Cygnus 1 User Manual

Introduction
14
Valid-Reading packet arrangement
7 byte sequence :
1. SOH [hex 01]
2. Status-byte
3. Data-byte 0
4. Data-byte 1
5. Data-byte 2
6. Data-byte 3
7. ETB [hex 17]
No-Reading packet arrangement
3 byte sequence :
1. SOH (hex 01)
2. Status Byte
3. ETB (hex17)
Status-byte structure
decodes into bit-fields :
¾ bit 7 - ms Cygnus Gauge type HI = Mark2+ [default]
[LO = Mark1 – not used]
¾ bit 6 Reading Resolution HI = Hi-Resolution [default]
¾ bit 5 Measurement Units LO=Metric [default]
HI = Imperial
¾ bit 4 Reading Range HI = Hi-Range
¾ bits 3, 2 Echo Count 0 to 3 Echoes found
¾ bit 1 Calibration HI = Remote [default]
LO = Local
¾ bit 0 - ls No-Reading flag HI = No-Reading
LO = Valid-Reading
Data-bytes arrangement
¾ The four data bytes are ASCII-encoded, decimal thickness value
¾ Data byte 0 is most-significant
¾ Leading-zeroes are replaced by ascii Space [hex 20]
¾ Decimal points are implied from the Status-byte – Units, Resolution and Range bits :
Reading-type Hi-Range Lo-Range
Ö Imperial, Lo-Resolution x x . x x x . x x x
Ö Metric, Lo-Resolution x x x . x x x x . x
Ö Imperial, Hi-Resolution x x . x x x . x x x
Ö Metric, Hi-Resolution x x x . x x x . x x

Cygnus 1 Specifications

General

Brand	Cygnus
Model	1
Category	Measuring Instruments
Language	English