Failure of a key is a very rare phenomenon if we consider the so-called tablets, and very likely if we are talking about a contactless RFID system built on cards triggered from a long distance.

If for some reason the entrance door, the gate of a private house or the lock at work no longer unlocks, the question often arises: how to reprogram the key to the intercom? For the average user, this process does not mean complex intervention and participation in programming a personal identification device.

Features of programming intercom keys

To understand why programming individual intercom keys only involves recording a new identifier and linking it to the subscriber on the device installed in the door, it is worth paying special attention to the mechanics of operation and the internal structure of the usual tablets and cards.

All keys are built on a one-time device circuit. If a failure or physical violation of the internal structure occurs, the personal identifier is simply thrown away or destroyed. Neither repair nor reprogramming without the use of special industrial devices is provided.

RFID

Small keychains and cards are already familiar to many people. For such a key to operate, it does not need to be leaned against the reading pad. You just need to bring it a certain distance.

The keys are ranked according to their operating range:

1. with an identification zone of 100-150 mm, common format, Proximity type;
2. with a detection range of up to 1 m, Vicinity type.

Despite such differences in range, all identifiers work according to a simple scheme.

An intercom using keys of this class has a low-intensity electromagnetic field radiation unit in the contact area. Inside an RFID card or key fob there is a simple circuit; it includes an inductive oscillating circuit, a miniature transmitting antenna and a chip that generates a signal.

When the key is brought into the radiation zone, energy is generated and the internal electrical circuit is activated. The card or key fob transmits a radio frequency signal, the intercom recognizes the identifier and unlocks the door if it is registered in its memory.

There is simply no simple way to reprogram an RFID-class intercom key for most types of products. The identifier is formed by a factory-sprayed chip, the number of unique combinations (cards and key fobs) is huge, changes to the code are not provided.

The key can deteriorate either due to mechanical kinks or breaks (as a result, damage to the chip or transmitting antenna grid occurs), or due to exposure to strong electromagnetic radiation, comparable in strength to a microwave oven.

Touch-Memory

Touch-Memory is the contact tablet most people are familiar with. There is also a microchip inside this key.

However, the identifier is transmitted via a single-channel electrical circuit. When the key is applied to the contact pad, the data reading circuit is closed in the intercom.

A unique code stitched into the tablet is transmitted and checked against one of those stored in the device’s memory. If identification is successful, the door will unlock.

A Touch-Memory tablet can be damaged by exposure to strong static voltage by applying the tablet to electrified clothing. This is quite difficult to do, since the pulse must pass between certain points of the contact pad, but this is the most common cause of breakdowns.

The tablet with the chip is very durable, it is difficult to damage it mechanically, the key is that, in addition to exposure to static, it can be burned in the microwave. Touch-Memory tolerates any other influences, including the most powerful neodymium magnets, without consequences.

The way to program access keys for an intercom of this class is to use a special programmer. It is used to make clones of tablets, as well as universal master keys for a series of intercoms.

Touch-Memory is divided into classes. They depend not on the internal structure and principles of operation, but on the manufacturers, each of whom creates an internal circuit with certain characteristics and a methodology for generating a unique code.

The following types of Touch-Memory are widely used:

• with markings starting with DS (Dallas), used in a huge number of models Vizit, Eltis, C2000 and others;
• marked DC, as well as Cifral KP-1 - Touch-Memory data is intended only for Cifral intercoms;
• K series, widely used in Metacom access control systems and other intercoms.

Similarly, there are classes and RFID formats, for example, the oldest HID, the popular EM-Marin, and also used in Mifare cards triggered from a long distance. Therefore, before figuring out how to program a personal key for an intercom from an entrance door, you first need to purchase a Touch-Memory or RFID compatible format.

Do-it-yourself intercom key programming

The method for encoding a personal key for an intercom from work, home or friends' entrance consists only of recording the data of the corresponding personal identifier into the memory of the device controlling the door. To do this yourself, you need to access the service functions from the front panel keypad.

The technicians who install the intercom are required to reprogram and change the factory master codes and other service information of the device.

