CN102325017A - Communication speed adaption method for ball machine - Google Patents

Abstract

The invention relates to a communication speed adaption method for a ball machine. The method comprises the following steps: a 485 level signal is converted into a TTL (Transistor-Transistor Logic) level signal through a 485 chip; a pulse width capture unit generates capture response when the input TTL level signal is in a failing edge, a numerical value of a timer is stored into a designated register, and an interrupt signal is generated; a microprocessor answers the interrupt signal, and reads numerical numbers of the timer and marks the numbers to be t1 to tn in sequence; the time interval among the failing edges is calculated, and a minimum value is found out from the time intervals; Tmin is different regarding different communication speeds, so that the Baud rate of a received communication signal can be determined by the Tmin; and the microprocessor sets the internal UART (Universal Asynchronous Receiver Transmitter) Baud rate, so that the internal UART Baud rate is in accordance with the Baud rate of the received control signal, when a system changes the Baud rate of the communication circuit, the ball machines can automatically detect the communication speed of the received control signal and regulate the own communication speed to be in accordance with that of the system. Therefore, the hardware of the site ball machine is avoided setting, and more flexibility is brought to site construction debugging, and labor cost is effectively reduced.

Description

The communication speed adaptive approach that is used for the ball machine

Technical field

The present invention relates to the intelligent video monitoring technical field, particularly a kind of communication speed adaptive approach that is used for the ball machine,

Be applied to safety monitoring, infrared ball monopod video camera and intelligent sphere monopod video camera.

Background technology

In safety defense monitoring system construction or escalation process, run into the situation of changing 485 communication line baud rates through regular meeting, general ball machine need be adjusted communication baud rate through the dial-up that equipment itself is set.This operation is relatively easy for placing indoor master control or memory device, and for being installed to the on-the-spot ball machine of monitoring, because the particularity of its operational environment, difficulty is compared in this set operation sometimes.Therefore, show important for the communication speed adaptive approach application of ball machine is just outstanding.

Summary of the invention

The object of the invention is exactly the deficiency that exists to prior art, to the problems referred to above, considers that monitoring is on-the-spot through the existing difficulty of hardware setting change ball machine baud rate; A kind of communication baud rate adaptive technique scheme is provided; Make the ball machine increase the communication baud rate adaptation function, promptly the ball machine can detect the baud rate of 485 communication lines automatically, when the communication system baud rate changes; The ball chance is adjusted self communication speed automatically, keeps consistent with whole system.

The present invention realizes through such technical scheme: be used for the communication speed adaptive approach of ball machine, it is characterized in that, said method comprises the steps:

A, microprocessor and 485 chips are constituted hardware circuit be connected to the ball machine circuit; 485 level signals that transmit ball machine circuit control end through 485 chips convert the discernible Transistor-Transistor Logic level signal of microprocessor into, and the Transistor-Transistor Logic level signal is transferred to the UART module and the pulsewidth capture unit of microprocessor internal simultaneously;

B, when the Transistor-Transistor Logic level signal of input when being in trailing edge; The pulsewidth capture unit produces catches response, and the timer count value was stored and specified in the register this moment, and produced interrupt signal; The microprocessor responds interrupt signal reads the timer count value and is labeled as t successively ₁To t _n

C, calculate the time interval between each trailing edge: T ₁=t ₂-t ₁, T ₂=t ₃-t ₂... T _N-1=t _n-t _N-1; And therefrom find out minimum value: T _Min=min{ T ₁, T ₂T _N-1; For different communication speed T _MinDifference therefore can be according to the T that obtains _MinThe baud rate of the communication signal of confirming to receive;

D, microprocessor are provided with the baud rate of inner UART module, and the baud rate of the communication signal of the ball machine circuit that makes it and receive is consistent.

Beneficial effect: safety defense monitoring system is when changing the communication line baud rate, and the communication speed that the ball machine can detect the communication speed of the control signal that receives automatically and adjust self makes it consistent with whole system; Thereby avoided on-the-spot ball machine hardware is provided with, brought very big flexibility, and effectively reduced because the paying of the human cost that change communication line baud rate is brought to site operation debugging.

Description of drawings

Fig. 1, be used for the communication speed adaptive circuit structure chart of ball machine;

Fig. 2, Transistor-Transistor Logic level signal timing diagram.

Embodiment

Understand the present invention for clearer, describe the present invention in detail in conjunction with accompanying drawing and embodiment:

As shown in Figure 1: that microprocessor and 485 chips formation hardware circuit are connected to ball machine main circuit; As shown in Figure 2: Transistor-Transistor Logic level signal sequence, the time interval T between each trailing edge ₁=t ₂-t ₁, T ₂=t ₃-t ₂... T _N-1=t _n-t _N-1; Minimum value T _Min=min{ T ₁, T ₂T _N-1; For different communication speed T _MinDifference therefore can be according to the T that obtains _MinThe baud rate of the communication signal of confirming to receive.

According to above-mentioned explanation, can realize scheme of the present invention in conjunction with art technology.

Claims (1)

1. be used for the communication speed adaptive approach of ball machine, it is characterized in that, said method comprises the steps:

A, microprocessor and 485 chips are constituted hardware circuit be connected to the ball machine circuit; 485 level signals that transmit ball machine circuit control end through 485 chips convert the discernible Transistor-Transistor Logic level signal of microprocessor into, and the Transistor-Transistor Logic level signal is transferred to the UART module and the pulsewidth capture unit of microprocessor internal simultaneously;

B, when the Transistor-Transistor Logic level signal of input when being in trailing edge; The pulsewidth capture unit produces catches response, and the timer count value was stored and specified in the register this moment, and produced interrupt signal; The microprocessor responds interrupt signal reads the timer count value and is labeled as t successively ₁To t _n

C, calculate the time interval between each trailing edge: T ₁=t ₂-t ₁, T ₂=t ₃-t ₂... T _N-1=t _n-t _N-1; And therefrom find out minimum value: T _Min=min{ T ₁, T ₂T _N-1; For different communication speed T _MinDifference therefore can be according to the T that obtains _MinThe baud rate of the communication signal of confirming to receive;

D, microprocessor are provided with the baud rate of inner UART module, and the baud rate of the communication signal of the ball machine circuit that makes it and receive is consistent.

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