Q1: What is a digital counter?
Counting is one of the simplest and most basic operations. In digital logic and computing, a counter is the logic circuit that implements this operation. In digital systems, a counter mainly counts the number of pulses for measurement, counting, control, and other functions. It also has a frequency division function. A digital counter consists of a basic counting unit and some control gates. The counting unit consists of a series of various flip-flops with the function of storing information. These flip-flops include RS flip-flops, T flip-flops, D flip-flops and JK flip-flops. Counters are widely used in digital systems. For example, in the controller of an electronic computer, the next instruction is taken out sequentially by counting the instruction address. The operation unit records the number of additions and subtractions when multiplication and division operations are performed. A counter can be used to indicate the operating status of a product. In general, it is mainly used to indicate how many copies of the product have been folded and sorted. Its main indicator lies in the number of bits of the counter, commonly 3 and 4 bits. Obviously, a 3-digit counter can display up to 999 and a 4-digit counter can display up to 9999.
Q2: How to choose a digital counter?
- The choice of the built-in crystal oscillator.
- The resolution of the digital counter.
- Large screen touch design.
- The counter has more measurement functions.
- Internal crystal oscillator calibration function.
- The communication interface of the counter should be as many as possible.
- Wide measuring range
Q3: Types of counters
- According to whether the flip-flops in the counter are flipped at the same time, the counter can be divided into two types: synchronous counter and asynchronous counter.
- According to the increase and decrease of numbers in the counting process, the counters can be divided into addition counters, subtraction counters, and reversible counters. It is an up counter that keeps increasing with the clock signal, and a down counter that keeps decreasing. A counter that can be incremented or decremented is called a reversible counter.
The most commonly used is the first one because it allows people to know at a glance what triggering method this counter is so that designers can design circuits.
Tips: Digital counter application in positioning control
The paper cutter is one of the most commonly used pieces of equipment in the printing and packaging industry. The most basic action of a paper cutter is to send the material to be cut to the designated location and then cut it. Using the high-speed counting function of the counter in the PLC positioning system and combining the multi-speed function of VFD can achieve positioning control, and using HMI can perform cutting parameter setting and some manual actions. This control system can well solve the phenomenon the positioning inaccuracy, the cutting action is disordered, and normal production cannot be performed, which are caused by the aging of the SCM system after use for a period of time.