Watson Industries, Inc.
ADS-C232-3AD Rev A 10/25/2017
20
Appendix C
Binary Data Format
All of the data words have a high sign bit, but the delimiter byte is an ASCII carriage return character that has a low
sign bit. One word per output parameter.
Example: Unit is sending out Bank, Elevation, X Angular Rate, & Y Angular Rate
The Unit is seeing these conditions:
Binary Output Format:
The Carriage return byte is the only byte which has a value less than 128 (0x80). This is the Synchronizing Byte.
7
6
5
4
3
2
1
0
7
6
5
4
3
2
1
0
Data Word
MSB
LSB
Bit 7 of the MSB is set to 1. Bits 6 to 0 of the MSB are the upper 7 bits of the data. (sign plus 6 bits of data)
Bit 7 of the LSB is set to 1. Bits 6 to 0 of the LSB are the lower 7 bits of the data.
As the data words are received, the LSB is shifted left to shift out the 7th bit (always set to 1). The MSB is then
connected to the LSB as a 16-bit word. This word is then shifted left to shift out the 7th bit (always set to 1). What
remains is a signed fractional word with a resolution of 13 bits plus a sign bit.
To convert binary data:
Split each word into two bytes:
Remove the most significant bit from each byte:
Bank
Elevation
X Rate
Y Rate
15.0˚
-5.0˚
10.2˚/s
-3.1˚/s
Word1
Word2
Word3
Word4
<CR> byte
0x85AA
0xFE9C
0x83A1
0xFF81
0x0D
Bank
Elevation X Rate
Y Rate
0x85AA
0xFE9C
0x83A1
0xFF81
Bank
Elevation X Rate
Y Rate
0x85
0xAA
0xFE
0x9C
0x83
0xA1
0xFF
0x81
Bank
Elevation X Rate
Y Rate
0x05
0x2A
0x7E
0x1C
0x03
0x21
0x7F
0x01
