I found an example for a multipacket transmission on the web and you can find it attached to this post. on page 17 and 18 it is described how to send the multiple packet messages. You could use the frame api or the channel api which brings allready J1939 ID support in MAX to create the frame content.
My guess is that this 00ECFF is the PGN and has the source address added already. Besides that it is shown LSB first. So if the source address is FF and the PGN is 0xEC00 that translates to 0x00ECFF.
The same is true for the other PGNs: 0xEB00 converts to 0x00EBFF with source address FF and LSB first.
Would it be possible to share the code you have developed for multiframe message(BAM and TP.DT)
If not,please give a brief on the same
If you are trying to read active DTC codes, and you have more than one DTC on the node you are communicating with, it will want to send you a BAM, prior to the spew of packets holding the array of DTCs.
I do not know if BAM messaging or TP is worked into the example J1939 driver provided as an example by NI.... if not, you could easily get the SAE spec and add code to their example.
DMC recently developed a set of J1939 protocol drivers for LabVIEW which are based on the NI-CAN channel API. The drivers are written in LabVIEW just like the example, but provide functions at a layer above the base CAN channel API layer. This allows the simultaneous capture of data from both J1939 packets which are simple broadcast CAN frames, or more complex transport using BAM, including extended data frames.
Their development was not easy, but definately do-able with some extra programming time.
In SAE J1939-21 Sec. 5.10.4 Figure 16 on p. 35
PDU specified field: Destination Address (Global (DA = 255) for TP.CM.BAM data transfers) (Global not allowed for RTS/CTS data transfers)
Since 0xEC < 0xF0 (240) the PDU specified field is a destination address instead of a Group Extension.
The Destination address of 0xFF (255) means Global.
I would guess the original j1939 message has a PDU Format >= 0xF0 (240)
otherwise the 0xFF would be the Destination address you provided.