FuelTech FTSPARK 1500mJ, Руководство пользователя

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FTSPARK
Priority
ProductID
Product Type
ProductTypeID
Range
Start Finish
Critical ----- 0x0FFF 0x0FFF
Device searching a ProductID (unique
value undefined)
Medium 0x0243 0x4860 0x4861 FTSPARK
MessageID’s list
• 0x0FF, 0x1FF, 0x2FF and 0x3FF – Real time
reading broadcast
0x0FF – Critical priority
0x1FF – High priority
0x2FF – Medium priority
0x3FF – Low priority
Those are the MessageIDs that the FuelTech’s
device will use to transmit its real time readings.
The rate for each broadcast will depend on the
type of data, critical data will be broadcasted
more often. Examples of critical data: Ignition
Cut, Two Step signal, emergency signals, etc.
Examples of high priority data: RPM, ignition
timing, actual injection flow, MAP, TPS, etc.
Values are always transmitted as signed 16 bits
in big-endian byte order.
Statuses are transmitted as big-endian
unsigned 16 bits.
Each real time data will be composed of 4
bytes:
REAL TIME DATA
0-1 2-3
Data identifier
(MeasureID)
Value or status
(big endian)
If a device needs to broadcast more than one
reading at the same time it can do so using a
segmented packet:
Segmented packet PAYLOAD
MEASURE 1
0-1 2-3
MeasureID Value/Stat
MEASURE 2
4-5 6-7
MeasureID Value/Stat
MEASURE 3
8-9 10-11
MeasureID Value/Stat
NOTE
T h e m a x i m u m n u m b e r
of measures that can be
transmitted on segmented
packages are: 1776/4 = 444
Another possibility is to use a CAN standard
data frame to transmit 2 measures at a time, all
the devices in the CAN bus must be capable of
receiving data using all the data layouts.
Segmented packet PAYLOAD
MEASURE 1 MEASURE 2
0-1 2-3 4-5 6-7
MeasureID Value MeasureID Value