
May
2015
WorkHorse H-ADCP Operation Manual
Page 200
EAR-Controlled Technology Subject to Restrictions Contained on the Cover Page.
Header information is the first item sent by the H-ADCP to the output buffer. The H-ADCP always sends
the Least Significant Byte (LSB) first.
Table 35:
Header Data Format
Hex Digit
Binary Byte
Field
Description
1,2
1
HDR ID / Header ID
Stores the header identification byte (7Fh).
3,4
2
HDR ID / Data Source
ID
Stores the data source identification byte (7Fh for the H-ADCP).
5-8
3,4
Bytes / Number of
bytes in ensemble
This field contains the number of bytes from the start of the current ensemble up to,
but not including, the 2-byte checksum (Figure 54).
9,10
5
Spare
Undefined.
11,12
6
No. DT / Number of
Data Types
This field contains the number of data types selected for collection. By default,
fixed/variable leader, velocity, correlation magnitude, echo intensity, and percent
good are selected for collection. This field will therefore have a value of six (4 data
types + 2 for the Fixed/Variable Leader data).
13-16
7,8
Address Offset for
Data Type #1 / Off-
set for Data Type #1
This field contains the internal memory address offset where the H-ADCP will store
information for data type #1 (with this firmware, always the Fixed Leader). Adding “1”
to this offset number gives the absolute Binary Byte number in the ensemble where
Data Type #1 begins (the first byte of the ensemble is Binary Byte #1).
17-20
9,10
Address Offset for
Data Type #2 / Off-
set for Data Type #2
This field contains the internal memory address offset where the H-ADCP will store
information for data type #2 (with this firmware, always the Variable Leader). Adding
“1” to this offset number gives the absolute Binary Byte number in the ensemble
where Data Type #2 begins (the first byte of the ensemble is Binary Byte #1).
21-24 thru
2n+13 to
2n+16
11,12 thru
2n+5, 2n+6
Address Offsets for
Data Types #3-n /
Offset for Data Type
#3 through #n
These fields contain internal memory address offset where the H-ADCP will store in-
formation for data type #3 through data type #n. Adding “1” to this offset number
gives the absolute Binary Byte number in the ensemble where Data Types #3-n begin
(first byte of ensemble is Binary Byte) #1).