Table of Contents
Advertisement
9. COMMUNICATIONS IN THE NO-PROTOCOL MODE
MELSEC-A
9.6
Sending Data in the No-Protocol Mode (AJ71C24
+
External Device)
In this section, "sending" means outputting data which is in the no-protocol
mode AJ71C24 send area to an external device receive area. This is in
response to turning the PC GPU send request signal (Y(n+l)O) ON.
(1) Send area and writing send data
The send data length and send data are written to the send area.
(a) The length of send data to be written (or having been written) to the
send data storage area is written to the no-protocol send data
length storage area in either words or bytes.
(b) The data to be transmitted is written to the send data storage area.
When the send request signal (Y(n+l)O) is turned ON after (a) and
(b) have been executed, the AJ71C24 transmits the set length of
set data from the send data storage area in the order of address
number.
By default, buffer memory area O H to 7FH is allocated to the
AJ71C24 send area.
It is however possible to change the send area allocation. (See
Section 7.4.4.)
I
The unit wordlbyte of send data
Address
- - - -
length depends on the setting
(default)
Buffer memory
(address
103H).
O H
Send data length
IH
Use the TO instruction to set the
to
length of data to be transmitted.
7FH
1
Data to be transmitted is stored
I
sequentially from the lowest ad-
dress.
Advertisement
Table of Contents
