Schemes on key tablets. A simple combination lock with an analog tablet key iButton (LM339). How the One-Wire bus works

Magnetic keys This is not only daily access to the entrance, it is the so-called identifier of the person who owns such a device. Electronic code media is actively used both in security systems and in various semi-automatic engineering systems. We sometimes rarely think about where we can apply knowledge about magnetic code carriers. But more detailed knowledge sometimes helps us in life. We will try to tell you a little about magnetic keys, cards and key fobs.

There are many identifier models. Some serve as access cards to the office, others open entrance doors, others launch ventilation controls, and others open safes.

Magnetic keys and blanks for intercoms

Let us roughly divide all magnetic media into 5 categories:

1. Electromagnetic access keys

2. Access cards

3. Key rings with code

4. Magnetic bracelets

5. Active and passive tags

Magnetic keys

The most common devices in everyday life. We actively use magnetic keys and blanks for intercoms every day. We used to call them " intercom key", "tablet", "magnetic key" etc. In fact, these names do not accurately reflect the correct name. Some people really believe that such a key can " magnetize". This is also not true. Correct name - electromagnetic key or electronic identifier. And its operating principle is simple - the device itself contains non-volatile memory on which a unique identification number is recorded. Sometimes this number (code) can be changed.

Magnetic keys and blanks for intercoms are divided into 3 categories

1. Factory coded (not rewritable) . This code is assigned immediately when the key is produced. Both numbers and letters are used. There are billions of combinations of unique codes. The chance of meeting a double (double) is in hundredths of a percent. This is the cheapest option for a magnetic key. The most common model, both for entrances and in any systems.

2. Rewritable blanks . Outwardly, they are no different from their “brothers”. But they cost a little more. All because of the advanced functionality of the key. For such models you can have a code delete and write a new one. Such keys are not used very often. The main scope of application is companies engaged in the production of intercom keys for entrances.

3.Recordable blanks . Just like rewritable ones, they do not differ in design. The functionality is a little more modest - they can be recorded only once. That is, the code can be programmed once and forever. Since they cheaper of the second category (overwritten many times), then this is the key to which your " tablet from the entrance".

4. Universal . In fact interesting option he just takes away a set of ready-made keys that fit many intercoms. Eat different variants. The essence of such a set is simple - to make keys to all entrances in one bunch. The secret lies in the fact that almost all entrance intercoms produced have a sewn-in serial number, which is copied onto magnetic key in such a set. Prices universal sets different because they include different quantities magnetic tablets.

Pros and cons of magnetic keys and blanks for intercoms

The main advantages of such products are their durability and practically indestructible functionality. Made with the expectation that they will hang around for years together with the keys to the apartment, on one bunch. These can last forever. There are practically no disadvantages, except for their possibility " demagnetize"But you need very strong objects nearby (with a strong magnetic field) to damage the internal key code.

Access cards

Magnetic cards access are essentially clones of “tablets”. The principle of operation of cards is exactly the same as that of magnetic keys. There are few differences: a different design, several additional functions for some models, ease of storage.

This is useful to know about ACS:

For the full operation of many systems (including access control and management), special “electronic keys” are required. These keys have many names: access cards, tablets, key fobs, magnetic cards, identifiers, tags, key fobs, etc. But all of them are designed to recognize the visitor or user.

Identifiers can be used to access the premises, quickly arm (or disarm), confirm entered actions, and launch a specific control scenario.

Typically, the cost of cards and key fobs is not high, since they are easy to manufacture. A special feature of these additional devices is the presence of non-volatile (in in rare cases dependent) memory, which contains an electronic (alphanumeric) code. In some cases it can be changed, in some cases additional data about the key owner can be stored in memory.

Please note that electronic key duplicators are located in the "Measuring Instruments" section.

Identifiers are:

Important! Be sure to read the instructions for the device as there are several electronic key formats (TouchMemory, HID, EM-marin, MIFARE and others).

