DE10247472A1 - Transmitting trace data in printing device involves distributing trace message between several data messages sent over data network if data quantity in trace message exceeds size of data block - Google Patents

Abstract

The method involves generating a trace message, sending the trace message from a microcontroler to the central memory medium over the network with data messages with header and data blocks. The trace message is distributed between several data messages if the data quantity in the trace message exceeds the size of a data block. The header block contains receiver identification, all arbitration information and all data block control information. The method involves generating a trace message, sending the trace message from a microcontroler to the central memory medium over the network with data messages with header and data blocks. The trace message is distributed between several data messages if the data quantity in the trace message exceeds the size of a data block. The header block contains receiver identification, all arbitration information and all control information for the data block, which contains only the trace data. Independent claims are also included for the following: (a) a control system for a printing device (b) and a printing device with an inventive control system.

Description

The invention relates to a method to transfer trace data in a printing device. Trace data is data which describe the current operation of a printing device and with conventional Print devices of a single assembly can be saved. In the event of an error, the trace data is provided by a maintenance technician read from the individual modules and based on the trace data it is determined which error has occurred on the printing device is. For this it is necessary that the maintenance technician to the each module connects a computer that uses it as a terminal to display the trace data stored in the module.

From the US-A-4,477,901 A device and a method are known in which the printing device is subdivided into several subsystems, the trace data on the one hand containing a general code that describes the respective subsystem and on the other hand the individual processes on the subsystems are subdivided into sub-steps so that in the event of an error a code is output for the last substep that has been properly executed. In this way, a service technician can determine which subsystem the error occurred in, and he can also determine very precisely which action, ie which sub-step, the error occurred.

For controlling individual modules or assemblies of a printing device is often the CAN bus used. This is a simple, inexpensive, serial data bus, with which data is transmitted very simply, but with a relatively low transmission rate can be. For transmission of data according to the CAN protocol Data of individual telegrams divided, each telegram from a data block and an identifier. The identifier can usually be up to to include 29 bits of data. Further control data are in the data block itself contain, for example, from which sender the data come or to which recipient they are sent or to which data unit the individual telegram is sent heard or how long the data block is.

The CAN bus or the corresponding one Protocol is in CAN Controller Error Network, basis and practice, 2nd edition, 1997, (ISBN 3-7785-2575-1) explained in detail. A CAN bus is usually used realized with a differential two-wire line. A CAN data telegram can a start bit, an 11-bit identifier, further seven control bits, 0 - 8 Data bytes and other control bits that follow the data bytes, include. The structure of a CAN data telegram can differ depending on the specification; so there is a CAN specification 2.0A and a CAN specification 2.0B. The arbitration is bitwise and executed without control. This means that the transmitter that is on the data bus is opposite others Channels based on its priority enforced, does not have to resend its telegram. For arbitration the control bits provided by the data bytes are used, the arbitration essentially by the bits of the identifier he follows.

A further development of the CAN bus is called PeliCAN, which is compared to the conventional CAN bus is equipped with further service features. By the company Philips will be called a stand-alone CAN controller SJA 1000, which fully supports the CAN 2.0B protocol and additionally can be operated in PeliCAN mode. This controller is in Datasheet dated January 4, 2000 described in detail.

The invention is based on the object Method and an arrangement for transferring trace data into to create a printing device that is quick and easy Allow access to the trace data and with a simple data network is feasible.

The task is carried out in the independent claims specified invention solved. advantageous Embodiments of the invention are specified in the subclaims.

• – Erzeugen einer Tracenachricht durch eine Braugruppe oder einen korrespondierenden Mikrokontroller,
• – Senden der Tracenachricht vom Mikrokontroller zum zentralen Speichermedium, wobei die Tracenachricht mittels Datentelegrammen über das Datennetzwerk übermittlt wird, und die Datentelegramme einen Header und einen Datenblock aufweisen,
• – die Tracenachricht auf mehrere Datentelegramme aufgeteilt wird, falls die Datenmenge der Tracenachricht größer als die von einem Datenblock aufnehmbare Datenmenge ist, wobei der Header eine Identifikation für den Empfänger, alle Informationen zum Arbitrieren und alle Steuerinformationen zu den Datenblöcken enthält und mit dem Datenblock nur Tracedaten der Tracenachricht übertragen werden.

