Epson V7 User Manual

3-20

5. Universal Serial Communications

Universal Serial
Communications

Universal Serial Communications

• A general purpose computer or an ASCII unit of the PLC (master station) controls the

V7 series (slave station) using dedicated commands.

• The V7 series internal user memory addresses ($u) must be used for memory

allocation for switch, lamp or data display parts. When the master station specifies a
screen number, data is written to the internal memory address ($u) allocated for the
screen. If the screen is switched internally, the new screen number is read and is
written to the internal memory address ($u) allocated for the screen.

• For 1 : 1 connection, the V7 series can send an interrupt to the master station through

switch activation, write command from the keypad, and screen change.

• Use CN1 of the V7 series for connection with a general-purpose computer. Either

signal level RS-232C or RS-422 (RS-485) can be selected.

• In addition to 1 : 1 connection, 1 : n connection is available between the

general-purpose computer and the V7 series via RS-422. (A maximum of 32 V7 series
can be connected.) For 1 : n connection, interrupts cannot be used.

• For more information, refer to the V series Universal Serial Connection Manual.

RESET

disc

SYSTEM

POWER

CN1

RS-232C or RS-422 (RS-485)

V7 series

Write

General-purpose computer

Dedicated commands

Interrupt

Read

CN1

SYSTEM

POWER

SYSTEM

POWER

SYSTEM

POWER

SYSTEM

POWER

CN1

SYSTEM

POWER

SYSTEM

POWER

SYSTEM

POWER

SYSTEM

POWER

RS-42 (RS-485) connection

V7 series No. 1

General-purpose
computer

V7 series No. 2

V7 series No. 3

V7 series No. “n” (n = 1 to 32)