If this is done, the methods for registering your key in the intercom using standard access combinations will not work. However, a huge number of devices on the door respond to factory codes and allow you to activate service functions.

Algorithm of actions

The easiest way is to find out how to encode the key for the intercom from the entrance door from a service company. Some of them provide such data.

But there is a set of standard actions for intercoms of common brands.

1. Rainmann, Raikman - press call, enter 987654, after the beep - 123456. If the invitation P appears on the display - press 2, apply the tablet, press #,<номер квартиры>, #. Recording into memory is done with the * button;
2. — dial #-999, after the invitation sound, dial code 1234 (for some series - 6767, 0000, 12345, 9999, 3535). After this, press 3, after a pause - the apartment number, apply the key, press #, *. If the factory code (1234 and others) is not accepted, the intercom will emit a two-tone signal;
3. , - hold the call button until there is a reaction (sound, invitation on the display), enter 1234, then the apartment number, call. In response to the invitation to place the key, exit the menu by pressing the * button.

The most modern versions of the Cifral intercom use fairly complex code sets. The method for encoding the key to the intercom from the entrance door looks like this: call, 41, call, 14102, 70543.

Then you should wait for the invitation to appear on the screen, press 5, enter the apartment number, after the inscription on the Touch display, attach the key. A sound signal indicates recording into memory.

Conclusion

You can record any of the purchased keys, which are mistakenly called blanks, into the intercom memory. In reality, it is a working mechanism with its own unique code. It only needs to be registered at the entrance device.

A variety of key application techniques are available. The same one can be used on several intercoms of the same brand, provided that registration has been made on each one. The main thing is that the Touch-Memory tablet or RFID card or key fob must have a format compatible with the device on the door.

Video: How to duplicate an intercom key

Intercom key copier

Intercom key copier

Join our Facebook group: https://www.facebook.com/groups/463937897339644

About two years ago, as part of a series of publications about copying electronic keys, it was posted, developed by Recto- member of the forum of the site Kazus.ru.

Since then, the project has received further development - both in terms of the element base and in terms of the functions performed. Today, it is in no way inferior to industrial designs that perform similar tasks. But unlike industrial products, which also cost a lot of money, the Recto copier is an open source project and even novice radio amateurs can assemble it, provided that they have the opportunity to flash the microcontroller. However, now this is not such a problem. But in the end, you will get a device that can make a copy of almost any electronic key for an intercom or other access control device. The proposed copier (duplicator) allows you to read and write almost all currently existing “intercom” contact keys (Touch Memory) formatsDallas -1990, A Metacom And Cyfral . Recording to blanks is supported: TM-2004,TM-08,TM-08v2,RW-1990,RW-1990.1,

RW -1990.2 and TM-01.

1. In addition to the main functions mentioned above, the device allows you to:

2. Fully work with the key database - it is possible not only to read, but also to save and delete entries in the database by the copier itself.

3. Perform various operations with the buffer - edit, create and compare keys.

4. Enable/disable CRC control mode. Disabling this mode allows you to read and write any Dallas keys, incl. having an incorrect CRC.

5. Software power off.

The device is controlled through the menu. All functions have a simple, intuitive interface and are provided with tips. The new version runs on microcontrollers PIC 16F 648Dallas -1990 or PIC 16F 88, both firmware versions are included in the project archive.

Description of the scheme.

A special feature of this device is that it can be assembled as minimum, and in full configuration using the same firmware. The minimum configuration assumes that the device will be used without an LCD display, and all information will be displayed on three LEDs (Fig. 1).

Rice. 1

In this case, it is only possible to read the keys, determine their type and write the code to the blank.

A description of the minimum configuration is given in a separate file, then we will talk about the fully functional version of the device, the circuit diagram of which is shown in Fig. 2

Rice. 2

LEDs You can use any colors, the proposed scheme is only a recommendation. But for convenience of presentation, the description of the signals will be given in accordance with this diagram.

Red (HL 1) - power indicator " POWER", as well as a low battery indicator. If the device has a low-voltage detector, then when it is triggered, the indicator begins to glow intermittently.

