TOHO ELECTRONICS TTX-700 - Manual (Page 27)

6.8 Composition of an ASCII request message (transmitted from a high-level
computer to this product)
n For the codes a) through g), see "6.10. Description of ASCII codes."
6.8.1 Composition of a read request message
a) Start code “:”
b) Slave address “1” , “B”
c) Function code “0” , “3”
High level “0” , “0”
d) Register address
Low level “0” , “0”
First register address
High level “0” , “0”
e) Number of registers
Low level “0” , “2”
2 to 100 (even number only)
f) LRC “E” , “0”
g) End code CR, LF
6.8.2 Composition of a write request message
a) Start code “:”
b) Slave address “0” , “3”
c) Function code “1” , “0”
High level “0” , “0”
d) Register address
Low level “C” , “0”
First register address
High level “0” , “0”
e) Number of registers
Low level “0” , “2”
Fixed at 2
h) Number of data items “0” , “4” Number of registers
×
2
High level “0” , “0” ③
Data for the first register
(a low-level word)
Low level “6” , “F” ④
High level “0” , “0” ①
i)
Data for the first register + 1
(a high-level word)
Low level “0” , “0” ②
When writing ①, ②, ③, and
④ H in the data, write them in
the order described on the
left-hand side. (① represents 1
byte.)
f) LRC “E” , “0”
g) End code CR, LF
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