Roche Cobas C 311 - Communication Data Structure

Roche/Hitachi cobas c 311 analyzer ASTM communication protocol
Communication data structure
Roche Diagnostics May 2011
Host Interface Manual – Version 1.3 D-2
ASTM Communication Protocol
cobas c 311 analyzer employs ASTM communication
protocol.
Communication data structure
ASTM communication protocol consists of three layered data
structure such as message, record, and frame. In the
application layer, data is communicated by message. Further,
data is communicated by frame actually in the data link layer.
Data structure of a frame varies by protocol.
A message consists of several records. A record consists of
one or more frames. If a message exceeds 240 bytes, a
frame is divided into middle frames and a last frame. [ETB] is
used for the middle frame and [ETX] is used for the last frame.
[
Messa
g
e
]
[
Record
]
[
Frame
]
Communication
Creating Message
A
nalyzing Message
[
ETX
]
[ETB]
[
ETB
]
[
ETB
]
[ETB]
[ETB]
Application Layer Data Link Layer Presentation Layer