To be clear, I don’t actually want/need the AIS messages to be output at 4800. Only the instrument data. Ideally there would be some way to specify which 0183 sentences to output when the output is configured to be 4800 and the rest would be dropped internally by the A031.
My J300X Simrad autopilot is 21 years old (1997) but it does at least have the last, most updated version of the J300X firmware (V9). But that said, it only accepts 4800 NMEA input.
I assume from your response:
1) There is no way to configure which NMEA sentences to output is i.e. no way to indicate that certain 0183 messages should be output and the rest dropped.
2) I assume the behavior will be that when the union of the inputs coming in at 38400 exceeds what can be output at 4800, that sentences will get dropped from the output randomly but proportional to the ratio of input sentence types i.e. in my case, most of the dropped messages will be AIS sentences, but also some instrument messages will get dropped. I predict some will get through but the frequency of seeing an instrument data sentence for anything connected to the NMEA output will be lower than if the AIS messages could be filtered out of the output stream entirely.
3) I hope output sentences won’t get corrupted when the sum of the inputs exceeds 4800 baud. I find it difficult to believe you guys didn’t anticipate/ test this scenario and at a minimum ensure that those messages that do get output are well-formed. That’s how I would build it.
Anyway, I will try and test this and see what happens and let you know when I can.
Cheers.