CN206790498U - A kind of CDR terminal devices using IIC communications protocol - Google Patents

Abstract

The utility model provides a kind of CDR terminal devices using IIC communications protocol, including for reception signal and the CDR data output circuits that are tuned, demodulate, decode, external equipment；Wherein described CDR data output circuits connect the external equipment by IIC protocols；Wherein described CDR data output circuits send an initial data-signal, then send 7 bit address data of the external equipment to be accessed, and wait the answer signal of outside；Wherein described CDR data output circuits perform following operate：If CDR data output circuits read in data, then SDA buses are set to input pattern, and maintain the working method of SDA buses constant in the data transmission, and often read in a byte and detect answer signal successively；If CDR data output circuit output datas, then be arranged to the way of output by SDA buses, it is necessary to which it is input mode to change SDA line after a byte has been sent, and the transmission of the byte is completed after the answer signal of outside is received；After all data transfers, CDR data output circuits send a stop signal by SDA buses, to terminate this data transfer.

Description

A kind of CDR terminal devices using IIC communications protocol

Technical field

It the utility model is related to electronic technology field, more particularly to a kind of CDR terminal devices using IIC communications protocol.

Background technology

Chinese Digital audio broadcasting CDR (China Digital Radio, CDR) be after AM and FM audio broadcasting technologies it After grow up ground third generation broadcast technology, be China's broadcasting digitalization process an important component, be broadcast Digitized developing direction, it is the digital broadcast audio standard that China has independent intellectual property right.

CDR allows to transmit the digital stereophonic program of more sets or all the way surround sound program in an analog fm channel, and Keep preferable subjective sound quality, while can match channels layering feature, using the teaching of the invention it is possible to provide stereo and two kinds of layerings of surround sound Coding mode, so as to take into account the service range of digital frequency modulation broadcast and service quality.CDR transmission plans are directed to different operations Scene, three kinds of transmission modes are set, first, being covered for the SFN of large area, an emitter can cover tens kilometers Scope, also high-speed mobile receive, as we country high ferro, per hour more than 300 kilometers of speed received.It is also high Data rate transmission, higher data volume can be transmitted on frequency.Because CDR is a kind of very new technology, therefore lack now Efficient and feature-rich DCR receiving terminal apparatus.

Utility model content

The problem of for lacking efficient and feature-rich DCR receiving terminal apparatus present in prior art, this practicality New embodiment proposes a kind of design more rational CDR terminal devices using IIC communications protocol.

To achieve these goals, the utility model embodiment proposes a kind of is set using the CDR terminals of IIC communications protocol It is standby, including for reception signal and the CDR data output circuits that are tuned, demodulate, decode, external equipment；Wherein described CDR Data output circuit connects the external equipment by IIC protocols；

Wherein described CDR data output circuits send an initial data-signal, then send the external equipment to be accessed 7 bit address data, and wait outside answer signal；Wherein described CDR data output circuits perform following operate：

If CDR data output circuits read in data, then SDA buses are set to input pattern, and in the data transmission Maintain the working method of SDA buses constant, and often read in a byte and detect answer signal successively；

If CDR data output circuit output datas, then be arranged to the way of output by SDA buses, when having sent one , it is necessary to which it is input mode to change SDA line after byte, and the transmission of the byte is completed after the answer signal of outside is received； After all data transfers, CDR data output circuits send a stop signal by SDA buses, to terminate the number According to transmission.

Wherein, the external equipment is display circuit so that CDR data output circuits data to be shown are sent to it is aobvious Show that circuit is shown；Wherein described data to be shown include following at least one：Display program title, signal intensity, Programme information push, song title, date-time information；

Wherein described display circuit includes ST7032 chips, the SDA that the ST7032 chips pass through IIC protocol interfaces Bus connects the CDR data output circuits with SCL buses, by the order received in SDA buses and SCL buses and data It is converted into the character that can show and is shown by display screen.

Wherein, display circuit also includes 1602 alphanumeric displays provided with IIC interfaces, and 1602 alphanumeric display passes through IIC interfaces connect ST7032 chips.

Wherein, the CDR data output circuits include：Antenna, the tune for being tuned to the signal that antenna receives Humorous device, for the signal after tuning is demodulated demodulation chip, for the data obtained after demodulation to be decoded to obtain Obtain the main control chip of audio/video/picture；Wherein described antenna connects demodulation chip, and the demodulation chip by tuner By being communicated between following at least one agreement and main control chip：SPI protocol, I2C agreements, TS agreements；And the master Control chip and connect the display circuit.

