Edwards STP-iS1607 Series User Manual

STP-iS1607 Series Turbomolecular Pump
MT-94E-001-C
Page 82
5
SERIAL COMMUNICATION PROTOCOL
Table 20 shows ASCII characters being used in the transmission control, error control and
handshake in the application layer.
ASCII
character
HEX
code
Function
Transmission layer
Stx
02
Transmission block start character
Etx
03
Transmission frame end character
Etb
17
Transmission block end character
Ack
06
Acknowledgment response
Nak
15
Non-acknowledgment response
@
40
Network frame ID character
Application layer
#
23
Acknowledgment response
!
21
Non-acknowledgment response
Table 20 - Transmission control characters
5.3.2 Standard transmission frame (in the RS232/RS485 single point connection)
The transmission frame has a single block or multiple transmission blocks. The transmission block
consists of a start control character, data block No. (3 digits), a message (up to 255 characters), an
end control character, and a checksum (LRC). The following table shows the transmission frame
where the message transmission character string is C
n
.
Transmission frame when a message is below 255 characters (n<=255):
1
2
3
4
5
5+n
5+n+1
5+n+2
ASCII
Stx
0
0
1
C
1
C
n
Etx
LRC
"Stx" and "Etx" are used as a start and an end character of the transmission frame, respectively.

Edwards STP-iS1607 Series Specifications

General

Brand	Edwards
Model	STP-iS1607 Series
Category	Water Pump
Language	English