For other reason, I would like to send a "Commanded address message" to a device(PGN65240). I did create the PGN under the J1939/NMEA parameter. Then under Hardware transmit Device, I try to select the newly created parameters. They are not in the list. Meanwhile the list contain parameters labeled Transmit.J19389.... or Transmit.NMEA2000....
How does a parameter appear on that list? How do you make a parameter an output versus an input?
NMEA parameter transmit
- JZanni
- Posts: 29
- Joined: Tue Oct 12, 2010 3:09 pm
- dwills
- Enovation Controls Development
- Posts: 26
- Joined: Fri Jul 30, 2010 8:27 am
Re: NMEA parameter transmit
The transmit list shows the SPN value, not the PGN, so make sure that SPN values are added to the PGN as well.
Also, the transmit device only transmits at a certain rate, specified in the parameter setup. We don't currently support transmitting on events.
Also, unfortunately we don't currently support transmitting multi-packet messages. I believe that the commanded address PGN requires a multi-packet transmission. This is something that could be added in the future.
Also, the transmit device only transmits at a certain rate, specified in the parameter setup. We don't currently support transmitting on events.
Also, unfortunately we don't currently support transmitting multi-packet messages. I believe that the commanded address PGN requires a multi-packet transmission. This is something that could be added in the future.
- JZanni
- Posts: 29
- Joined: Tue Oct 12, 2010 3:09 pm
Re: NMEA parameter transmit
You Wrote:
J1939.engine1.engine speed
J1939.engine2.engine speed
Which one will be transmitted or I am totally misunderstanding SPN? Further more a variable need to be associated to a PGN. So What PGN will the Transmit device send? All the PGN's which include that specific SPN?
I am not sure I understand what you are saying. I am still new at this so bear with me. I thought SPN's are a method to characterize a data type to enable troubleshooting code. If I have two engines, I will have 2 engine speed variables one per motor both with the same SPN(SPN190).The transmit list shows the SPN value, not the PGN, so make sure that SPN values are added to the PGN as well.
J1939.engine1.engine speed
J1939.engine2.engine speed
Which one will be transmitted or I am totally misunderstanding SPN? Further more a variable need to be associated to a PGN. So What PGN will the Transmit device send? All the PGN's which include that specific SPN?
- dwills
- Enovation Controls Development
- Posts: 26
- Joined: Fri Jul 30, 2010 8:27 am
Re: NMEA parameter transmit
The variables are associated with a particular SPN, adding the SPN to the port for transmit will cause the PGN that contains that particular SPN to be transmitted.
In the below case, with two like devices on the same port, confustion will result. The transmitter will send two 0xf004 PGNs from the same source address with different values. If this is what is needed the second engine should be set up on one of the other can ports, even if they are connected to the same bus. This will allow those receiving the message to differentiate which engine is being refrenced based on the source address.
Also, we typically assume that a SPN only shows up in one PGN definition.
In the below case, with two like devices on the same port, confustion will result. The transmitter will send two 0xf004 PGNs from the same source address with different values. If this is what is needed the second engine should be set up on one of the other can ports, even if they are connected to the same bus. This will allow those receiving the message to differentiate which engine is being refrenced based on the source address.
Also, we typically assume that a SPN only shows up in one PGN definition.