WATSON INDUSTRIES DMS-S605, Руководство пользователя

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Watson Industries, Inc. DMS-SGP02 Rev K 03/22/2018
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Example 3: The Unit is seeing these conditions:
Binary output Format:
Word 1 & 2 form the 4 byte Latitude
Word 3 & 4 form the 4 byte Longitude
Word 5 is the 2 byte Altitude
Word 6 is the 2 byte Ground Track Velocity
7 6 5 4 3 2 1 0 7 6 5 4 3 2 1 0
Data Word
MSB LSB
For four byte (2 words – 1 long word) data:
Bit 7 of the High Byte is set to 1. Bits 6 to 0 of the High Byte are the upper 7 bits of the data. (sign plus 6 bits
of data). Bit 7 of the 2
nd
Byte is set to 1. Bits 6 to 0 of the 2
nd
Byte are the next 7 bits of the data. Bit 7 of the
3
rd
Byte is set to 1. Bits 6 to 0 of the 3
rd
Byte are the next 7 bits of the data. Bit 7 of the LSB is set to 1. Bits 6
to 0 of the LSB are the lower7 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 3
rd
byte is
then connected to the LSB as the lower 16 bit word. This word is then shifted left to shift out the 7th bit
(always set to 1). The 2nd byte is connected to the lower word. These 3 bytes are then shifted left to shift out
the 7th bit (always set to 1). The MSB is then connected to the 3 lower bytes as a 32 bit long word. This long
word is then shifted left to shift out the 7th bit (always set to 1). What remains is a signed fractional long
word (32 bits) with a resolution of 27 bits plus a sign bit.
For two byte (1 word) data:
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:
Latitude Longitude Altitude Velocity
44.86403
or
4451.84233,N
-91.46668
or
09126.00199 W
894 Ft 8.01 kph
Word1 Word2 Word3 Word4 Word5 Word6 <CR> byte
0x8FF9 0xE7F7 0xDFBD 0x9FF9 0x83BF 0x81A4 0x0D
Latitude Longitude Altitude Velocity
0x8FF9 0xE7F7 0xDFBD 0x9FF9 0x83BF 0x81A4