KR940003262A - Ring Detection Method Using Microprocessor - Google Patents

Abstract

The present invention relates to a method for detecting a ring signal from a telephone network, and in particular, a system consisting of a device connected to a telephone network and a portable device for carrying or making a call while the user is carrying the ring signal transmitted from the telephone network. The present invention relates to a ring detection method that effectively distinguishes from a signal.

The ring detection method includes counting a period of a high logic input time of the waveform shaped signal in response to a waveform shaping circuit for shaping a signal input to a telephone line with a square wave and outputting the waveform from the waveform shaping circuit. Detect a ring signal using a microprocessor.

As described above, by detecting the ring signal by counting the input period of the signal, it is possible to accurately detect the ring signal.

Description

Ring Detection Method Using Microprocessor

Since this is an open matter, no full text was included.

2 is a circuit diagram of a radiotelephone according to the present invention;

4 is a ring interrupt flowchart according to the present invention;

5 is a timer control flowchart according to the present invention;

6 is a ring check control flow chart according to the present invention.

Claims (3)

An RF module 12 which transmits and receives an RF signal through an antenna, and a modem 14 connected to the RF module 12 to convert an analog signal input into a digital signal and convert the digital signal into an analog signal; In addition, the memory 16 stores the ID number of the fixed device (ID COED), the central processing unit (18) for controlling the peripheral device by the built-in program and performs a process, and the telephone network (PSTN) A ring having a call circuit 20 connected and transmitting and receiving a voice signal, and a waveform shaping unit 24 connected to the telephone network PSTN and waveform-shaping a signal of a predetermined level or more and outputting the signal to the CPU 18. A detection method comprising: driving a timer for checking a duration of a ring signal currently input while checking an RFCF in response to an interrupt by an input of a ring signal through the telephone network (PSTN), and calculating a frequency of the input signal TRC for A signal input detection process of storing the stored value in RC, and storing the value of the minimum frequency in the TRC, and reducing the maximum frequency value loaded in the TRC by operating a predetermined period, and the first level interval detection timer is timed out. A signal detection process for enabling the ring interrupt at the end), a ring detection state search process for searching whether a ring has already been detected, and a value stored in RC and a preset minimum value when it is determined that no ring has already been detected in the search process. A ring frequency first search process for searching a ring frequency compared to a frequency value, a call connection process for executing a call connection when the RC value is greater than a predetermined minimum frequency value as a result of the search in the ring frequency first search process; Ring note that searches for ring frequency by comparing the value stored in RC with the preset minimum frequency value when it is determined that the ring has already been detected in the search process The ring termination counter REC is counted when it is determined that the RC value is smaller than a preset minimum frequency value as a result of the second search process and the search of the ring frequency second search, and determines that the RC value is larger than the minimum frequency value. And a ring input state searching process for searching whether the REC is terminated when the REC is terminated, and stopping ringing when the REC is not finished in the ring input searching process, and stopping the call connection when the REC terminates. The signal input detection process of claim 1, wherein the signal input detection process comprises: an input signal state search process for searching whether a current input signal is a signal due to a falling edge in response to an interrupt by an input of a ring signal, and a falling edge during the signal state search process; The RC initializing process of resetting the rising edge detection flag and loading TRC value into RC when the signal is determined by the signal, setting the rising edge detection request bit, and setting the minimum frequency value to detect the ring. A TRC initialization process for loading a signal into the TRC, a process of setting a rising edge flag when setting the rising edge flag when determining that the signal is a rising edge signal, and disabling a ring interrupt. Method characterized in that consisting of. 3. The signal detection process according to claim 2, wherein the signal detection process includes: a timing search process for decrementing the value of TRC by a predetermined period and searching whether the "high" section detection timer expires when the rising edge detection flag is set; A ring signal search process for enabling a ring interrupt upon determining that the timer has expired in the timer search process and searching for whether the ring detection mode is “high”, and a ring detection port is “high” during the input search process for the ring signal. And resetting the rising edge detection flag at the same time as setting the high edge detection request bit at the same time, and immediately resetting the rising edge detection flag when the detection port is "low". ※ Note: The disclosure is based on the initial application.