DE102014101162A1 - Integrated electronic circuit for a control module for mounting on a consumable cartridge, control module and consumable cartridge for a printer - Google Patents

Abstract

The invention relates to an integrated electronic circuit (2) for a control module (1) for attachment to a consumable cartridge, at least comprising the functional blocks interconnected via processor bus lines: • Programmable code memory processor core • Readable and rewritable data memory • Serial bidirectional interface where • the processor core is cryptRISC processor core is formed, which has a RISC processor architecture with additional cryptographic commands, and the bidirectional interface with respect to the wiring of the contact elements (3) and the data transmission protocols used is freely programmable.

Description

• • Prozessorkern mit programmierbarem Codespeicher,
• • lesbarer und wiederbeschreibbarer Datenspeicher,
• • serielle bidirektionale (I/O) Schnittstelle.

The present invention relates to an integrated electronic circuit for a control module for mounting on a consumable cartridge, at least comprising the function blocks interconnected via processor bus lines:

• • processor core with programmable code memory,
• • readable and rewriteable data storage,
• • serial bidirectional (I / O) interface.

A control module with such a circuit and a consumable cartridge, such as an ink or toner cartridge for a printer with such a control module are also the subject of the invention.

In the prior art, printers, such as ink jet and laser printers, are known in a variety of different embodiments. For the supply of consumable usually disposable disposable consumable containers, so-called consumable cartridges are used, for example, ink or toner cartridges, which are hereinafter referred to as cartridges. These are used for operation in corresponding cartridge receiving devices in the printer. When a cartridge is empty, it is removed from the printer, disposed of and replaced with a filled cartridge, or refilled with supplies.

Usually cartridges are provided with an electronic control module, which is used for authentication of the cartridge and for storing specific data includes a rewritable data memory. The control module is connected to electrical contact elements, which are externally accessible contact surfaces. When a cartridge is inserted into a printer, it encounters printer contactors located in the cartridge receptacle of the printer. The printer contact elements are internally connected to the control lines of the printer, via which the printer in addition to the supply voltage for a serial data transmission protocol and data signals are transmitted. In this way, the printer can read data from the storage element of the ink cartridge, such as type, capacity, ink, toner, color, etc., and data can be written to memory, such as the current residual ink level. As a result, a user can be informed at any time about the current ink level of an ink cartridge and, if necessary, be prompted to replace an empty or soon-used cartridge in a timely manner.

While at the beginning of development simple designs of control modules have been used in the form of memory modules, which consisted essentially of memory cells and a fixed input / output control logic, are currently used advanced developments in which complex data operations are performed and the data exchange with a Printer via specially adapted interfaces. For reasons of efficiency and cost, the essential electronic functions of such a complex control module are combined in an integrated circuit, a monolithic component which has digital functional blocks formed on a semiconductor substrate which communicate with one another via an internal processor bus. The main functional blocks include a processor core including program code memory (code memory), readable and / or rewritable memory areas and a serial bidirectional interface for data communication. To connect the power supply and for the exchange of data with the printer, the circuit has outwardly led out contact elements (pins), which are connected to the contact elements of the control module.

The essential purpose of the control modules today is to bind the users of the printer to the exclusive use of the appropriate consumable, for example, original ink cartridges of each printer manufacturer. For this purpose, the semiconductor memory means are increasingly equipped with complex logic circuits for authentication, which also have cryptographic data encryption means. This makes it technically expensive to provide compatible replacement ink cartridges, even though in fact only the ink level is to be stored on the ink cartridges. Such a control module is for example in the WO 2009 / 145775A1 described.

Another problem with providing replacement cartridges is that each printer manufacturer applies its own non-standard data transfer protocols. So will in the EP 1 736 318 A2 a control module is described, which has an interface with two power supply and two data transmission lines and a light emission control circuit for optical data transmission to the printer, which is also controlled by the integrated circuit. That from the EP 2 361 770 A1 known control module of another printer manufacturer has three data and two power supply lines, another printer manufacturer used according to the EP 2 607 082 A1 a total of three combined data power supply lines.

In view of the above-discussed problems in the prior art, the invention is based on the motivation to provide a universal integrated circuit for a control module, which can flexibly execute different authentication methods and is adaptable to a multiplicity of different data transmission protocols and physically different interfaces.

