Appendix 7
EBU recommendations for the recording of information in the user bits
Although the EBU recognizes that its member organizations can freely use the binary groups in any way, nevertheless a number of specific uses have been devised by individual organizations, for internal use. The EBU has documented these uses for the benefit of all member organizations. Chapter 5 covered one of these uses (panscan data in user bits).
In the UK the BBC has devised a means of carrying date information in the user bits in dd, mm, yy form. The date is normally changed at midnight local time, taking any summer time into account. Each digit of the date is coded in BCD in the following manner:
| Binary group 1 | Reserved | All bits set to zero |
| Binary group 2 | Units of days | 4 bits, LSB in bit 12 |
| Binary group 3 | Units of months | 4 bits, LSB in bit 20 |
| Binary group 4 | Tens of days | 2 bits, LSB in bit 28 |
| Tens of months | 1 bit, bit 30. Bit 31 set to zero | |
| Binary group 5 | Reserved | All bits set to zero |
| Binary group 6 | Units of years | 4 bits, LSB in bit 44 |
| Binary group 7 | Reserved | All bits set to zero |
| Binary group 8 | Tens of years | 4 bits, LSB in bit 60 |
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