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Control field, Table 5: coding of the control field – Siemens Mux_guide_v06 User Manual

Page 19

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Multiplexer User's Guide
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Mux_guide_v06

Page 19 of 36

30.06.2004

4.2.3 Control field

The control field contains control information to define the frame.

Frame

Type

1 2

3 4

5 6

7 8

SABM

(set asynchronous
balanced mode)

1 1

1 1

P/F

1

0 0

UA

(unnumbered
acknowledgement)

1 1

0 0

P/F

1

1 0

DM

(disconnected mode)

1 1

1 1

P/F

0

0 0

DISC

(disconnect)

1 1

0 0

P/F

0

1 0

UIH

(unnumbered information
with header check)

1 1

1 1

P/F

1

1 1


P/F: Poll/Final bit
Commands: P = 1, Responses: F = 1
For each DLCI, only one frame with P = 1 may ever be expected.

Table 5: Coding of the control field