Mitsubishi Q2ACPU, User Manual

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2.
2 - 1
OVERVIEW
2 OVERVIEW
2.1 Features
QnACPU has the following features.
(1) Large memory capacity
(a) Q4ACPU has a program capacity of 124k steps, which means that 124k steps
can be used for a single program (Q2ACPU: 28k steps, Q2ACPU-S1: 60k steps,
Q3ACPU: 92k steps).
(b) The device memory capacity is 32k words and the user can change the number
of points as required.
For example, the default number of points for internal relays (M) is 8k points, but
this can be expanded up to 32k points.
(c) Two memory cards of a maximum of 2M bytes can be installed.
Memory cards are used to store programs, comments, statements, and file
registers.
(Programs can be stored in the CPU module itself, so a memory card is not
essential to run a CPU module.)
(2) High-speed processing
(a) Higher operation processing speeds have been achieved for basic instructions
and application instructions.
(b) The access time for expansion data memory (file registers: R) has been
conformed with the internal devices of the QnACPU (data registers: D, and link
registers: W).
(c) Reading/writing of the buffer memories of special function modules dedicated to
QnA (serial communication modules) have been realised processing speed-up
by six times compared to AnUCPU.
(The processing speed of the existing special function modules for ACPU use is
about the same as that when using AnUCPU.)
(d) A high-speed access base unit (A38HB/A38HBEU) is available to speed up the
processing time for accessing special function modules such as network
modules and serial communication modules that handle large quantities of data.
Simply by mounting the special function module on the high-speed access base
unit, the access processing speed is increased when the QnACPU accesses the
special function module.
A4UCPU Q4ACPU
Basic instruction 0.15 s 0.075 s
Application instruction 0.90 s
0.225 s