• • der Prozessorkern als cryptRISC-Prozessorkern ausgebildet ist, der eine RISC-Prozessorarchitektur mit zusätzlichen kryptographischen Befehlen aufweist, und
• • die bidirektionale Schnittstelle bezüglich der Beschaltung der Kontaktelemente (pins) und der eingesetzten Datenübertragungsprotokolle frei programmierbar ausgebildet ist.

To solve the above problem, the invention proposes that

• The processor core is designed as a cryptRISC processor core, which has a RISC processor architecture with additional cryptographic commands, and
• • The bidirectional interface with respect to the wiring of the contact elements (pins) and the data transmission protocols used is freely programmable.

The peculiarity of the invention is that a for the specific application - namely cryptographically encrypted data exchange - particularly well suited, while highly efficient processor core is used, which can be programmed over a wide-programmable, i. freely configurable interface (interface) can communicate with a printer.

The cryptRISC processor core employed in the invention is, in principle, a Reduced Instruction Set Computer (RISC) processor, i. a processor with a reduced instruction set, which allows a simple and inexpensive chip design and a high operating speed (clock frequency). The cryptRISC design continues this approach, extending the instruction set with typical cryptographic instructions (crypto instructions). For example, a typical instruction set includes the following instructions: permutation (bit-oriented, bit-oriented), multiplication / division, Galois field arithmetic (matrix multiplication, inverse multiplication), affine and inverse affine transformation, rotation, shifting, table operations (Table look-up: 4/8/32 bit substitution, 16-256 table entries), arithmetic operations (ADD, SUB) and logical operations (XOR, OR, AND, NOT). If necessary, further specific instructions can be implemented. The particular advantage of such a cryptRISC processor core is that common cryptographic algorithms such as DES (Data Encryption Standard) or AES (Advanced Encryption Standard) can be performed highly efficiently. Thanks to the integrated crypto commands, a cryptRISC processor core can achieve a much higher processing speed than a conventional processor with additional crypto coprocessor. This is of particular importance for use in a consumables cartridge control module because, in this particular application, the data transfer rate is typically so high that simple substitute solutions based on standard microcontrollers will not work.

Further advantages of cryptRISC processor cores are that they can be flexibly programmed to process a wide variety of data transmission protocols and can also be implemented cost-effectively as an ASIC (Application Specific Integrated Circuit).

Another essential advantage of the invention results from the fact that the interface is freely configurable by appropriate programming within wide limits. On the one hand, this concerns the physical connections, such as the different numbers and occupancy of the data and supply voltage lines in different printer types (see above). On the other hand, the data processing can be adapted by appropriate programming to a variety of data transmission protocols, which are usually printer manufacturer-specific, proprietary protocols. In addition, contactless data transmission methods can also be realized, for example opto-electronically by controlling light-emitting elements (LEDs or the like).

By combining a cryptRISC processor core according to the invention with a freely configurable interface, a control module according to the invention for a multiplicity of different types of cartridges and printers from different printer manufacturers can be used by appropriate programming and use of a contact plate with adapted contact geometry. This significantly reduces both the development and manufacturing costs of compatible third-party cartridges.

Conveniently, an oscillator for the processor clock is integrated. This determines the operating speed of the processor core.

Preferably, a random number generator for generating true random numbers (TRNG) is integrated. As a result, random numbers required for cryptographic operations can be provided efficiently.

It is furthermore advantageous that an encryption unit is integrated. This is a circuit block in which algorithms for special cryptographic standard methods are hardwired, for example for DES (data encryption standard) method or 3DES ( triple DES). As a result, the encryption methods can be used particularly efficiently.

Embodiments of the invention are explained in more detail below with reference to drawings. In detail show:

1 a block diagram of a circuit according to the invention,

2 a control module with a circuit according to the invention according to 1 .

3 a block diagram of a control module according to the prior art,

4 an ink cartridge with a control module according to 2 ,

In 1 schematically is an inventive control module 1 shown. It comprises an integrated circuit according to the invention 2 , which is shown as a block diagram, with contact elements 3 are connected, ie externally accessible, conductive contact surfaces (also referred to as terminals or Kontakpads).

