NAiS FP Series, User Manual

Page: 176 / 326

FP
Σ
9.2 Overview of Communication with External Devices
9 - 9
Sample program for data transmission
This program transmits the character “ABCDEFGH” to external device using COM.1
port.
Data transmission command
The internal relay “R10” is turned on at the tim-
ing of the transmission condition “R0”.
are sent from the COM.1 (K1) port.
Data conversion
The character “ABCDEFGH” is converted to an
ASCII code, and written to DT101 to DT104.
Data transmission
The data in the transmission buffer is sent from
the COM. 1 port. Starting from DT100
the contents of 8 bytes
R10
R10
R0
R10
DF
F95 ASC , M ABCDEFGH , DT101
F159MTRN ,DT 100 , K8 ,K1
Figure 170: FP
Σ
Sample program for data transmission
The program described above is executed in the following sequence.
(1) “ABCDEFGH” is converted to an ASCII code and stored in a data register.
(2) That data is sent from the COM. 1 port using the
F159 (MTRN) instruction.
Explanatory diagram
The character is converted to ASCII code
and the data is stored in transmission buffer.
“H4142434445464748”
FP
Σ
Data register (DT)
Device with
RS232C port
Data transmission using
F159 (MTRN) instruction
Transmission
buffer
“ABCDEFGH”
Figure 171: FP
Σ
Data transmission explanatory diagram
Explanation of data table
This is used as a data table for transmission, starting at the data register specified in
“S”.
Figure 172: FP
Σ
Data table for transmission
Use an F0(MV) or F95(ASC) instruction to write the data to be transmitted to the
transmission data storage area specified in “S”.
At the beginning of transmission,
the number of bytes to be transmitted is set.
At the end of transmission, “0” is set.
The circled numbers indicate the order of
transmission.
Transmission data
storage area
S
S+1
S+2
S+n
1 2
3 4