S7-200 PLC type of interrupt sources

S7-200 sets the interrupt function for real-time control, high-speed processing, communications and control of complex and special tasks such as network. Disruption is to terminate the currently running program, to carry out immediate interrupt service program has been developed in response to signals, is complete and then return terminated the program and continue to run.
Interrupt sources of interrupt request is issued, also known as interrupt event. For ease of identification, the system gives each interrupt source is assigned a number, known as an interrupt event. S7-200 series programmable controllers up to 34 interrupt sources, divided into three categories: loss of communication, time base and input/output interrupt interrupts.

(1) communications
In the free port mode, users can programmatically set the baud rate, parity, and the communication protocol and other parameters. User programmatic control of communication port event for loss of communication.

(2) the I/O interrupts
I/O interrupt include external input rising/falling edge interrupt, high speed and high speed pulse output interruption of their counter. S7-200 input (I0.0, I0.1, I0.2, or I0.3) rising/falling edge interrupts. These entry points are used to capture events that occur must be dealt with immediately. High-speed digital high speed counter in the counter running events that occur when the real-time response, including the current interrupts that occur when the value is equal to the default value, change counting direction when interrupted or counter external reset interrupt. Pulse output interrupt is scheduled to be completed number of pulse output and disruption.

(3) the time base break
Includes timer interrupt and timer T32/T96 interruption of their timing. A periodic timer interrupt is used to support activities. From 1 MS to 255 Ms cycle time, the time base is 1 Ms. Using the timer interrupt 0, must write a cycle time SMB34; using the timer interrupt 1, must be written in SMB35 cycle time. On the timer interrupt event will break the connection, if the timer interrupt allowed, you set start time, whenever the time value is reached, the interrupt programs. Timer interrupt can be used for analog input is sampled or regular PID loop. T32/T96 finger allows to set the time interval of the timer interrupts. Such disruption can only use timebase as 1ms timer T32/T96 component. When interrupts are enabled, current value equal to the preset value, the normal 1 millisecond timer S7-200 perform in the process of updating, the interrupt program execution.