Toho Electronics TTM-200 Series, Operation Manual, Communications

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6.8 Composition of an ASCII request message (transmitted from a high-level
computer to this product)

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
“0” , “1”
c) Function code
“0” , “3”
d) Register address
High level
“0” , “0”
First register address
Low level
“0” , “0”
e) Number of registers
High level
“0” , “0”
Fixed at 2
Low level
“0” , “2”
f) LRC
“F” , “A”
g) End code CR, LF
6.8.2 Composition of a write request message
a) Start code
“:”
b) Slave address
“0” , “1”
c) Function code
“1” , “0”
d) Register address
High level
“0” , “1”
First register address
Low level
“0” , “0”
e) Number of registers
High level
“0” , “0”
Fixed at 2
Low level
“0” , “2”
h) Number of byte items
“0” , “4”
Register

2
i)
First register data
(a low-level word)
High level
“0” , “0”
③
Data composition is
①
,
②
,
③
,
and
④
H. (
①
represents 1
byte.)
Low level
“0” , “0” ④
First register data
(a high-level word)
High level
“0” , “0”
①
Low level
“0” , “0”
②
f) LRC
“E” , “8”
g) End code CR, LF
6.8.3 Composition of a store request message
a) Start code
“:”
b) Slave address
“0” , “1”
c) Function code
“1” , “0”
d) Register address
High level
“2” , “0”
First register address
Low level
“0” , “E”
e) Number of registers
High level
“0” , “0”
Fixed at 2
Low level
“0” , “2”
h) Number of byte items
“0” , “4”
Register

2
i)
First register data
(a low-level word)
High level
“0” , “0”
The data about the storage of settings
is arbitrary.
Low level
“0” , “0”
First register data
(a high-level word)
High level
“0” , “0”
Low level
“0” , “0”
f) LRC
“B” , “B”
g) End code CR, LF