when tracking information has been stored at the 2nd address, and on the other hand the tracking memory notify you of the end of the registration process and then reset flip-flop 328. The address counter 325

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is stopped, the control unit 4 is informed that tracking information is available and the tracking memory can be read.

However, the storage of the tracking information can also be stopped at any address K (CKK ^ 2 ^ -I) if either an error was detected in the central unit 1 or if by the control unit 4 a hold command was sent; therefore there must be some additional information indicating whether the address counter the address K displays for the first time or not, in order to be able to decide whether the one in the memory 31 can be

Tracking information of the addresses K + 1 to 2 -1 into consideration to be drawn or not. This additional information is obtained with the help of the flip-flop 329, the is brought to position 1 when the address counter is postponed; each start command sent by logic control unit 321 sets the additional flip-flop 329 back.

If the control unit 4 reads out the availability memory is requested, then the control unit 4 sends appropriate command symbols to the logic control unit 321. The logic control unit 321 on the one hand sends the read command to the tracking memory 31 and at the same time provides the flip-flop 328 back, on the other hand it reads the value K of the address counter and the state of the additional Flip-flops 329, then the trace memory 31 sends to the instruction unit 41 the information from the address counter tracking information read at the designated address.

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The content of the counter is displayed with each pulse at the output the AND circuit 326 is reduced by one, that is, each time information is received in the control unit 4.

When the address counter reaches the value O, reading is ended _f if the read value K is equal to the value 2 ^N -1 or if the additional flip-flop is in state O, or reading is continued until address K is reached + l continued if the additional flip-flop is in state 1 and the condition 0 <K <2 ^N -l is met.

As already indicated, very different types of tracking information can be stored in the tracking memory 31 are: Information about storage processes of all kinds, about read processes in the memory, about command read processes or via branch instruction reads. In the first three types, the decoder 324 decoded indicators are compared with the content of the register 322 in the logic circuit 323 in which Last but not least, it is important to have the trace information associated with the branch instruction as well the tracking information associated with the subsequent command to know. The second piece of information can be obtained because it is the first after the branch instruction Command acts. To enable this command to be followed up, logic circuit 323 opens the AND circuit 327 after storing the second command, this causes logic circuit 323 to be able to recognize the first instruction after a branch instruction.

So the trace information for branch instructions to store, the logic circuit 323 opens the AND

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Circuit 327, if either the comparison of the instruction type is positive (the indicators indicate a branch instruction) , or if the indicators identify any command and this after the first command is a branch instruction. This logical function can easily be implemented with conventional components.

The command unit 41 must be able to use the tracking device 3 to be supplied with control characters for storing and reading the selected. Tracking information is required.

In the example described, a central unit is used, for which the tracking device is a peripheral unit represents. If the central unit to be observed is part of a plant with several central processing units then one of these may be the command unit for the tracking device assigned to another central unit be. However, if the system only comprises one central unit, then this can be used as a command unit for the tracking device serve, which is assigned to her according to the invention itself.

In the latter configuration, however, it should be noted that the tracking device as a peripheral unit of the central Unity is to be considered and this causes some consequences, in particular it is not possible for the central unit processes other data when reading tracking information; this degrades their performance unless the reading process is carried out after an error has been detected, the central unit being at a standstill anyway, which is shown in often occurs in practice,

6 claims
2 sheets of drawings, 2. Fig.

1 List of Reference Numbers ^,

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Claims (6)

M.J.M. Archer et al 2-3-1-1 Claims Tracking device for systems with at least one central data processing unit and associated memory, in particular for central units for controlling telecommunications switching systems, characterized by - a storage device _r which is connected to the processing unit (1) to be observed and which receives tracking information from it with each storage process, which on the one hand consists of address and operating mode characters which are transmitted from the processing unit (1) to its memory (31), and which, on the other hand, consists of indicators that identify the type of storage process concerned, - and an addressing unit (32), which on the one hand the indicators sent by the processing unit (1) and on the other hand from a control unit (4) of the tracking device receives control characters that the desired mode of operation ■ of the memory and the type of process to be stored, the addressing unit (32) indicating the address denotes the storage device to which either tracking information is to be written or tracking information is to be read to be transmitted to the control unit. 2. Tracking device according to claim 1, characterized in that the addressing unit (32) has the following components: 509830/0850 - 13 M.J.M. Archer et al 2-3-1-1 - A logical control unit (321), which from the control characters sent by the control unit (4) other control characters, the type of tracking information to be stored tag, and generate read and write commands for the tracking information; - a register (322) for the type of tracking information to be stored hold that determined by the control logic unit (321); - A logic circuit (323) which, when the Contents of the register (322) with the decoded indicators of an offered tracking information a match mark gives up; - A reversible address counter (325) with associated circuitry, which shows the match and read and Receives write commands and displays addresses at which the tracking information is written or read target. 3. Tracking device according to claim 1 or 2, characterized in that the storage device has the following components: - A buffer register (33) in which the tracking information is formed from the characters sent by the processing unit (1) will; - A tracking memory (31), in which according to the from commands sent to the control unit, the tracking information is either written in or read out, with the Address of the tracking memory (31) is determined in each case from the status of the address counter (325). 509830/0850 M.J.M. Archer et al 2-3-1-1 4. Tracking device according to claim 1, 2 or 3, characterized in that, in the case of writing in the tracking memory (31), the content of the address counter (325) for each coincidence character of the logic circuit (323) is increased by one, 5. Tracking device according to one of claims 1 to 3 _f, characterized in that in the case of reading from the tracking memory (31) the content of the address counter (325) is decremented by one each time there is tracking information from the tracking memory in the control unit was received, 6. Tracking device according to one of claims 1 to 5 _r, characterized in that additional information is stored which indicates whether a certain address of the tracking memory after the start of a read or write has already been reached before gear or not. 509830/0 8 SO