The method according to the invention for transferring trace data into a printing device which has a plurality of microcontrollers for controlling assemblies of the printing device, the microcontrollers being connected via a data network and a central storage medium being arranged in the data network, comprises the following steps:

• Generating a trace message by a brewing group or a corresponding microcontroller,
• Sending the trace message from the microcontroller to the central storage medium, the trace message being transmitted by means of data telegrams via the data network, and the data telegrams having a header and a data block,
• - The trace message is divided into several data telegrams if the amount of data in the trace message is greater than the amount of data that can be recorded by a data block, the header containing identification for the recipient, all information for arbitration and all control information for the data blocks and with the data block only trace data the trace message are transmitted.

Since the trace data are transmitted to the central storage medium, they can be read out quickly and easily from the central storage medium. It is not necessary for a maintenance technician to access the individual modules separately. The method according to the invention, in which the trace message is transmitted by means of a data telegram, the data blocks of which are only trace data contain and all control data are integrated in the header, the data telegrams are optimally used so that the number of data telegrams for the transmission of trace messages is minimized and in addition the individual data telegrams can be managed solely by analyzing the header, that is, to combine one into several Distributed trace messages, only the header of the trace messages must be read and analyzed. In this way, on the one hand, the data traffic generated by the trace message and the effort for managing the data telegrams are kept low. This allows, despite the use of a simple, inexpensive data bus, such as the serial CAN bus, that it is possible to collect the trace data on a central storage medium and at the same time carry out general control tasks of the printing device via the data network used.

The header preferably contains a data telegram next to the length of the data block further control information, such as the Route ID, a status flag and a number of the data block, using which defines the data contained in the respective data block in more detail are. This additional control information can be found in the identification (Identifier) integrated. After another advantageous one Embodiment of the invention contain the data blocks Traced data in encoded form that is stored at the central storage facility can be decoded and displayed as full text on a control panel are.

The invention will be explained in more detail below explained using the drawings. The drawings show:

1 schematically a printing device with a data network and microcontrollers,

2 schematically a data network for a printing device,

3 a header of a data telegram, and

4 the flow of the method according to the invention in a flow chart.

With the method according to the invention are trace data in a printing device, the multiple microcontrollers for controlling assemblies of the printing device.

Such a printing device is, for example, a single sheet printer 1 ( 1 ) that has a paper input slot 2 with a device (not shown) for separating the paper sheets, not shown. The sheets of paper are along a transport route 3 from the paper input slot 2 to a printing unit 4 and an output slot 5 promoted.

The transport route is through a multitude of roller pairs 6 (in 1 only a single pair is shown to simplify the illustration) and corresponding guide devices are formed. The printing unit 4 has two pressure rollers 7 and an inking roller 8th on. The inking roller is used for electrographically operated printing rollers 8th exposed by means of an exposure unit (not shown) so that it takes up color particles at the exposed / unexposed areas. The color particles are from a corresponding storage container 9 via a feed line 10 and an adjustable valve 11 the inking roller 8th fed.

The printer 1 has a control system that has multiple microcontrollers 12 for driving the assemblies of the printing device. In the present invention, assemblies are that part of the printing device which is controlled by a microcontroller. Such assemblies are, for example, on the paper input chute 2 , the transport route 3 , the pressure value 4 , the output shaft 5 , etc. provided. The microcontrollers 12 are over a data network 13 with each other and with a central control device 14 connected. To the central control device 14 is a central storage medium 15 coupled, which is designed for example as a hard drive.

A typical structure of the data network 13 is schematically in 2 shown.

