Fundamental nct binary message block format, Message application, Message query – NavCom LAND-PAK Rev.N User Manual
Page 15: Message organization, Parameter length

Technical Reference Manual Rev. N
Blk = All;
Blu = IOP w/Internal Radio
;
Red = IOP & LBM
;
Grn = Engine only
13
Fundamental NCT Binary Message Block Format
Message Application
All messages listed in this document are contained within the NCT-2000D and NCT-2100D.
This manual specifically relates to software ensemble version 5.1.13.
Software ensemble versions 5.1.13, 5.1.6, and 4.2.20 are not compatible with the NCT-
2000D. NCT-2000D equipped receivers will use 3.2.9 software and may be upgraded to
the NCT-2100D for a fee. Please contact a NavCom dealer or NavCom Sales for more
information. Products with serial numbers lower than 5000 contain the NCT-2000D, unless
otherwise noted. Integrated models can determine the receiver type via the AE message.
Digital serial numbers <40,000 are model NCT-2000D engines.
Message blocks in blue relate specifically to NCT-2000D/NCT-2100D products
(“Engine” in footnote) that are coupled with an I/O board and internal 2.4GHz radio.
Message blocks in red relate specifically to NCT-2000D/NCT-2100D products that
are coupled with an I/O board and a LBM (L-band module).
Message blocks in green relate specifically to NCT RT-series or SF-series products.
They remain constant regardless of product type, but not meant to be used for any
NCT-2000D/NCT-2100D OEM application.
Message Query
Each message block may be queried by applying a schedule of 0 using the message block 0x20.
Message Organization
NavCom product messages are composed of a variety of 1 to 8-bit byte segments, defined as:
Parameter Length:
S08
char (1 Byte; -128 to 127, MSB indicates sign)
U08
Unsigned char (1 Byte; 0 to 255)
S16
short (2 Bytes)
U16
Unsigned short (2 Bytes)
S24
Integer (3 Bytes; see note)
U24
Unsigned Integer (3 Bytes)
S32
Integer (4 Bytes)
U32
Unsigned Integer (4 Bytes)
R32
Floating Point (4 Bytes)
R64
Floating Point (8 Bytes)
U24 = U08 low, U08 middle, and U08 high.