• – cryptRISC: Prozessorkern, der auf RISC-Architektur basiert und für kryptographische Operationen optimiert ist.
• – IO: frei programmierbare, serielle bidirektionale Schnittstelle (Interface). Durch eine entsprechende Programmierung, die in einem Konfigurations-Speicher gespeichert wird, kann die Schnittstelle erfindungsgemäß in weiten Grenzen konfiguriert werden. Beispielsweise kann die Belegung der nach außen herausgeführten Kontaktelemente vorgegeben werden, um ein Ein-, Zwei- oder Mehrdraht-Interface zu realisieren. Entsprechend dem jeweils angewendeten Datenaustauschprotokoll erfolgt die Aufbereitung der vom Drucker empfangenen und zum Drucker gesendeten Datensignale.
• – SPU: Signalverarbeitungseinheit. In diesem Schaltungsblock der Schnittstelle werden Daten- und Steuersignale vom Drucker empfangen und an diesen gesendet. Die SPU kann erfindungsgemäß ebenfalls konfiguriert werden.
• – PWM: Pulsweitenmodulator. Durch Pulsweitenmodulation können analoge Signale nachgebildet werden, beispielsweise Ströme zur Simulation von ohmschen Widerständen.
• – Code OTP: Codespeicher für cryptRISC-Programmierung. Der Codespeicher ist bevorzugt als beschreibbarer oder mehrfach wiederbeschreibbarer, nichtflüchtiger Speicher ausgebildet (EEPROM) und nimmt das Betriebsprogramm für den Prozessorkern auf. Dadurch erfolgt die Anpassung des Steuermoduls an die unterschiedlichen geforderten Anwendungen auf Verbrauchsmaterialkartuschen für unterschiedliche Drucker.
• – Data FERAM: wiederbeschreibbarer nichtflüchtiger Datenspeicher. FERAM-Speicher haben eine besonders hohe Speichergeschwindigkeit und ermöglichen daher eine flexible Anpassung an Anwendungen mit hoher Datenverarbeitungsgeschwindigkeit. Dadurch können auch proprietäre Hochgeschwindigkeits-Datenübertragungsprotokolle, wie sie von Druckerherstellern zur Kommunikation des Druckers mit Steuermodulen auf Verbrauchsmaterialkartuschen eingesetzt werden, universell umgesetzt werden.
• – Data SRAM: wiederbeschreibbarer Datenspeicher
• – CFG: Konfigurationseinheit
• – TRNG: Zufallszahlengenerator zur Erzeugung echter Zufallszahlen
• – DES/3DES: Verschlüsselungseinheit für die Verschlüsselungsstandards DES bzw. 3DES. Die Standard-Krypto-Algorithmen werden fest verschaltet bereitgestellt. Dadurch wird eine hohe Verarbeitungsgeschwindigkeit insbesondere für kryptographische Operationen ermöglicht.
• – RC OSC: Oszillator für Prozessortakt
• – POR: Zurücksetzen beim Einschalten (power-on-reset)
• – TEST:s Testschaltung

The circuit 2 has a plurality of integrated function blocks:

• - cryptRISC: processor core based on RISC architecture optimized for cryptographic operations.
• - IO: freely programmable, serial bidirectional interface. By appropriate programming, which is stored in a configuration memory, the interface can be configured according to the invention within wide limits. For example, the assignment of the lead out to the outside contact elements can be specified to realize a one-, two- or multi-wire interface. In accordance with the respectively used data exchange protocol, the processing of the data signals received by the printer and sent to the printer takes place.
• - SPU: signal processing unit. In this circuit block of the interface, data and control signals are received from and sent to the printer. The SPU can also be configured according to the invention.
• - PWM: pulse width modulator. By pulse width modulation analog signals can be simulated, for example, currents for simulating ohmic resistances.
• - Code OTP: code memory for cryptRISC programming. The code memory is preferably formed as a writable or rewritable nonvolatile memory (EEPROM) and receives the operating program for the processor core. As a result, the adaptation of the control module to the different required applications on consumable cartridges for different printers.
• - Data FERAM: rewritable nonvolatile data storage. FERAM memory has a particularly high memory speed and therefore allows flexible adaptation to applications with high data processing speed. As a result, even proprietary high-speed data transmission protocols, such as those used by printer manufacturers to communicate the printer with control modules on consumable cartridges, can be universally implemented.
• - Data SRAM: rewritable data store
• - CFG: configuration unit
• - TRNG: Random number generator to generate true random numbers
• - DES / 3DES: encryption unit for the encryption standards DES or 3DES. The standard crypto algorithms are provided permanently interconnected. This enables a high processing speed, in particular for cryptographic operations.
• - RC OSC: Processor Clock Oscillator
• - POR: reset at power-up (power-on-reset)
• - TEST: s test circuit

The aforementioned function blocks are via an internal bus (processor bus) 4 connected with each other.