Yellow (HL 2) - designated as " READ", gives a signal that the key has been read. Lights up and stays lit if there is a key in the device’s memory. If the indicator is not lit, it means that the key is not in memory.

Green (HL 3) - designated as " WRITE", in recording mode signals the end of the process. At the same time, if the indicator is lit with normal light, the recording was successful, and if it flickers, there is an error. In reading mode, this LED indicates each key reading with short flashes.

Any LCD indicator can be used as a display 16x2 controller based HD 44780 with a Russified character table, or compatible with it. In the author's version, for example, a display was used FDCC1602B-FLYYBW-51LR. You can, of course, use the display without the “Cyrillic” alphabet; taking into account this option, “adapted” firmware with messages in English is attached to the project archive.

The full configuration printed circuit board has 4 holes for mounting the display, the distance between the holes is 80 x 31 mm. There is no special connector for the display, since there are quite a few display designs, and each has its own pin arrangement. The display is connected to the board using a small harness or cable, which is soldered to the labeled contacts on the board.

Some parts marked with an asterisk in the diagram will require selection for specific conditions. Firstly, the value and power of the resistor R 9, which limits the display backlight current, is selected individually for each specific display. For example, my display required a resistor of about 10 ohms.

Secondly, the divisor R 10-R 11 are selected according to the optimal level of image contrast on the display. Approximate values ​​of these resistances are shown in the diagram. In principle, you can replace this divider with one variable resistor.

And finally, if a low battery detector is used, a resistor will need to be selected R 4 and zener diode VD 2. With the ratings indicated in the diagram, the detector is triggered when the voltage drops below 4.7 volts. However, before soldering into the board, it is advisable to select these parts on a breadboard in order to set the response threshold that you specifically need. The detector parts must be selected so that the voltage changed directly at the zener diode is about 4.2 volts (with normal power supply at the device input). That is, it should be approximately 0.5 volts below the selected threshold of the detector.

Battery monitoring and LCD power management are optional features that can be disabled if the device is powered by a stationary source. In this case, if the power detector is excluded from the circuit, it is necessary to apply the log level. " 1 » to the entrance A5(leg 4) so ​​that the MK always “sees” a full battery. When using only my firmware in the device, you can simply connect the legs 4 Metacom 2 between themselves. This situation is monitored by software, so the detector will not trigger falsely when you press the button. S 1 will not happen.

To block the power management function, instead of a transistor, you need VT 1 place a jumper, closing the collector-emitter terminals (if you use the proposed signet for the full configuration). And to the conclusion 15 MK(line A6) it is necessary to submit the log level. “0” so that the MK does not enter sleep mode due to a timeout. In principle, you can simply connect this pin to ground. However, for reliability, it is advisable to do this through a resistor with a resistance of several kilo-ohms.

Each intercom key has its own number - it is this number that serves as the key identifier. It is by the key number that the intercom decides whether it is yours or someone else’s. Therefore, the copying algorithm is as follows: first you need to find out the number of the allowed key, and then assign this number to another key - the clone. It makes no difference for the intercom whether the original key or a copy was attached. After checking the number against his database of authorized numbers, he will open the door.

Intercom keys that we will connect to Arduino (they are sometimes called iButton or Touch Memory), are read and written via single-wire 1-wire interface. Therefore, the connection diagram is very simple. We only need a couple of wires and a 2.2 kOhm pull-up resistor. The connection diagram is shown in the figure.

The assembled circuit might look something like this:

2 Reading iButton Key ID using Arduino

There are ready-made libraries for Arduino to work with the 1-wire interface. You can use, for example, this one. Download the archive and unpack it into a folder /libraries/, located in the Arduino IDE directory. Now we can work with this protocol very simply.

