| Spec | Description |
|---|---|
| S1 | Source module number |
| S2 | Source DADIG block number |
| S3 | Source PCU address |
| S4 | Source loop number |
| S5 | Spare integer |
| S6 | Spare real |
| S7 | Spare boolean |
| Block | Type | Description |
|---|---|---|
| N | Bit | Source reported logic level |
| N+1 | Real | Source extended status |