Mitsubishi Electric AJ71C24-S6 User Manual page 254

10. COMMUNICATIONS IN THE BIDIRECTIONAL MODE
MELSEC-A
(2) Buffer memory used in the bidirectional mode
(a) Special applications area (100H to IFFH)
-
Address Name
Wordlbyte designation area
for bidirectional mode
Bidirectional mode send buffer
memory area head address
designation area
Bidirectional mode send buffer
memory length designation
area
Bidirectional mode receive
buffer memory area head
address designation area
Bidirectional mode receive
buffer memory length designa-
tion area
Description
The unit (wordlbyte) of data length of a message transmittted between
a computer and a PC CPU is designated with a TO instruction in a
sequence program.
This sets the unit of data to be stored in the send data length storage
area (default address OH) and the received data length storage area
(default address 80H).
0: Word (default)
1: Byte
The head address of the area used for bidirectional mode send buffer
memory area (send data length storage area and send data strage
area) is designated with a T O instruction in a sequence program.
The area of the designated address is set as the send data length
storage area. (0 to FEH or 20H to 7FEH : Bidirectional send buffer
memory head address. (default : OH)
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The lenoth of the area used for bidirectional mode send is desianated
-
with a TO instruction in a sequence program.
(default: 80H).
When O H to FFH area is used.
2H to 100H: Bidirectional send buffer memory
When 120H to 7FFH
area
is used.
2H to 6EOH: Bidirectional send buffer memory length
The head address of the area used for bidirectional mode receive
buffer area (receive data length storage area and receive data storage
areal is designated with a TO instruction in a sequence Drogram.
.
The area of &e designated address is set as the'receive daja length
storage area.
O H to FEH 20H to 7FEH: Bidirectional mode receive buffer memory
head address. (default: 80H)
The length of the area used for bidirectional mode data receive is
designated with a TO instruction in a sequence program (default:
80H).
When O H to FFH area is used.
2H to 100H: Bidirectional receive buffer memory length
When 120H to 7FFH area is used.
2H to 6EOH: Bidirectional receive buffer memory length
(continued on page
10-6)