Let's upload this sketch to Arduino in the standard way:

OneWire iButton(10); // create a 1-wire object on pin 10 void setup (void) ( Serial.begin(9600); ) void loop(void) ( delay(1000); // delay 1 second byte addr; // array for storing key data if (!iButton.search(addr)) ( // if the key is not attached Serial.println("No key connected..."); // report this return; // and interrupt the program ) Serial.print("Key: ");

for(int i=0; i ) This sketch shows the key number for the intercom, which is connected to the circuit. This is what we need now: we need to find out the number of the key we want to make a copy of. Let's connect the Arduino to the computer. Let's start the serial port monitor: Tools Serial Port Monitor

(or the keyboard shortcut Ctrl+Shift+M). Now let's connect the key to the circuit. The port monitor will show the key number.

Let's remember this number.

The figure, of course, does not show all the implementation details. Therefore, at the end of the article I attach a timing diagram in *.logicdata format, taken using a logic analyzer and program Saleae Logic Analyzer and revealed to her. The program is free and can be downloaded from the official Saleae website. To open the *.logicdata file you need to run the program, press Ctrl+O or in the menu Options(located at the top right) select item Open capture/setup.

3 Dallas Key ID Record using Arduino

Now let's write a sketch to write data to the iButton key memory.

Sketch of writing an iButton key using Arduino(expands) #include // connect the library const int pin = 10; // declare the pin number OneWire iButton(pin); // declare the OneWire object on the 10th pin // key number that we want to write to the iButton: byte key_to_write = ( 0x01, 0xF6, 0x75, 0xD7, 0x0F, 0x00, 0x00, 0x9A ); void setup(void) ( Serial.begin(9600); ) void loop(void) ( pinMode(pin, OUTPUT); delay(1000); // delay for 1 second iButton.reset(); // device reset 1-wire delay(50); iButton.write(0x33); // send the "read" command byte data; // array for storing key data iButton.read_bytes(data, 8); // read the attached key data, 8x8=64 bits if (OneWire::crc8(data, 7) != data) ( // check the checksum of the attached key Serial.println("CRC error!"); // if the CRC is not is correct, report this return; // and interrupt the program) if (data & data & data & data & data & data & data & data == 0xFF) ( return; // if the key is not attached to the reader, interrupt the program and wait , while it will be attached) Serial.print("Start programming..."); // start the process of writing data to the key for (int i = 0; i ) // Initialize writing data to the iButton key: }

void send_programming_impulse() ( digitalWrite(pin, HIGH); delay(60);

digitalWrite(pin, LOW);

delay(5); digitalWrite(pin, HIGH); delay(50); Don't forget to set the number of your original key in the array key_to_write

which we learned earlier.(expands) delay (200); iButton.skip(); iButton.reset(); iButton.write(0x33); // reading the current key number Serial.print("ID before write:"); for (byte i=0; i<8; i++){ Serial.print(" "); Serial.print(iButton.read(), HEX); } Serial.print("\n"); iButton.skip(); iButton.reset(); iButton.write(0xD1); // команда разрешения записи digitalWrite(pin, LOW); pinMode(pin, OUTPUT); delayMicroseconds(60); pinMode(pin, INPUT); digitalWrite(pin, HIGH); delay(10); // выведем ключ, который собираемся записать: Serial.print("Writing iButton ID: "); for (byte i=0; i<8; i++) { Serial.print(key_to_write[i], HEX); Serial.print(" "); } Serial.print("\n"); iButton.skip(); iButton.reset(); iButton.write(0xD5); // команда записи for (byte i=0; i<8; i++) { writeByte(key_to_write[i]); Serial.print("*"); } Serial.print("\n"); iButton.reset(); iButton.write(0xD1); // команда выхода из режима записи digitalWrite(pin, LOW); pinMode(pin, OUTPUT); delayMicroseconds(10); pinMode(pin, INPUT); digitalWrite(pin, HIGH); delay(10); Serial.println("Success!"); delay(10000);

Here's the function writeByte() will be as follows:

int writeByte(byte data) ( int data_bit;<8; data_bit++) { if (data & 1) { digitalWrite(pin, LOW); pinMode(pin, OUTPUT); delayMicroseconds(60); pinMode(pin, INPUT); digitalWrite(pin, HIGH); delay(10); } else { digitalWrite(pin, LOW); pinMode(pin, OUTPUT); pinMode(pin, INPUT); digitalWrite(pin, HIGH); delay(10); } data = data >for(data_bit=0; data_bit

> 1;

) return 0; ) It is pointless to show a time diagram of the operation of the key identifier recording sketch, because It's long and won't fit in the picture. However, I attach the *.logicdata file for the logic analyzer program at the end of the article.