This data network 13 with the microcontrollers 12 is used to control the modules 16 , These assemblies are, for example, actuators, such as stepper motors for driving transport rollers, or sensor elements, such as light barriers, for determining the position of a sheet of paper. Each module is connected to a microcontroller or processor 12/1. In the present example, these microcontrollers 12/1 are divided into four groups, the group PI 1 for the paper input I, the group PI 2 for the paper input II, the group PU for the printing unit and the group PO for the paper output. The individual groups of microcontrollers are each connected via a CAN bus 13/1 to a so-called real-time microcontroller 12/2, which receives the messages from the microcontrollers 12/1 and which coordinates that control of the printing device real time is ensured. The two real-time microcontrollers 12/2, which are assigned to the two groups of paper input, are connected to one another by means of administrative microcontrollers 12/3. One of the management microcontrollers 12/3 or the real-time microcontrollers 12/2 assigned to the printing unit or paper output are connected to the central control device via an HSCX bus 13/2 14 connected to the central storage medium 15 connected.

During the operation of the printing device, trace data are generated on the individual assemblies, which describe the current status of the assemblies and thus the current operation of the printing device. This trace data can be generated both by the module itself and by the microcontrollers connected to it the. The trace data include, for example, values describing the operating state, such as a sensor signal, a message that confirms the execution of a certain process, or error messages.

The method for transmitting such a trace message is in 4 shown schematically. The method begins with step S1. After the generation of such a trace message S2, it is checked in step S3 whether the data volume of the trace message is larger than a predetermined data block. If this is the case, the process moves to step S4, in which the trace message is divided into parts, each of which is not larger than the predetermined size of the data block.

These parts are then each transmitted with a data telegram via the CAN bus 13/1 from the microcontrollers 12/1 to the real-time microcontrollers 12/2 (S5). Such a CAN data telegram comprises a header ( 3 ) and a data block. The header has an 11-bit identifier, which, based on a code for the microcontroller (Route_ID) to which the message is sent, has a 2-bit status flag which indicates whether the transmitted data block is a first, a middle one or is a last data block of the series of data blocks, and the number of the transmitted data block of the series of data blocks (= block number) exists. Each data block that is located between the first and last data block in the series is referred to as the middle data block. Because the block number 4 Bits, a trace message can be divided into a maximum of 16 parts.

The route ID for trace messages describes the sending microcontroller and the microcontroller to which the trace message is next transmitted, so that it is sent to the central control device 14 can be forwarded. The identifier is used to arbitrate the individual CAN telegrams in the CAN bus 13/1. In addition to the identifier, the header contains an unused data bit RTR and a code (DLC) describing the length of the data block transmitted in each case. This header is followed by the data block to be transmitted in the CAN telegram, which comprises a maximum of 8 bytes. The data block only contains trace data, ie data that describe the trace message. It contains no data to control the data blocks of a trace message distributed over several data blocks. The data blocks are managed solely on the basis of the status flag and the block number and reassembled at the recipient or intermediate recipient. As a result, the data block can be used completely for the transmission of “user data”. This keeps the amount of data traffic for the transmission of the trace data low and thus allows the use of a simple serial data bus, such as the CAN data bus. This is achieved by the double use of the Identifiers as “identifiers” and as carriers of the control data.

At the in 2 In the exemplary embodiment shown, the individual data blocks of a series of data blocks are already assembled in the data network in the case of the administrative microcontrollers 12/3 or the real-time microcontrollers 12/2 assigned to the printing unit and the paper output, each of which via the HSCX bus with the central control device 14 are connected. The trace messages are put together and according to the SNMP protocol via the HSCX bus to the central control device 14 transmitted further.

If it is determined in step S3, that the trace message is no larger than is the predetermined data block, the method goes from step S3 directly to step S5.

The trace data is preferably generated in coded form, that is to say that only a short code is generated for an error message instead of a text describing the error. A central control device 14 an interpreter is provided which interprets the encoded trace data and converts it into a readable text (S6). The trace data is stored in the form of this text on the central storage medium 15 stored (S7), with which the method according to the invention for transmitting the trace data is ended (S8).

During maintenance work, a maintenance technician can use a computer to contact the central control device 14 connect and the in the central storage medium 15 Retrieve collected trace data and analyze it for maintenance work. In a corresponding manner, the trace data can be called up quickly after an error occurring on the printing device in order to be able to determine the cause of the error.

