dataTaker CANgate, Руководство пользователя

Страница: 13 / 42

UM-0086-A2
CANgate User’s Manual Page 13
Memory Slot Commands and Protocol Hierarchy
CAN networks can use a number of different higher level communications protocols. The following diagram illustrates the
protocols used by each type of memory slot.
CANgate protocol hierarchy
As can be seen, the RECV, RECVE, SEND and SENDE memory slot types operate on raw CAN messages. A raw CAN
message consists of an 11 or 29 bit identifier, plus 8 bytes of data.
RQST memory slots allow parameters to be requested using standard automotive OBD (On Board Diagnostics) requests.
The ISO 15765-2 network layer protocol is responsible for breaking up the request and response messages into multiple
CAN frames, if required.
RECVJ and RQSTJ memory slots allow broadcast and requested parameters to be read from a J1939 network. J1939 also
incorporates a network layer which can break long messages up into multiple CAN frames.
Finally, GPS memory slots allow fields of interest to be extracted from the NMEA-0183 data stream produced by a GPS
device.
Entering Commands
CANgate memory slots and other settings are configured by sending textual commands via the host port. The available
commands are detailed in the Command Reference
(P16)
.
If CANgate is directly connected to host computer then these commands can be entered using a terminal program (eg.
DeTransfer ).
If CANgate is connected to the serial sensor port on a DT80/DT800 series data logger then the logger would be programmed
to transmit commands and receive data using the
1SERIAL channel type. Refer to the logger User Manual for more details.
CANgate commands are not case sensitive.
Most commands have a set number of space-separated
parameters . All parameters must be specified, unless a parameter
is marked as optional.
A parameter's data type will be specified as either:

floating point – enter a decimal value, eg. 1.25 , -4 , 0.9907

integer – enter a decimal or hexadecimal value, eg. 2309 , 0xff07 , -10 (hexadecimal values are prefixed by 0x )
RECV RECVE
SEND SENDE
NMEA-0183
GPS RQST RECVJ
RQSTJ
ISO 14230-3 / OBD-II
Diagnostic Services
Application Layer
SAE J1939-71
Vehicle Application Layer
ISO 15765-2
Network Layer
SAE J1939-21
Data Link / Network Layer
CAN 2.0B PROTOCOL / ISO 11898-2
Data Link / Physical Layer
GPS PORT CAN PORT 2 CAN PORT 1