Thanks. that answers the “WTF… you can’t split UART” question. still worried about how you keep response packets routed to the right uart idk maybe vesc packets have some kind of request response identifiers. anyhow I get if you don’t want to give too much away. was just trying to think how things might break. thanks for that info. it makes sense.
Hi @Ricco I no want I am ending up bumping a old thread for a stupid reason but was wondering if this could be used instead of adding 2 devices to 1 vesc rather 1 uart device to 2 vesc6 in order that I don’t have to use canbus
Thanks a lot
Ricco has said before remotes shouldn’t be connected to the USplit, as consistent performance can’t be guaranteed
Just make a splitter for the remote, like people do with PPM. Imo doesn’t make sense to put the same splitter you could have had before… After additional electronics
In addition to what @Sn4Pz said, Depending on the device and the messages it is sending to the ESC, you may be able to connect the TX from the UART device to the RX of both ESCs. I have heard of this being done before.
So, one Firefly Nano UART based remote and a DAVEGA X is not recommended? Why exactly is that? My problem is that it’s a single drive…
Because the Uart will have to juggle packets between the remote and the davega, meaning the reciever could miss an important shift in throttle position.
Alternatively, if the Uart were to choke and somehow malfunction, your remote reciever won’t be able to communicate with the remote
Only remotes that are controlling the motor(s) over UART are not recommended with the uSplit. The Firefly Nano should provide the option between PPM+UART or UART only. In PPM+UART mode only the ESC’s stats are communicated over UART which is perfectly fine to use with the uSplit. In UART only mode the throttle would be controlled through UART messages and because of the reasons @Sn4Pz stated, this should not be used with the uSplit.
Ah ok. Just out of curiosity, does the uSplit dump any packets or is it able to process everything with two uart devices (and a master) connected?
With the most recent FW update, I have been seeing the the only packets getting dropped now are either due to noise in the UART RX/TX or a device requiring priority (ex. writing motor settings through metr). This is with 3 devices (DAVEga X, Metr Pro, TTL) and the ESC connected, using a baud of 115200
That looks good! Can we also check this ourselves? I know it’s not recommended but I really want to use the Firefly Nano remote with a Davega X. When so less packets are dropped (and I would be able to check it myself), I’d be pretty confident.
Anyone is welcome to perform their own analysis of the uSplit’s communication It just requires a uSplit, a logic analyzer, and some soldering experience. A bit of patience doesn’t hurt either. You need to use the logic analyzer to monitor the TX/RX signals of each port on the uSplit. To connect the logic analyzer to those pins I solder a wire to each to tap it out.
Ahh okay. Thought it was built in your software or something. You mean something like this? https://nl.banggood.com/USB-Logic-Analyzer-24M-8CH-Microcontroller-ARM-FPGA-Debug-Tool-p-1177821.html
Yup thats the exact kind I use
UPDATE:
I have 3 uSplits left to be sold. If you would like one, please DM me.
The price is $30 per uSplit + shipping, and paypal fees
When I plug my usplit and my metr.pro on together, it detects the metr but I am receiving no data, it shows 00 everywhere. Any fix?
Edit: fixed, plugged it in the wrong port
Another question, the device don’t read esc temp from both vescs? One of my ESC temp went to 0 after I connected everything.
Have you updated to the v0.7 uSplit FW? It should fix any issues you are having with a dual ESC setup.
Ah no, I didn’t, I’ll try that
I’ve updated the uSplit layout once more to make HW version v1.2. There were 3 changes made from v1.1 to v1.2:
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Added resetable fuses to the 3v3 and 5v lines that have a 500mA hold current and 1A tripping current. Thank you @Darkie02 for the suggestion.
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Increased the trace width of both 3v3 and 5v traces to decrease any effect the uSplit may have on power distribution to the connected devices
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Removed the series resistors from the rx/tx lines. Due to the way the VESC FW configures the UART pins, the series resistors just caused the communication to fail.
I ordered v1.2 PCBs a few weeks ago but due to Chinese New Years and the Coronavirus, the order has been delayed until Feb. 18th. Once the new HW is tested, I plan to order a large batch of assembled boards and sell them on my site.
Until then I can still build up uSplits by hand. Just PM me with your order request if you are interested. v1.1 HW is $30 each and v1.2 HW is $35 each.
Damn. I might have to upgrade for science?
I cannot DM yet, but I would like one!