Edwards STP-iX455, Instruction Manual

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STP-iX455/iXL455 Series Instruction Manual
9-10
O
pe
ra
tio
n
Transmission frame when a message exceeds 255 characters (n = 255, m<=255, k = the
number of transmission blocks):
First 1 2 3 4 5 5+n 5+n+1 5+n+2
Block ASCII Stx 0 0 1 C1
1
C1
n
Etb LRC
Second 1 2 3 4 5 5+n 5+n+1 5+n+2
Block ASCII Stx 0 0 2 C2
1
C2
n
Etb LRC
・・・
Final 1 2 3 4 5 5+m 5+m+1 5+m+2
Block ASCII Stx k Ck
1
Ck
m
Etx LRC
"Stx" is used as a start character of each transmission block; "Etb" is used as an end
character of the transmission block with a message of 255 characters; "Etx" is used
as an end character of the final transmission block (the end character of the
transmission frame).
9.3.3 Control Command (in the RS232/RS485 Single Point Connection)
A control command is used when transmitting a pump operation commands and a
setting change commands to the SIM. The first character of the control command in the
RS232/RS485 single point connection is "Sp" (a space character, HEX code "20"), and
succeeding characters are ASCII characters corresponding to the respective function
code and parameter.
Sp CHR C
1
C
2
C
n
CHR: Function code character, C1 to Cn: Parameter
Parameter (from C
1
to C
n
) serves as 16 bits signed hexadecimal value coded ASCII text.
When a message (a space character, a function code, and parameter) exceeds 255
characters, input "Sp" and CHR only to the top transmission block (the first
transmission block of the transmission frame). It is not necessary to input them to the
2nd and succeeding transmission blocks.
The SIM returns the acknowledgment response character "#" when the control
command is processed normally. If not, the SIM returns the non-acknowledgment
response character "!" and 3 characters of the non-acknowledgment code are added to
"!".
Transmission frame when data is transmitted to one block (a message is less than 256
characters):
Designate the control command on the PC.
←
Less than 256 chr.
→
PC
→
SIM Stx 0
0 1 Sp CHR C
1
C
n
Etx LRC
SIM
→
PC
Ack or Nak
Always assign less than 254 characters (n< 254) to the parameter so that the message is
less than 256 characters.
Then, the preceding SIM->PC character is "Ack", the instructed control command is
executed and the SIM returns the following response.
PC
→
SIM
Ack or Nak
SIM
→
PC Stx 0
0 1 # or ! Etx LRC
The PC transmits "Ack" or "Nak"; then transmits the next command if necessary.