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This appendix defines a set of exceptions that may occur during various sequencing processes as defined in the sequencing pseudo code update (refer to Appendix C).
Exceptions are reported to the LMS through the Overall Sequencing Process (OP). Each exception is identified by a code that indicates in which sequencing process the exception occurred – this is the first portion of the exception code, immediately prior to the “-” character.
The set of exceptions listed below is only intended to enumerate the events that may occur while processing the normative sequencing pseudo code; it is not an exhaustive set. In particular, this list does not include any delivery, launch or take-away exceptions, which may occur after sequencing has identified the next activity for delivery.
An implementation of SCORM sequencing is not required to implement all or any of the exceptions listed below, and an implementation is free to provide any additional exceptions as it sees fit. However, it is recommended that an LMS utilize the exceptions listed below (and any additional ones provided by its implementation) to minimize interference and distractions to the learning experience.
Table Appendix D – Sequencing Behavior Pseudo Code Exceptions
# | Code | Description |
1 | NB.2.1-1 | Current Activity is already defined / Sequencing session has already begun |
2 | NB.2.1-2 | Current Activity is not defined / Sequencing session has not begun |
3 | NB.2.1-3 | Suspended Activity is not defined |
4 | NB.2.1-4 | Flow Sequencing Control Mode violation |
5 | NB.2.1-5 | Flow or Forward Only Sequencing Control Mode violation |
6 | NB.2.1-6 | No activity is “previous” to the root |
7 | NB.2.1-7 | Unsupported navigation request |
8 | NB.2.1-8 | Choice Exit Sequencing Control Mode violation |
9 | NB.2.1-9 | No activities to consider |
10 | NB.2.1-10 | Choice Sequencing Control Mode violation |
11 | NB.2.1-11 | Target activity does not exist |
12 | NB.2.1-12 | Current Activity already terminated |
13 | NB.2.1-13 | Undefined navigation request |
14 | TB.2.3-1 | Current Activity is not defined / Sequencing session has not begun |
15 | TB.2.3-2 | Current Activity already terminated |
16 | TB.2.3-3 | Cannot suspend an inactive root |
17 | TB.2.3-4 | Activity tree root has no parent |
18 | TB.2.3-5 | Nothing to suspend; No active activities |
19 | TB.2.3-6 | Nothing to abandon; No active activities |
20 | TB.2.3-7 | Undefined termination request |
21 | SB.2.1-1 | Last activity in the tree |
22 | SB.2.1-2 | Cluster has no available children |
23 | SB.2.1-3 | No activity is “previous” to the root |
24 | SB.2.1-4 | Forward Only Sequencing Control Mode violation |
25 | SB.2.2-1 | Flow Sequencing Control Mode violation |
26 | SB.2.2-2 | Activity unavailable |
27 | SB.2.4-1 | Forward Traversal Blocked |
28 | SB.2.4-2 | Forward Only Sequencing Control Mode violation |
29 | SB.2.4-3 | No activity is “previous” to the root |
30 | SB.2.5-1 | Current Activity is defined / Sequencing session already begun |
31 | SB.2.6-1 | Current Activity is defined / Sequencing session already begun |
32 | SB.2.6-2 | No Suspended Activity defined |
33 | SB.2.7-1 | Current Activity is not defined / Sequencing session has not begun |
34 | SB.2.7-2 | Flow Sequencing Control Mode violation |
35 | SB.2.8-1 | Current Activity is not defined / Sequencing session has not begun |
36 | SB.2.8-2 | Flow Sequencing Control Mode violation |
37 | SB.2.9-1 | No target for Choice |
38 | SB.2.9-2 | Target activity does not exist or is unavailable |
39 | SB.2.9.3 | Target activity hidden from choice |
40 | SB.2.9-4 | Choice Sequencing Control Mode violation |
41 | SB.2.9-5 | No activities to consider |
42 | SB.2.9-6 | Unable to activate target; target is not a child of the Current Activity |
43 | SB.2.9-7 | Choice Exit Sequencing Control Mode violation |
44 | SB.2.9-8 | Unable to choose target activity – constrained choice |
45 | SB.2.9-9 | Choice request prevented by Flow-only activity |
46 | SB.2.10-1 | Current Activity is not defined / Sequencing session has not begun |
47 | SB.2.10-2 | Current Activity is active or suspended |
48 | SB.2.10-3 | Flow Sequencing Control Mode violation |
49 | SB.2.11-1 | Current Activity is not defined / Sequencing session has not begun |
50 | SB.2.11-2 | Current Activity has not been terminated |
51 | SB.2.12-1 | Undefined sequencing request |
52 | SB.2.13-1 | Current Activity is not defined / Sequencing session has not begun |
53 | DB.1.1-1 | Cannot deliver a non-leaf activity |
54 | DB.1.1-2 | Nothing to deliver |
55 | DB.1.1-3 | Activity unavailable |
56 | DB.2-1 | Identified activity is already active |