Above-mentioned technical proposal of the present utility model has the beneficial effect that：One kind is proposed in such scheme using IIC to lead to Interrogate the CDR terminal devices of agreement, can connect multiple external equipments by IIC protocol interfaces, and by the way of 7 bit address come Distinguish external equipment.The function and availability of whole CDR terminal devices can thus be improved.The utility model includes one kind The IIC means of communication of CDR terminal devices, the major functions of the CDR terminal devices include CDR frequencies are played, FM is played, MP3 and The systems such as the broadcasting of WMA audios, date and time and alarm clock setting are set.The CDR terminals are using IIC interface modes by master control core Piece is connected to peripheral hardware --- alphanumeric display, to display program title, signal intensity, programme information push, song title, day The information such as time phase.The utility model describes a kind of mode that chip on CDR terminal devices is connected with peripheral hardware --- IIC interfaces Connection, and illustrate the structure of the connected mode and operation principle using character type dot matrix display screen.The control core of CDR terminals 1602 alphanumeric displays of IIC interfaces are connected to by IIC interfaces, the ST7032 cores of Xi Chuan companies are integrated with the display screen Piece, the character that the order and data that are received on SDA and SCL lines are converted into showing by the chip, so as to be shown to 1602 On screen.

Brief description of the drawings

Fig. 1 is the schematic diagram of IIC universal serial bus；

Fig. 2 is the schematic diagram that iic bus transmitting procedure starts and stopped；

Fig. 3 is that IIC data/address bus transmits sequential；

Fig. 4 is legal IIC data transmission formats；

Fig. 5 is the form schematic diagram of IIC communication protocols.

Embodiment

To make the technical problems to be solved in the utility model, technical scheme and advantage clearer, below in conjunction with accompanying drawing And specific embodiment is described in detail.

IIC (Inter-Integrated Circuit, IC bus) is 80 by Philips Semiconductor Co., Ltd. Designed at the beginning of age, be primarily used to connect integrated circuit (ICS).IIC is a kind of multidirectional controlling bus, that is to say, that more Individual chip may be coupled under same bus structure, while each chip can serve as the voltage input of real-time Data Transmission.This Kind mode simplifies signal transmission bus interface.Iic bus possesses the function such as bus arbitration function and the synchronization of high low-speed device The more host buses of high-performance, equipment directly is connected with wire, without chip selection signal during communication.With large scale integrated circuit technology Development, the peripheral circuit such as ROM, RAM, I/O port, A/D, D/A necessary to CPU and system that works independently is used IIC Interface integrations in a monolithic and manufactured single-chip microcomputer or microcontroller are more and more convenient.

The utility model provides a kind of CDR terminal devices using IIC communications protocol, the CDR terminal devices it is main Function includes：The systems such as the broadcasting of CDR frequencies, FM broadcastings, the broadcasting of MP3 and WMA audios, date and time and alarm clock setting are set Put.The CDR terminals are connected to peripheral hardware using IIC interface modes by main control chip --- alphanumeric display, to display program name The information such as title, signal intensity, programme information push, song title, date-time.CDR terminals in the utility model embodiment Connected in equipment between chip and peripheral hardware using IIC interfaces, and illustrate the connected mode using character type dot matrix display screen Structure and operation principle.The control core of CDR terminals is connected to 1602 alphanumeric displays of IIC interfaces by IIC interfaces, and this is aobvious The ST7032 chips of Xi Chuan companies are integrated with display screen, the order and data that are received on SDA and SCL lines are converted into by the chip The character that can be shown, so as to be shown on 1602 screens.

IIC structure function explanations：

As shown in Figure 1, IIC universal serial bus typically has two signal wires, and one is two-way data wire SDA, Ling Yigen It is clock line SCL.All serial data SDA being connected in iic bus equipment are connected on the SDA of bus, the clock of each equipment Line SCL is connected on the SCL of bus.In order to avoid the confusion of bus signals, it is desirable to which each equipment must when being connected to the output end of bus Must be open-drain (OD) output or open collector (OC) output.Serial data line SDA interface circuits in equipment should be Two-way, output circuit is used to in bus send data, and input circuit is used to receive the data in bus.And serial time clock line Also should be it is two-way, as controlling bus data transmission main frame, on the one hand will by SCL output circuit tranmitting data register signals, On the other hand the SCL level in bus is also detected, to decide when to send next clock pulses level；As receiving The slave of Host Command, the signal on SDA is sent or received by the SCL signal in bus, low electricity can also be sent to SCL lines Ordinary mail number is to extend the bus clock signal cycle.During bus free, because each equipment is all open-drain output, pull-up resistor Rp makes SDA High level is all kept with SCL lines.The low level of any appliance output will all make corresponding bus signal line step-down, that is to say, that： The SDA of each equipment is "AND" relation, and SCL is also "AND" relation.