Preferably, the trace messages are automatically sent to the central control device after they have been generated 14 sent. Within the scope of the invention, however, it is also possible for the individual trace messages to be stored, for example, on the real-time microcontrollers 12/2 or the administration microcontrollers 12/3, each of which is a group of modules 16 assigned. If necessary, this data can then be sent via the central control device 14 can be called up by individual microcontrollers 12/2 or 12/3. At least some of the trace data are preferably also stored locally, so that a local examination of the states of the individual modules is possible in the event of an error in the data network. In principle, it is also possible to transfer part of the trace data directly to the modules 16 intermediate microcontrollers 12/1.

The invention is based on a embodiment described a printing device which is a cut sheet printer. Within the scope of the invention, such a printing device can also be a continuous sheet printer or be a copier.

The invention is briefly summarized below:
With the method according to the invention, trace data are collected and stored on a central storage medium. A simple data bus can be used for this purpose, via which the trace messages are transmitted by means of data telegrams which have a header and a data block. Only user data are contained in the data block, whereas the header both serves to arbitrate the individual data telegrams and also contains control information relating to the data blocks.

1

Single-sheet printer

2

Paper input tray

3

transport

4

printing unit

5

output tray

6

roller pair

7

platen

8th

Inking roller

9

reservoir

10

supply line

11

Valve

12

microcontroller

13

Data network

14

central control device

15

central storage medium

16

module

Claims (12)

Method for transmitting trace data in a printing device, which has several microcontrollers ( 12 ) for controlling assemblies ( 16 ) of the printing device ( 1 ), the microcontroller ( 12 ) via a data network ( 13 ) are connected, and in the data network ( 13 ) a central storage medium ( 15 ) is arranged, comprising the steps: - Generation of a trace message by an assembly ( 16 ) or a corresponding microcontroller ( 12 ), - sending the trace message from the microcontroller ( 12 ) to the central storage medium ( 15 ), the trace message using data telegrams via the data network ( 13 ) is transmitted, and the data telegrams have a header and a data block, - the trace message is divided into several data telegrams if the data volume of the trace message is larger than the data quantity that can be recorded by a data block, the header identifying the recipient, all information on the Arbitrate and contains all control information for the data blocks and only the trace data of the trace message are transmitted with the data block. A method according to claim 1, characterized in that as a data network ( 13 ) a CAN bus is used in at least one area and the data telegrams are transmitted as CAN data telegrams in the area of the CAN bus. Method according to one of claims 1 or 2, characterized in that that the header has an identifier in which a code for the microcontroller (Route_ID) to which the trace message is sent a 2 bit status flag is entered with which it is indicated whether the transmitted Data block a first, a middle or a last data block a series of data blocks and the number of the transmitted Data block of the series of data blocks is entered. A method according to claim 3, characterized in that the identifier consists of 11 bits. Method according to one of claims 1 to 4, characterized in that that the header has a code (DLC) that is the length of the Data block describes. Method according to one of claims 1 to 4, characterized in that that the data telegram consists only of the header and the data block. Method according to one of claims 1 to 6, characterized in that that a trace message is automatically generated immediately transmitted to the central storage medium becomes. Method according to one of claims 1 to 7, characterized in that that the trace data is transmitted in coded form over the data network and decoded on the central storage medium. Control system for a printing device, which comprises a plurality of microcontrollers connected via a data network ( 12 ) for controlling assemblies ( 16 ) of the printing device ( 1 ) and a central storage medium ( 15 ), the control system being designed such that trace data according to a method according to one of claims 1 to 8 in the data network ( 13 ) to the central storage medium ( 15 ) be transmitted. Printing device comprising a control system according to Claim 9. Printing device according to claim 10, characterized in that the central storage medium ( 15 ) is a hard drive. Printing device according to one of claims 10 or 11, characterized in that the Da network ( 13 ) has at least one section with a serial data bus, which is in particular a CAN bus.