Time Reference Message Fields
The Time Reference message is used to provide a midnight reference point for recipients of the feed. It is sent whenever the system starts up and when the system crosses a midnight boundary. All subsequent Time messages for the same unit will the use the last Midnight Reference until another Time Reference message is received for that unit. The Time Reference message includes the Trade Date, so most other sequenced messages will not include that information.
Time Reference messages will be included in a spin response.
| Field Name | Offset | Length | Type/(Value) | Description |
|---|---|---|---|---|
| Length | 0 | 1 | Binary | Length of this message including this field. |
| Message Type | 1 | 1 | 0xB1 | Time Reference message |
| Midnight Reference | 2 | 4 | Binary | Midnight Central Time reference time for subsequent Time messages, expressed as number of whole seconds since the Epoch (Midnight January 1, 1970 UTC). |
| Time | 6 | 4 | Binary | Number of whole seconds elapsed since the start of the current Central Time calendar day, derived by converting the current Central wall clock time (HH:MM:SS) to seconds. On Daylight Saving Time transition days, Time reflects wall clock seconds and does not adjust for the UTC offset change. On a DST spring-forward day, the maximum value will be 82,799 (23 hours). On a DST fall-back day, values between 3,600 and 7,199 will appear twice. Recipients requiring unambiguous absolute timestamps should use Epoch Time (where available) or Midnight Reference in the Time Reference message. |
| Time Offset | 10 | 4 | Binary | Nanosecond offset from last unit timestamp. |
| Trade Date | 14 | 4 | Binary Date | Current Trade Date |
| Total Length = 18 bytes | ||||