De ARINC 429, Anexo 6:
Label 025, Selected Altitude (BCD)
Five binary coded decimals. Range is up to 50000. Resolution is 1 foot.Bit 29 (MSC) ------------------------------ Bit 11 (LSC)
4 2 1 | 8 4 2 1 | 8 4 2 1 | 8 4 2 1 | 8 4 2 11 0 0 | 0 0 0 1 | 0 0 0 0 | 0 0 0 0 | 0 0 0 0
The above line codes to 41000 ft.
Note: Negative sign is annunciated in the sign/status matrix.Label 102, Selected Altitude (BNR) 16 bits of data. Range of 65536. Resolution (value of LSB) is 1 foot.
Bit 28 (MSB)------------------- Bit 13 (LSB) (Bits 12-11 are set to 0)
1 0 1 0 0 0 0 0 0 0 1 0 1 0 0 0The above line codes to 41000 ft.
Note: Negative values are encoded as the two’s complements of positive values and the negative sign is annunciated in the sign/status matrix.