Intercom keys come in different types. This code is not suitable for all keys, but only for RW1990 or RW1990.2. Programming keys of other types may lead to key failure! If desired, you can rewrite the program for a different type of key. To do this, use the technical description of your key type (datasheet) and change the sketch in accordance with the description.

Download datasheet for iButton keys

4 can be found in the appendix to the article. By the way, some modern intercoms read not only the key identifier, but also other information recorded on the original key. Therefore, it will not be possible to make a clone by copying only the number. You need to completely copy the key data.

Description of single wire

• 1-Wire interface
• Let's take a closer look at the One-wire interface. In organization, it is similar to the I2C interface: it must also contain a master device that initiates the exchange, as well as one or more slave devices. All devices are connected to one common bus. iButton devices are always slaves. The master most often is a microcontroller or PC. The data transfer rate is 16.3 kbit/sec. The bus in the idle state is at logic "1" (HIGH). This protocol provides only 5 types of signals:
• reset pulse (master)
• presence impulse (slave)
• writing bit "0" (master)

writing bit "1" (master) read bit (master)

With the exception of the presence pulse, everything else is generated by the master. The exchange always occurs according to the following scheme:

1) Initialization 2) Commands for working with ROM 3) Commands for working with PROM 4) Data transfer.

2) Commands for working with ROM

If a confirmation signal does not arrive after the initialization pulse, the master repeats the bus poll. If the confirmation signal has arrived, the master understands that there is a device on the bus that is ready for exchange, and sends it one of four 8-bit commands to work with ROM:

(*) By the way, there are quite a few families of iButton devices, some of them are listed in the table below.

iButton device family codes(turns around)

Family code	iButton devices	Description
0x01	DS1990A, DS1990R, DS2401, DS2411	Unique serial number-key
0x02	DS1991	Multi-key, 1152-bit secure EEPROM
0x04	DS1994, DS2404	4 kB NV RAM + clock, timer and alarm
0x05	DS2405	Single addressable key
0x06	DS1993	4 kB NV RAM
0x08	DS1992	1 kB NV RAM
0x09	DS1982, DS2502	1 kB PROM
0x0A	DS1995	16 kB NV RAM
0x0B	DS1985, DS2505	16 kB EEPROM
0x0C	DS1996	64 kB NV RAM
0x0F	DS1986, DS2506	64 kB EEPROM
0x10	DS1920, DS1820, DS18S20, DS18B20	temperature sensor
0x12	DS2406, DS2407	1 kB EEPROM + dual-channel addressable key
0x14	DS1971, DS2430A	256 bits EEPROM and 64 bits PROM
0x1A	DS1963L	4 kB NV RAM + write cycle counter
0x1C	DS28E04-100	4 kB EEPROM + dual-channel addressable key
0x1D	DS2423	4 kB NV RAM + external counter
0x1F	DS2409	Two-channel addressable key with the ability to switch to the return bus
0x20	DS2450	Four-channel ADC
0x21	DS1921G, DS1921H, DS1921Z	Thermochronous sensor with data acquisition function
0x23	DS1973, DS2433	4 kB EEPROM
0x24	DS1904, DS2415	Real time clock
0x26	DS2438	Temperature sensor, ADC
0x27	DS2417	Real time clock with interruption
0x29	DS2408	Bidirectional 8-bit I/O port
0x2C	DS2890	Single channel digital potentiometer
0x2D	DS1972, DS2431	1 kB EEPROM
0x30	DS2760	Temperature sensor, current sensor, ADC
0x37	DS1977	32 kB password protected EEPROM
0x3A	DS2413	Dual Link Addressable Switch
0x41	DS1922L, DS1922T, DS1923, DS2422	High resolution thermochronic and hygrochronic sensors with data acquisition function
0x42	DS28EA00	Digital thermometer with programmable resolution, serial mode, and programmable I/O ports
0x43	DS28EC20	20 kB EEPROM

Data is transmitted sequentially, bit by bit. The transmission of each bit is initiated by the master device. When recording, the presenter lowers the line to zero and holds it. If the line holding time is 1…15 μs, then the “1” bit is written. If the holding time is 60 μs or higher, bit “0” is written.