Door opening buttons are:

Beautiful design solutions for the execution of door opening buttons on the market a large number of. Now there are wireless buttons, touch-sensitive, and piezoelectronic. But the most reliable, as always, are buttons with mechanical metal filling. Such buttons are not afraid of temperature changes and moisture. We invite you to view and purchase any door opening buttons (locking, remote, illuminated) in our online store.

What are the opening buttons?

• Normally open
• Normally closed
• Combined (open/closed)
• With backlight (LED)

The specialists of the ABars systems protection company will be happy to select for you additional equipment for an access control system for any type of facility.

Buy and order delivery of buttons and cards in Moscow:

You can order and buy all these products through the online access control store of our website or order delivery or professional installation in Moscow from the ABars company (when purchasing cards, keys or buttons for an amount over 8 thousand rubles, delivery is free).

If you find it difficult to choose the desired card format or have other questions about the characteristics, call our company.

Recently arrived, but firmly established in everyday life, intercoms are deservedly popular among the capital's residents. In the bustle of the metropolis, it is important to maintain the safety of personal space, maintain cleanliness, order, and silence in the house. A high-quality intercom is not only a reliable device and a handset with good audibility, but also a practical tablet key that will not let you down at a crucial moment. Manufacturing keys for tablets is one of the main areas of work of our company.

Types of intercom keys

Intercoms differ greatly in design and purpose. There are audio and video intercoms, and the latter can be equipped with either a monochrome or color display. Digital and coordinate matrix, small and multi-subscriber intercoms are distinguished by the same variety of unlocking devices. The most common of them are key tablets in Moscow, which almost every capital resident has. In general, there are several types of unlocking devices, duplicates of which can be made in our workshop.

• Contactless electronic cards.
• Radio-controlled magnetic key fobs.
• Keys are made by different companies: Metacom, DALLAS, CYFRAL, ELTIS, VIZIT.
• It is possible to reprogram the keys of the tablets.

How magnetic tablets work

Keys for intercoms are united by the principle of operation. Each duplicate tablet key sends a signal to the reader, which processes the information received in a matter of seconds and unlocks the door. A special code is applied during manufacture. If you need to make a new tablet key, you just need to read the information from the original provided and apply it to a clean blank. However, the task, which takes only a few minutes, requires professional knowledge, because each manufacturer has its own way of encoding keys.

• The manufacturer applies an individual code to the chip.
• To read the code you need special equipment.
• Duplicates are ready for use immediately after chipping.
• It is possible to replicate any number of tablets from one original.
• Programming one key takes about 30 seconds.

Why is it profitable to order a tablet key from our company?

Our workshop is well known to residents of the capital - thousands of Muscovites have our intercom keys on their bundles, which, judging by the reviews of regular customers, work flawlessly in any conditions. The quality of the tablet key, the price of which is quite reasonable and about 10% lower than the Moscow average - main reason the fact that engineers and entrepreneurs, doctors and teachers from all metropolitan areas come to our company. They are confident that our keys, made to the highest standards, will not fail under any circumstances.

• We will produce any number of tablets for a family or for the entire entrance.
• Low prices and regular discounts will become pleasant surprise for clients.
• We are located in the very center of the capital, there is convenient parking.
• We cooperate with individuals, commercial and municipal organizations.
• A guarantee is provided with the right to free recoding.

It is not difficult to order tablet keys in the capital - almost every workshop will undertake their production. The question is how long the product will last, whether it will break during operation, or whether it will decode during intensive use. By contacting the World of Keys company, you get rid of the need to wait for a representative of the company that installed the intercom, and you will receive high-quality tablets in the shortest possible time. We are proud that when the need arises again, customers come back here again and recommend the workshop to family, friends, and colleagues: keys made using modern equipment will serve faithfully for many years.

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This device consists of two parts that are “tailored” to each other. The first is the Dallas Touch Memory key, which is programmed once and contains non-volatile memory. The second is the counter part - an electronic adapter board that generates output signals to the main device in accordance with the firmware. Exist various options such devices, but their operating principle is similar.

Below we discuss the device, operating principle and configuration of the 24V2 electronic lock, which has proven itself and is widely used in gaming and vending machines.

