X.29 - PAD Messages / Type & Coding

Coding (1): Type and coding of octet 1 of PAD messages.

Coding (2): Type and coding of octet 1 of "error" PAD messages

Coding (3): Type and coding of octet 2 of "error" PAD messages

(1) Type and coding of octet 1 of PAD messages:

Message code

TYPE bits 4 3 2 1

- ------------- --------------------------------------------- --------------

Set PAD message 0 0 1 0

Read PAD message 0 1 0 0

Set and read PAD message 0 1 1 0

Parameter indication PAD message 0 0 0 0

Invitation to clear PAD message 0 0 0 1

Indication to break PAD message 0 0 1 1

Reselection PAD message 0 1 1 1

Error PAD message 0 1 0 1

(2) Type and coding of octet 1 of "error" PAD messages:

Parameter

field code

ERROR TYPE bits 8 7 6 5 4 3 2 1

- ------------- ------------------------------------ ------------------------

0 No additional information 0 0 0 0 0 0 0 0

1 The parameter reference does not exist or has 0 0 0 0 0 0 0 1

not been implemented in the PAD

2 The parameter value is invalid or has 0 0 0 0 0 0 1 0

not been implemented in the PAD

3 The parameter value cannot be altered from the 0 0 0 0 0 0 1 1

current setting

4 The parameter is read-only 0 0 0 0 0 1 0 0

5 The parameter follows an invalid parameter separator 0 0 0 0 0 1 0 1

(3) Type and coding of octet 2 of "error" PAD messages:

Parameter

field code

ERROR MESSAGE bits 8 7 6 5 4 3 2 1

- ------------- ------------------------------------ ------------------------

0 Received PAD message contained less than 8 bits 0 0 0 0 0 0 0 0

1 Unrecognized message code in received PAD message 0 0 0 0 0 0 0 1

2 Parameter field format of received PAD message 0 0 0 0 0 0 1 0

was incorrect or incompatible with message code

3 Received PAD message did not contain an integral 0 0 0 0 0 0 1 1

number of octets

4 Received "parameter indication" PAD message was 0 0 0 0 0 1 0 0

unsolicited

5 Received PAD message was too long 0 0 0 0 0 1 0 1