As shown in Figure 2, in iic bus transmitting procedure, two kinds of specific situations are defined as beginning and stop condition： When SCL keeps " height ", it is beginning condition that SDA is changed into " low " from " height "；When SCL holdings " height " and SDA is changed into " height " from " low " When be stop condition.Start and stop condition produces by master controller.It can be reliably detected out using hardware interface Beginning and stop condition, SDA must be sampled at least twice with per clock cycle without the microcomputer of this interface, to detect this change Change.

As shown in Figure 3 transmits sequential for IIC data/address bus.Data on SDA line must be steady during clock " height " Fixed, only when the clock signal on SCL lines is low, " height " or " low " state on data wire can just change.It is output to Each byte on SDA line must be 8, and the byte transmitted every time is unrestricted, but each byte must have a response ACK.If a receiving device when the complete bytes of another data can not be received before completing other functions (a such as internal interrupt), It can keep clock line SCL to be low, to promote transmitter to enter wait state；When receiver is ready to receive the other of data Byte and after discharging clock SCL, data transfer continues.

It is necessary that data transmission, which has response,.Clock pulses corresponding with response is produced by master controller, and transmitter exists SDA line must be pulled down during response.When the controlled device of addressing can not reply, data, which remain height and produce main controller, stops Only condition and terminate transmission.During transmission, in the case where using master control receiver, master control receiver must send out one End of data signal gives controlled transmitter, so that controlled transmitter release data wire, to allow main controller to produce stop condition. Legal data transmission format is as follows：

First byte of the iic bus after beginning condition determines which controlled device will be selected by main controller, except that " general Access " address, it can be addressed in all periods.When main controller exports an address, each device in system will all start Preceding 7 bit address and the address of oneself after condition are compared.If identical, the device thinks that oneself is addressed by main controller, And it is used as passive controlled receiver or controlled transmitter then to depend on R/W positions.

In 1602 display screen display content of the IIC interfaces using integrated ST7032 chips, first by CDR terminal device controls Core processed sends an initial data-signal, then sends out the 7 bit address data that access device, and waits answering for controlled device Answer signal.After answer signal is received, operated accordingly according to visiting demand.If reading in data, then data wire can Input mode is set to always, and centre need not change the working method of SDA line, and response all should be detected successively by often reading in a byte Signal；If output data, then SDA is arranged to the way of output first, it is necessary to change SDA after a byte has been sent Line is input mode, and the answer signal for now reading in controlled device just completes the transmission of a byte.When all data transfers After, a stop signal should be sent to SDA, to terminate this data transfer.During using IIC interface screens, communication protocol Form it is as shown in Figure 5.Wherein Co=0 represents last control of transmission Byte；Only a data Byte is allowed to flow therewith.Should Data Byte streams only can be just suspended under halted state；Wherein Co=1 represented unless receive halted state, otherwise data Byte is followed by another control Byte.

Described above is preferred embodiment of the present utility model, it is noted that for the ordinary skill of the art For personnel, on the premise of principle described in the utility model is not departed from, some improvements and modifications can also be made, these improvement The scope of protection of the utility model is also should be regarded as with retouching.

Claims (4)

1. A kind of 1. CDR terminal devices using IIC communications protocol, it is characterised in that including for reception signal and be tuned, Demodulation, the CDR data output circuits of decoding, external equipment；Wherein described CDR data output circuits are connect by IIC protocol communications Mouth connects the external equipment；

   Wherein described CDR data output circuits send an initial data-signal, then send 7 of the external equipment to be accessed Address date, and wait the answer signal of outside.
2. 2. the CDR terminal devices according to claim 1 using IIC communications protocol, it is characterised in that the external equipment For display circuit, shown so that data to be shown are sent to display circuit by CDR data output circuits；It is wherein described to treat The data of display include following at least one：Display program title, signal intensity, programme information push, song title, date Temporal information；

   Wherein described display circuit includes ST7032 chips, the SDA buses that the ST7032 chips pass through IIC protocol interfaces The CDR data output circuits are connected with SCL buses, by the order received in SDA buses and SCL buses and data conversion Shown into the character that can be shown and by display screen.
3. 3. the CDR terminal devices according to claim 2 using IIC communications protocol, it is characterised in that display circuit also wraps 1602 alphanumeric displays provided with IIC interfaces are included, 1602 alphanumeric display connects ST7032 chips by IIC interfaces.
4. 4. the CDR terminal devices according to claim 2 using IIC communications protocol, it is characterised in that the CDR data Output circuit includes：Antenna, for the signal that antenna receives is tuned tuner, for entering to the signal after tuning The demodulation chip of row demodulation, for the data obtained after demodulation to be decoded to obtain the master control core of audio/video/picture Piece；Wherein described antenna by tuner connect demodulation chip, and the demodulation chip by following at least one agreement with Communicated between main control chip：SPI protocol, I2C agreements, TS agreements；And the main control chip connects the display circuit.