Reading bits is also initiated by the master. At the beginning of reading each bit, the master sets the bus low. If the slave wants to send a "0", it holds the bus in the LOW state for a time from 60 to 120 μs, and if it wants to send a "1", then for about 15 μs. After this, the slave releases the line, and due to the pull-up resistor it returns to the HIGH state.

For example, this is what the timing diagram of the Search ROM (0xF0) search command looks like. The bit write commands are marked in red in the diagram. Pay attention to the order of the bits when transmitting over 1-Wire: the most significant bit is on the right, the least significant bit is on the left.

3) Commands for working with EEPROM

Before considering the commands for working with the iButton PROM, it is necessary to say a few words about the dongle memory structure. The memory is divided into 4 equal sections: three of them are intended to store three unique keys, and the fourth is for temporary data storage. This temporary buffer serves as a kind of draft where data is prepared for writing keys.

There are 6 commands for working with EPROM:

Name	Team	Purpose
Write to temporary buffer (Write Scratchpad)	0x96	Used to write data to a temporary buffer (scratchpad).
Read from temporary buffer (Read Scratchpad)	0x69	Used to read data from a temporary buffer.
Copy from temporary buffer (Copy Scratchpad)	0x3C	Used to transfer data prepared in a temporary buffer to the selected key.
Write Password	0x5A	Used to record the password and unique identifier of the selected key (one of three).
Write SubKey	0x99	Used to directly write data to the selected key (bypassing the temporary buffer).
Read key (Read SubKey)	0x66	Used to read the data of the selected key.

4) Data transfer

To be continued...

5 Possible mistakes when compiling the sketch

1) If an error occurs when compiling the sketch WConstants.h: No such file or directory #include "WConstants.h", then, as an option, follows in the file OneWire.cpp replace the first block after the comments with the following:

#include #include extern "C" (#include #include }

2) If an error appears during compilation class OneWire has no member named read_bytes, then find and try to use another library for working with the OneWire interface.

Good day to all!
I would like to present to your attention a duplicator (copier) of intercom keys.
The copier can read/write to a key fob or card.
I have long wanted to try an inexpensive device for copying intercom keys. And now this moment has come, so let's get started.

The order arrived in 3 weeks.

Intercom keys. A small educational program.

The keys are:

• Contact. Official name Touch memory (abbr. TM) or iButton

(i.e. they must be applied to the reader)
These include:

Dallas.

In most cases, TM refers to a Dallas family key (for example, DS1990A). Many devices work with these keys: Vizit, Eltis, Z-5R, S2000-2, etc.

Cyfral.

These intercoms only work with DC2000A and Tsifral-KP1 keys.

Metakom.

K1233KT2 keys have been developed for these intercoms. These keys are also suitable for many other controllers.

Resistive.

There are exotic intercoms that work with resistive keys. Instead of a code, resistance is read from them. Without a doubt, these are contact keys, but I would not call them Touch memory.

• Contactless. The official name is RFID.

(they just need to be brought to the reader at a distance of 2-3 cm).

Available in the form of cards, key rings, bracelets, etc. Common names are “cards” and “droplets” (key rings). Keys operating up to 10-15 cm are called Proximity (short-range), and keys operating up to 1 m are called Vicinity (long-range). Intercoms use exclusively Proximity keys, and this term has become almost synonymous with “contactless key”.

In the world of Proximity there is also no unity of formats:

EM-Marin

the most popular format today.

HID

elder among contactless keys.

MIFARE

promising format. This includes contactless smart cards.

This device is intended EXCLUSIVELY for copying contactless keys with a frequency of 125KHz.
No other keys can be copied.

