In our magazine have described a phone with auto detection the number of the caller (caller ID) and phone consoles developed by the company TeleSystems. Today we will talk about adding features caller ID in the telephone Panasonic KX-T2365".
It is known that most phones with caller ID is made on the basis of cheap of Asian production. But first, these phones are not very well to put in the office, and secondly, their mechanical elements do not differ high reliability. To have such a device at home, where it is not subjected to intensive use, still acceptable, but if you work with your phone the whole day, then after a while it start to function keys unclear. From this we can conclude that the caller ID, which appearance is not spoil the interior and a long daily work which will not cause headache, should be based on the IP phones companies that high quality.
One of the most common modern telephones in Russia is "Panasonic KX-T". A well thought out design, reliability, availability LCD display make it attractive to buyers.
Therefore it is quite natural desire to add to this device functions The caller ID. This idea was implemented by the firm "TeleSystems". The phone is embedded a small fee is performing the function of caller ID. Thus all basic functions of the phone are saved.
Additional fee not only allows to determine the number of the caller, but and implements the automatic dozarivaniya to busy subscriber, provides storage and display up to 99 numbers callers with callers information about the time and day of week the call was made. With the help of this Board fixed the number that is dialed with Panasonic'or a parallel phone apparatuses. Both types of memory allow for automatic dialing stored rooms. In addition, the possibility of a ban of long-distance and set international phone numbers and function telephone protection from pirate connections.
The scheme of the extra cost of the phone shown in the picture. The basis of the device - microprocessor controller PIC16C62 from Microchip Technology, Inc. (DD1 chip). For data storage nonvolatile used FLASH memory part no 24lc16b with the interface κ 2C and the organization CH (chip DD2). The additional connection Board main Board Panasonic phone is performed using a 17 segment bonding wire. Board size - 12,h,5 mm.
The signal from the telephone line enters the charge on the chain IN. Resistors R5 and R6 assembled sensor of the call that is triggered when the line voltage 110V (alarm BELL). The sensor picking up the handset parallel phone serves as a divider the voltage on the resistors R3 and R4 (signal ULN). Activate this switch the voltage of 27 V. the Signal you pick up the handset on your phone comes with a basic Board (TUB). Information for determining the number of the subscriber is supplied from the output the comparator on the main Board (SIG). Optocoupler U1 provides circuit ringing of the telephone. Signals to the telephone line (sending request, imitation rings) go through the chain of LSND. Lock sound at the time of determining the number by feeding the signal to the main Board of the phone (SMUTE).
Resistors R7, R8 and capacitor C2 determine the frequency of the internal clock generator controller. It depends on the level of the signal at the output RC0/T1C chip DD1 (signal F). At high frequency must be 5 MHz ±10%, and when this pin is set to Vysocina-dansee status - 0.3 MHz. For reduce the power consumption of the controller most of my time is in mode with a low clock frequency. The high clock frequency is used when the analysis of signals from the line. Time synchronization controller is a signal with a frequency of 32 768 Hz coming from the main Board of the phone (chain 32K). The signal RES resets the controller.
To manage your phone extra charge monitors keystrokes. For this examines the state of the first output keyboard scan (SCAN) and signals read keyboard status (KDO - KD3). For keys that served by other outputs of the scan, the status is read from proper delay from receipt of a pulse on the SCAN chain by the same circuits KDO - KD3. On a similar principle and built to emulate button presses, necessary to manage the phone and to perform intended functions. For this controller puts in the appropriate time necessary level on circuits KDO - KD3.
Authors: E. Kabakov, I. Kite, Zelenograd