The 24V2 electronic lock has been specially designed to replace electromechanical locks that are used in entertainment equipment. Its development was due to several disadvantages of the above-listed locks: problems with purchasing locks “one key”, which led to the installation of locks with different keys in one establishment and complicated the work of cashiers-operators, low durability and low security, which led to unauthorized setting up loans for equipment.

All these shortcomings and extensive experience in this field were taken into account when developing the 24V2 electronic lock. The geometric dimensions were also preserved, which allows for quick installation electronic lock directly to the place of the electromechanical one. It became possible to replace up to three electromechanical locks with one electronic one in cases where this was required by the specifics of the equipment used (setting, draining, statistics). Moreover, the use of one electronic key to control all three channels of the lock (hold, touch, double touch) is also original.

The method of registering keys in locks is also unique, which does not require additional equipment, and in case of loss of one of the keys used, it allows you to quickly change the code on all the locks of the establishment on the spot. It should be noted that Touch Memory (iButton) Dallas DS-1991L is used as keys, which, by using a shared method of generating and storing the code, completely excludes its unauthorized reading or cloning of the key. This choice is confirmed by the uninterrupted operation of a huge number of locks in various regions of Russia for more than three years.

1. Description of the electronic lock.

The lock is powered by a stabilized voltage of +5 volts. Since the current consumption is quite small and is approximately 8 mA, it can be connected directly to the power supply of the equipment where it is installed. The connection of power, ground and controlled channels is carried out using screw terminal blocks in accordance with the figure, which, in combination with a threaded contactor, with the help of which the lock is attached to the equipment body, reduces installation time by an order of magnitude.

The lock can be in one of two modes: “Operation” and “Service”.

2. Description of the “Operation” mode.

The “Operation” mode is the main mode for the electronic lock. When power is supplied to the lock, it blinks the built-in LED, indicating the installed configuration (all locks are supplied with configuration 1) and enters the “Operation” mode. If you hold down the “Service” button while applying power, the LED will blink to show the version software(hereinafter referred to as software).

In the “Operation” mode, the lock reacts to three, possible options interactions with the electronic key (hereinafter simply the key), which are indicated by the built-in LED:

1. Pressing and holding the key in the contactor (LED blinks once).

2. Touch the contactor with the key once (LED blinks twice).

3. Touch the contactor with the key twice (the LED blinks three times).

Depending on the selected configuration, the lock's reaction to the listed interactions with the key may be different.

Attention! Starting from the lock software version V3.2 and higher, when power is applied to it, it tests the state of the contactor for a short circuit, indicating a defect by frequent blinking of the LED.

Pressing and holding the key in the contactor activates channels 1 and 2, and appears on them. low level(LED will blink 1 time). When the key is removed from the contactor, they go into a high-impedance state.

When you touch the contactor twice with the key, channels 1 and 3 go into trigger mode, a low level appears on them (the LED will blink 3 times). To enter the high-impedance state, you must touch the contactor with the key one more time.

This configuration is most appropriate to use in equipment on the Novomatic platform or a similar one, when replacing one electromechanical lock. In this case, the signal wire is connected to channel 1, channel 2 can be used to connect a 5 volt buzzer as an alarm if needed, and channel 3 is not used.

Since the Novomatic platform is the most popular, all locks are supplied with a pre-installed configuration 1.

Pressing and holding the key in the contactor activates channels 1 and 2, a low level appears on them (the LED will blink 1 time). When the key is removed from the contactor, they go into a high-impedance state.

When you touch the contactor twice with the key, a low level appears on channel 3 lasting 0.5 seconds (the LED will blink 3 times), then the channel returns to the high-impedance state.

This configuration can be used in equipment that uses the Igrosoft platform or a similar one when replacing two electromechanical locks. In this case, the credit setting signal wire is connected to channel 1, channel 2 can be used to connect a 5 volt buzzer as an alarm if needed, and the short ledger signal wire is connected to channel 3.

Pressing and holding the key in the contactor activates channel 1, a low level appears on it (the LED will blink 1 time). When the key is removed from the contactor, it goes into a high-impedance state.

