CPU performance and scan timing
The Q04UDHCPU: Constant scan interval settable from 0.5 to 2000ms in 0.5ms steps, giving deterministic control over program execution timing. Control method is stored program repeat operation, the standard for reliable machine sequencing.
Memory and expansion
Program memory is 40K steps (160K bytes), with standard RAM of 2048 points for latch and device memory. Memory card interface supports SRAM, Flash, and ATA cards — Flash up to 4M bytes, ATA up to 32M bytes. Flash card slots accept up to four cards for recipe storage or program backup.
Comparison with iQ-R series
The R08ENCPU from the iQ-R series doubles program capacity to 80K steps and includes a built-in CC-Link IE port, but requires a different backplane and draws 1.49A at 5V versus 0.39A. Footprint is larger (56 x 106 x 110 mm vs 98 x 27.4 x 89.3 mm).