Measurement Computing DBK70 - Manual (Page 50)

5-20 919092 PidPRO & PidPRO+
Source Channel
This field specifies the source channel setting to select the appropriate network interface and protocol.
In the case of ISO9141, the different Source Channel settings enable unique initialization sequences for
establishing communications on a working network. Since the DBK70’s physical ISO9141 interface
cannot support more than one initialization sequence concurrently, make sure that all the configured
channels that are using the ISO9141 interface have the same Source Channel assignment.
In the case of CAN, the different Source Channel values enable different physical transceivers on the CAN
interface card. Since the DBK70’s physical CAN interface cannot support more than one transceiver
concurrently, make sure that all the configured channels that are using the CAN interface have the same
Source Channel assignment.
Network Type
Source
Channel
Value
Special Case
J1850-PWM 1 Single ECM *
Source
Channel
Value
J1850 VPW 3
ISO9141:
Standard ISO9141 2 250 k baud
ISO14230-4 7 or 9
ISO with no initialization 8 500 k baud
CAN:
ISO11519-2 4
ISO11898 4 25 k baud
ISO11898/3 4 through 4
ISO11992 5 1.0 M baud
J1939 4
J2284 4
J2411 6
OBD CAN 9
* In Single ECM mode, choosing a source channel value of “9” tells the DBK70 to cycle on two
communication speeds [250 k baud or 500 k baud]. Choosing a source channel value of “4” when
connected to a single ECM tells the DBK70 to cycle through all known communication speeds, i.e.,
25 k baud through 1.0 M baud.
Message Send Rate
Some modules will not broadcast the desired information on the network unless the information is
explicitly requested. In these cases, the Message Send Rate field [the same as Update Rate in Summary
View] must contain a number above 0 representing the number of milliseconds between times the DBK70
will issue the request message found in the message fields (Msg 1 and Msg 2). If the Message Send Rate is
0, no request message will be sent.
If it is desired that the message in the Message fields be transmitted one time, rather than periodically, set
the Message Send Rate field to a value of -1. This will cause the DBK70 to send the message in the
message field when it is powered on and/or if the timeout occurs.
Note that vehicle manufacturers have limits on the rate at which outside messages can be sent onto the data
buses of their vehicles. This rate may vary from vehicle to vehicle within the same manufacturer and same
model year. For legislated PIDs on J1850, an aggregate request rate of about 10Hz should not be
exceeded. For ISO 9141, the aggregate update rate should not exceed about 8Hz. This means that for
J1850, all the enabled channels in the DBK70 should not collectively issue request messages faster than
10Hz.