Optionally, further functional blocks may be provided. About the contact elements ( 3 ) VDD and GND will supply the power to the circuit 2 created.

The function block SPU, in turn, with the interface IO and the bus 4 is connected to the contact element ( 3 ) SCL, via which an external clock signal is fed, as well as the contact element SDA, which serves to input data signals from the printer and output data signals to the printer (bidirectional data communication).

• – LEDN / RESN: RESET-Eingang/Ausgang, LED-Ansteuerung
• – INIT: Initialisierung
• – GPIO: Allzweckeingabe/-ausgabe (General Purpose Input-Output): Hierbei handelt es sich um frei programmierbare Ein- und Ausgänge, die zur Ein- und Ausgabe beliebiger digitaler Daten und Steuersignale konfiguriert werden können. Ferner ist es möglich, durch die angeschlossene Pulsweitenmodulationseinheit PWM quasi-analoge Signale auszugeben, beispielsweise Steuerströme für opto-elektronische Übertragungselemente (LED) oder zur Simulation von Prüf- oder Messwiderständen.

In the case of the freely programmable interface IO, some possible contact elements 3 are given by way of example:

• - LEDN / RESN: RESET input / output, LED control
• - INIT: initialization
• - GPIO: General Purpose Input-Output: These are freely programmable inputs and outputs that can be configured to input and output any digital data and control signals. Furthermore, it is possible through the connected Pulse width modulation unit PWM output quasi-analog signals, such as control currents for opto-electronic transmission elements (LED) or for the simulation of test or measuring resistors.

As a result of the freely programmable interfaces according to the invention, which in the example shown includes the function blocks IO, SPU and PWM, the cryptRISC processor core can communicate with a printer via a freely configurable interface configuration within wide limits. This allows a flexible adaptation to different printer models from different manufacturers. By using the cryptRISC processor core and the specially adapted auxiliary modules (TRNG, DES, etc.) a high data processing speed is ensured, so that an adaptation to different data transmission protocols is guaranteed, even if they require high data transmission rates or data processing speeds.

Due to the particular adaptability of a control module according to the invention 1 can be the function of a control module 100 a first printer manufacturer, as in 3 is exemplified, be modeled, or for a different control module 200 another printer manufacturer, as in 4 is shown. A special feature of the control module 200 consists, for example, that it additionally an opto-electronic element, namely a light emitting diode (LED 201 ), which can be controlled by the circuit according to the invention via a correspondingly programmed control output GPIO.

2 shows a practical embodiment of a control module according to the invention 1 , On a circuit board 5 (PCB PCB) are the contact elements 3 arranged according to the contact geometry in a printer, in which a consumable cartridge can be used.

As an example of a consumable cartridge is in 5 an ink cartridge 300 shown with a control module 1 according to 2 Is provided.

LIST OF REFERENCE NUMBERS

1

control module

2

circuit

3

contact elements

4

bus

5

 circuit board

100

control module

200

control module

201

led

300

ink cartridge

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2009/145775 A1 [0006]
• EP 1736318 A2 [0007]
• EP 2361770 [0007]
• EP 2607082 A1 [0007]

Claims (6)

Integrated electronic circuit ( 2 ) for a control module ( 1 ) for mounting on a consumable cartridge, at least comprising the functional blocks interconnected via processor bus lines: • Programmable code memory processor core • readable and rewriteable data memory • serial bidirectional interface characterized in that • the processor core is implemented as a cryptRISC processor core having a RISC processor architecture has additional cryptographic commands, and • the bidirectional interface with respect to the wiring of the contact elements ( 3 ) and the data transmission protocols used is freely programmable. Circuit ( 2 ) according to claim 1, characterized in that it comprises an oscillator (OSC) for the processor clock. Circuit ( 2 ) according to claim 1, characterized in that it comprises a random number generator (TRNG) for generating true random numbers. Circuit ( 2 ) according to claim 1, characterized in that it comprises an encryption unit (DES / 3DES). Control module ( 1 ) for a consumable cartridge characterized by a circuit ( 2 ) according to claim 1. Consumable cartridge ( 300 ), characterized by a control module ( 1 ) according to claim 4.

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