Text Packet Format; Stx; No. Bytes; Command - Nordson EFD Ultimus V Manuel Utilisateur

Annexe B — Protocole RS-232 (suite)

2.3 Text Packet Format

Each text packet contains the following information and is structured as shown below:
[STX] [No. Bytes] [Command] [Data] [Checksum] [ETX]
NOTE: EOT ( 0x04 ), ENQ
nothing else added to them.

2.3.1 STX

Every text packet begins with this Start of Text control character (hexadecimal
below.
NOTE: The Start of Text control character (
EOT ( 0x04 ), or NAK ( 0x15

2.3.2 No. Bytes

The No. Bytes (Number of Bytes) part of the text packet is the number of characters in the Command and Data parts
of the packet. This value is expressed as a 2-digit hexadecimal with its characters encoded as ASCII.
EXAMPLES:
• If Command is four characters and Data is six characters, the No. Bytes decimal value is 10. In the text packet,
No. Bytes will be 0x0A
ASCII as 0x30 , 0x41
• If the number of Command plus Data characters is 16, No. Bytes will be
character value for No. Bytes will be

2.3.3 Command

The Command part of the text packet is next. The list of available Commands is contained in "RS-232 Commands"
on page 50. A Command is up to four characters long. If a Command does not contain four characters, the
remaining characters must be the ASCII space character (

2.3.4 Data

The Data part of the text packet is after the Command. The Data part can be from 0 to 251 characters long,
depending on the Command. The Data part is transmitted as ASCII characters, typically a decimal representation of
a number.
www.nordsonefd.com/fr EFDEU-South@nordson.com
( 0x05 ), ACK ( 0x06 ), and NAK
STX / 0x02
) because these are single-byte control characters, not text.
in hexadecimal, so the ASCII character value for No. Bytes will be
.
10 , which is encoded as
+33 (0) 1 30 82 68 69 Les services et les points de vente des systèmes de dosage Nordson EFD sont présents dans le monde entier.
Doseur de Fluide Haute Précision Ultimus V
( 0x15 ), and are single-byte control characters, with
0x02
) is not added when sending
0x10 in hexadecimal, so the ASCII
0x31 , 0x30 .
0x20 ). The Command is transmitted as ASCII characters.
or CTRL+B), except as noted
ENQ ( 0x05 ), ACK ( 0x06 ),
0A . This is encoded in
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