The Mitsubishi CPU unit AD75TU features 1024 I/O points, 1024 I/O data device points, a program capacity of 14k steps, and a basic command processing speed (LD) of 0.20μs. PLCs can be either integrated (compact, all-in-one, typical for small PLCs) or modular (separate components, typical for medium/large PLCs, easier to maintain). During each scan cycle, inputs are sampled and outputs are refreshed in a concentrated manner. If an input changes during program execution, it is not read until the next scan. A scan cycle includes input sampling, program execution, and output refresh. The contents of the image register change as the program runs. Scan cycle length depends on CPU speed, instruction execution time, and the number of instructions. Due to concentrated I/O processing, there is a delay in I/O response. User program storage capacity is measured in words or K words (1 word = 16 bits, 1K words = 1024 words). Basic logic instructions typically take 1 word, timer/counter/shift instructions take 2 words, and data operation instructions take 2 to 4 words.