8
5.4 Targets output status (Target Status)
The data message format for NRA24 system target output status is shown as in the table below.
The start sequence (0xAAAA) and termination sequence (0x5555) has been omitted for the
table, where the value of RollCount is continuously cycled between 0-1-2-3-0-1-2-3 ••••••.
When the PC or an external MCU cannot process the output data of the NRA24 sensor in time,
it will cause the received RollCount value to be discontinuous. At this time a faster removal
methods should be found to solve this problem.
Table 9 NRA24 Targets output status message format
Message ID
0x70B
Signal Name
Bit
Resolution
Interval
Type
Comment
NoOfTarget
0..7
1
0…255
u8
The numbers of detected targets
RollCount
8..9
1
0…3
u2
The cycle count is 0-1-2-3
，
and
it change one time per cycle
Rsvd1
10..55
1
-
-
-
Check Sum
56..63
1
0…255
u8
The sum of lower eight bits of
first seven bytes
5.5 Target output information (Target Info)
The target output message format of NRA24 is shown in the following table. The start sequence
(0xAAAA) and the termination sequence (0x5555) have been omitted from the table. When the
radar sensor works normally and detects the target, it outputs the NRA24 system status message,
and then outputs the target output status message, and finally outputs the target output
information message.
Table 10 NRA24 target output information format
Message ID
0x70C
Signal Name
Bit
Resolution
Interval
Type
Comment
Index
0..7
1
0…255
u8
Target ID
Rcs
8..15
-
0…255
u8
The section of radar
reflection
RangeH
16..23
0.01m
0…255
u8
Target distance high 8 bit
RangeL
24..31
0.01m
0…255
u8
Target distance low 8 bit
Rsvd1
32..39
-
-
u8
-
VrelH
40..42
0.05m/s
0..7
u3
-
Rsvd1
43..45
1
1
u3
-
RollCount
46..47
1
-
u2
NRA24 is fixed to 0
VrelL
48..55
0.05m/s
0..255
u8
-
Check Sum
56..63
1dB
0..255
u8
The sum of lower eight bits
of first seven bytes
