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MELSEC-Q
3   SPECIFICATIONS 
 
(b)    In the QD51 (-R24), reading of data from, or writing of data to buffer 
memory is done using the GETMEM/PUTMEM command in the BASIC 
program. 
 
Programmable 
controller 
CPU
TO 
(Writing of data)
FROM 
(Reading of data)
Buffer 
Memory
BASIC 
program
QD51(-R24)
GETMEM 
(Reading of data)
PUTMEM 
(Writing of data)
 
 
Program example 
The following shows a program where data from A%(0) to A%(9) 
(equivalent to 20 bytes) are written into the buffer memory area 
addressed 0
H
 to 13
H
 using the PUTMEM command. 
 
100 PUTMEM TO 0, 0 FROM A%(), 0, 20 
 
Buffer Memory
0
H
1
H
2
H
13H
11H
10
H
3
H
12
H
0H
1
H
9
H
8
H
PUTMEM
 (Writing of data)
BASIC
Program
(1-byte units)
QD51(-R24)
to
to
 
 
(2)   Buffer Memory Capacity 
The capacity of the QD51 (-R24)'s buffer memory is 3 k words (6 k bytes). 
 
(3)   Buffer Memory Configuration 
One address of the buffer memory is composed by 16 bits. 
The entire area can be used as desired by the user. 
 
REMARK 
Refer to the Programming Manual (Commands) concerning the GETMEM and 
PUTMEM commands.