Hi guys, I know the Pro 900 XSC has about 4x the range of the Pro 900, but that it's data rate is only 9.6kbps.Is this enough for full duplex telemetry and on the fly route updates from the mission…Continue
I'm just getting into the UAV and Multicopter platforms for a change from other platforms and I've picked a fairly straight forward Quadcopter frame. Then in a photo link to a news story I saw the…Continue
"I get what you're saying, and if you removed it all together from the radio it would free up room, otherwise a selective routine on the radio would take up even more space.
It'd also mean that the application would need a change to support…"
"What I'm trying to say is that there's no point in error correction on multiple layers.
We could have error detection/correction on the physical, transport, and application layers, but each extra one just wastes bandwidth and…"
"Although some of it may be time critical, other things would be critical regardless of it it arrived late. If a stop command was required and it wasn't re-transmitted, a delay would clearly be preferable to missing it all together.…"
"That's good to know. I haven't had time to poke around in the code yet.
I would think software flow control would work fine. I also wonder about how necessary the error detection/correction is. Mavlink already has error…"
"Unfortunately I don't think I'd be very well suited to freeing up resources as I've never worked with code for radios or communications protocols. That's why I've always used Xbee's as they do the hard work for…"
"There is certainly scope to improve memory usage - the serial rx buffer is around 2k of ram at present!.
At the moment, the code is structured such that the buffer size is 2^n. The buffer size on XBee's IIRC is in the order of a…"
"These radio's are open source aren't they? Surely amongst everyone there should be some optimisations that can be made to free up a little more RAM & flash?
If there's no hope I'll just use some Xbee 900's and hope…"
"Encryption is certainly needed and should be one of the core features of the data stream protocol.
91 bytes of ram and 3156 bytes of flash for a complete encryption solution is a trivial amount.
The Si1000 chip has 64kb of flash and 4.25k of ram.
"Since we've got somewhere between 4 and 10 free bytes of ram at present ("8051: Everything is Global!" *sigh*) implementing new functionality alongside SiK is not really feasible.
Encryption on the RCLink? Yikes, guess I'd better…"
"What I meant was that SiLabs has an encryption library ready to go. It would not be difficult to implement it if the memory is available.
I think the current firmware uses most of the memory available, so it would require some choices on…"
"Oh....Jake made it sound like encryption could happen fairly easily/quickly on the current modems. I'm guessing you have no ETA on these new modems?
Perhaps I'll purchase some Xbee Pro 900's for the interim as I use them on…"