When you touch the contactor once with the key, a low level appears on channel 2 for 0.5 seconds (the LED will blink 2 times), then the channel returns to the high-impedance state.

When you touch the contactor twice with the key, channel 3 goes into trigger mode and a low level appears on it (the LED will blink 3 times). To enter the high impedance state, you must touch the contactor again.

This configuration can be effectively used in equipment on the Belatra platform or similar, when replacing three electromechanical locks. In this case, the credit setting signal wire is connected to channel 1, the credit withdrawal signal wire is connected to channel 2, and the short ledger signal wire is connected to channel 3.

Configuration 4 “Classic”.

Functionally, it is similar to the Belatra configuration. The difference is that there is a delay in the activation of channel 1 when the key is held in the contactor and there is no appearance of a low level for 1 second on this channel during the other two possible interactions of the key and the contactor. This is an emulation of the operation of locks with previous software versions below V3.1, in which the operating algorithm was different and it was not possible to select a configuration.

The configuration was left for convenience collaboration locks with different software versions in one establishment.

Configuration 5 “Trigger”.

The configuration was added in lock software versions V3.3 and higher.

When you touch the contactor once with the key, channels 1, 2 and 3 go into trigger mode, a low level appears on them (the LED will blink 3 times). To switch them to a high-impedance state, you need to touch the contactor again.

3. Description of the “Service” modes.

Service modes are intended for registering working keys and selecting the configuration of the lock.

The lock has four service modes. To enter the corresponding service mode, you must enter its number using the “Service” button (hereinafter simply the button). Input is carried out by sequentially pressing and holding until the press is confirmed by the LED indication (about 1 second), and releasing the button the required number of times in accordance with the service mode number. After entering the service mode number, the lock confirms entry into it with the corresponding number of LED blinks.

"Mode 1"— the lock remembers the password from the “open” key pressed to the contactor.

Successful reading and memorization of the password from the “open” key by the lock is confirmed by the LED blinking once and returning to the “Operation” mode. To exit the mode, you must press the button once, or pause for 30 seconds.

"Mode 2"— generating a random password and writing it into the keys pressed to the contactor.

All keys pressed to the contactor, but no more than 7, are cleared and a new password is written into them. Each successful operation confirmed by the LED blinking twice. The keys become “open” and can only be used to transfer the password, both to the memory of the lock being used and to the memory of other locks of this group through service mode 1. To exit the mode, you must press the button once, or pause for 30 seconds.

"Mode 3"- locking keys.

All “open” keys pressed to the contactor are “closed” and become “working”. Each successful operation is confirmed by the LED blinking three times.

To exit the mode, you must press the button once, or pause for 30 seconds.

Attention! If the LED blinks frequently when you apply the key, this indicates an error, which may be caused by poor contact between the key and the contactor. In this case, it is necessary to clean the contactor and repeat the operation.

"Mode 4" - selecting the lock operation configuration (was added in lock software versions V3.1 and higher).

After entering the mode, you can select the required configuration of the lock. The selection is made by sequentially pressing and holding until the press is confirmed by the LED indication (about 1 second), and releasing the button the required number of times in accordance with the configuration number. After finishing entering the configuration number, the lock confirms the selection with the corresponding number of LED blinks and enters the “Operation” mode.

1- Novomatic configuration.

2- Igrosoft configuration.

3- Belatra configuration.

4- “Classic” configuration.

5- “Trigger” configuration.

A description of the lock's operation when choosing different configurations is given above.

Attention! The installed configuration is indicated by blinking of the LED when power is applied to the lock.

Since equipment on the Novomatic platform is most in demand, locks are supplied with configuration 1.

4. Method of registering electronic keys:

After installing and connecting the lock according to Figure 1, it is necessary to carry out the procedure of generating a new password, transferring it both to the memory of the lock being used and to the memory of other locks of this group and creating “working” keys. The procedure for carrying out the procedure is given below.

