ENCODER IN MITSUBISHI FX3U AND HIGH SPEED COUNTER

1. Types of high-speed counters
The main unit has built-in 32-bit high-speed bi-directional counters (1-phase 1-count, 1-phase 2-count and 2-phase 2-count). These high-speed counters are classified into hardware type or software type according to the counting method. Some high-speed counters are capable of using an external reset input terminal and an external start input terminal (for counting start).
2. Classification of high-speed counters according to counting method
→ Hardware counters: These types of counters execute counting by hardware, but may be switched to software counters depending on the operating condition.
→ For the condition handled as software counters, refer to Subsection 4.7.9.
→ Software counters: These types of counters execute counting as CPU interrupt processing.
It is necessary to use each software counter within both limitations of maximum response
frequency and total frequency.
Cautions on counterpart equipment connected to high-speed counter inputs
General-purpose inputs X000 to X007 are used for high-speed counter inputs. An encoder*1 adopting the output method shown in the table below can be connected depending on the connected terminal.
Encoders adopting the voltage output method and absolute encoders cannot be connected to high-speed counterinputs.