Parcel contents:

Contents of delivery:

- RFID 125KHz EM4100 ID Card Copier;
- rewritable keychains 6 pcs;
- rewritable cards 6 pcs.;
- instructions (English-Chinese).
AAA batteries are not included.

Appearance of the device:

Internals of the device:

The device is in the on position:

(the red light is on, which means the device is turned on)

Key internals:

Instructions:

• Copy process:

1. Insert two AAA batteries.
2. Turn on the toggle switch located on the right side (the red indicator with the inscription POWER lights up and two short beeps are emitted).
3. We bring the card or keychain to the left side, at the level of the POWER inscription.
4. Press the “READ” button. In response, the duplicator will beep 2 times and the green LED with the inscription “PASS” will light up.
5. Remove the card or keychain from which the tag was read.
6. We bring the rewritable card or keychain to the copier. Press the “WRITE” button. The yellow LED with the inscription BUSY will light up for a while and again a double squeak will be heard. You can use the new key fob or card.

Video of the reading and writing process:

Bottom line.

Everything works great. If you need to make several copies of RFID 125KHz keys, you can safely buy them, especially since the set includes 6 key fobs and 6 cards, and the average price for one copy is 100 rubles, the benefits are obvious. If you run out of keychains or cards on the Internet, you can buy them for around 20 rubles.
Before purchasing this device, I recommend finding out the frequency and type of your key, otherwise you will be throwing money away.

If you liked the review or helped you in choosing a device, please give it a like, this is your best reward for my work.
Thank you all for your attention!

The product was provided for writing a review by the store. The review was published in accordance with clause 18 of the Site Rules.

I'm planning to buy +88 Add to favorites I liked the review +44 +83

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23.05.2012

A simple effective duplicator of intercom electronic keys with a working circuit is considered. The video shows the test and the finished assembly in action. There are many good schemes on the Internet for this function, but, firstly, they are complex, and secondly, not all of them work.

The creator of this video tutorial tried to assemble a key duplicator using an Arduino constructor, but it is not known why he did not succeed, despite the fact that there is a video on the Internet that demonstrates a working device on Arduino.

Factory duplicators are available for sale, but they are quite expensive, and for those who do not intend to always work on this device, there is no need to buy them. Since it’s not every day that amateurs need to duplicate keys for an intercom. It was decided to make a simple duplicator easily to expand our own horizons.

Many blanks were purchased on AliExpress, they are inexpensive. I found a simple circuit for making a duplicator, which can be assembled in almost 5 minutes. The blanks were purchased in this Chinese store, and in the same place there is a programmer necessary for the operation of the device.

discussion and diagram on the forum of this duplicate here. The base or heart of this copier is a microcontroller.

628, 648 or 88 will do. Of course, if you assemble the device easily, it won’t work. You need to write a program into this microcontroller. To do this, you will need a programmer that connects to the computer for firmware.

You can find instructions for using the programmer online. It costs 10-15 dollars. Any novice radio amateur will be able to use this microcontroller and repeat this duplicator circuit.

As you can see in the diagram and photo, there are 3 LEDs in the circuit - red, yellow and green.

The red LED lights up when there is power in the aggregate itself; yellow lights up while it is in key reading mode. And green lights up when the recording or duplication of the key was successful. The LEDs blink while the workpiece is disposable and non-rewritable.

All blanks purchased on AliExpress are rewritable.

The entire circuit is powered by 5 Volts. A 5 volt stabilizer was installed in this design, so that when a voltage is supplied from 5 to 9 volts, it always has only 5 volts at the output. The key duplicator itself is powered by a voltage of 5 Volts.

Let's turn it on and see how this device works. Turn on the power supply. All the LEDs lit up, in other words, the device booted.

We attach the copied key, the indicator shows reading. There is a button to duplicate this key. We apply a clean workpiece, the LED demonstrates that duplication has occurred. For the sake of experience, the key to the elevator was copied and tested.

The result is good, the duplicator, assembled with my own hands, works excellently.

Second part

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