1. It is necessary to supply power to the lock, and the LED will blink to show the current configuration of the lock (see point 2).
2. According to paragraph 3, enter service mode 2 and, by pressing the keys against the contactor, create the required number of “open” keys. The keys must be pressed sequentially at intervals of no more than 30 seconds.
3. Exit the mode by briefly pressing the button or pausing for 30 seconds.
4. According to clause 3, enter service mode 1 and, by pressing any of the keys created in clause 4.2, transfer the password to the lock’s memory. The LED will blink once to confirm the successful completion of the procedure. The lock is ready for use. This procedure must be carried out with all locks in the group.
5. On any of the locks, enter service mode 3, according to clause 3, and by pressing the “open” keys created in clause 4.2 to the contactor, close them. The keys must be pressed sequentially at intervals of no more than 30 seconds. Thus, we will receive “working” keys to which all locks in the group will respond according to the established configuration in step 2.

Some people think that simple magnets are installed in intercom keys that open the door during contact with the lock. This is a fairly common misconception. In reality, the tablets are ROMs that have a hardcoded ID inside them. This type of memory is called Touch Memory.

The tablet communicates with the intercom using the One-wire bus - this is a single-wire interface. This bus was developed by the Dallas company; it can be used to communicate with several devices using one wire. If the device is passive, then the bus transmits power through one conductor.

The photo shows the internal composition of the key

The tablet contains a 60 picofarad capacitor, which provides short-term power during the response period. The master device constantly generates a single signal to charge the above-mentioned capacitor so that the ROM can be safely powered.

Everything that is needed for the normal operation of the identifier is transmitted using one wire. The 1-Wire bus turned out to be so successful that entire industrial networks are organized using it.

What are the operating principles of the device?

Factories producing intercom systems independently produce copies with unique, non-repeating codes. During the installation of an intercom device, the installation company registers all products in the system memory. Every time the key is brought to a special reader, the device checks its information with that stored in the intercom controller. If the code in the controller memory and the key matches, then the door will open.

Many intercoms have a lot of free memory, the symbols of which also contain a key. By checking the product code information, the intercom device identifies it as stored in memory, then opens the door.

The universal key contains certain information that the intercom reads while in normal mode.

When a universal tablet is used, all operations are performed a few seconds slower than when reading original products. In this case, the panel screen displays the following information: OPEN, BAXTA, FL355, FL256, ERROR-OPEN, —, -_. Such instances are universal for all intercoms.

The operation of such devices does not depend on the intercom, the country or city in which it is installed, or on the company that installs and maintains intercoms. The principle of its operation is similar to ordinary keys. The only difference is that regular ones can only open one lock, while a universal one can open thousands.

However, it is advisable to have the right kit. A universal key is good, but it alone may not be enough for all intercoms that exist in big cities.

The video shows a demonstration of how the universal key works:

Why do you need a full set of keys?

To be able to open absolutely all doors, you need to have a complete set, which includes different products:

• Four tablets;
• A pair of radio tags;
• Two-pin key.

This kit has many different identifiers, even for new RFID devices, as well as a regular key that works with two-pin devices.

Nowadays you can find intercoms or electronic locks using Touch Memory technology everywhere. Many people use regular IDs to get into their home. In order not to carry several different tablets, in addition to standard products for mechanical locks, it is worth using a universal identifier that opens any intercom.

It is not necessary to have a whole set if there is no special need.

By purchasing a universal key, you can get rid of unnecessary problems. You no longer need to stand and freeze under the door or spend a long time remembering the apartment number of the friends you came to visit. There is no need to spend money from your mobile phone on calls to ask relatives or friends to open the entrance. Universal keys can open many intercoms.

People of many professions need not just one key, but the whole set. It will come in handy:

• Direct marketing and advertising agencies, which have their own materials distribution service;
• Courier delivery services;
• Marketing and sociological services that engage in door-to-door surveys of the population;
• Newspaper delivery boys and postmen;
• Advertising distributors;
• Private entrepreneurs;
• Housing and communal services workers;
• Internet providers.

A solution from several is needed, because some manufacturers use different systems. In general, universal keys are a means of official access to intercoms provided by manufacturers.

The video shows information on how to program the intercom key: