So I just got my new Khadas VIM in the post and am now reviewing docs.khadas.com and sadly do not have a clue where to start to get my Khadas VIM booting into Ubunutu for my plans to use it as a headless web server.
I have previously gotten a Raspberry Pi booting and work with Linux in VMs regularly for the past year so am not an SBC newbie, but I honestly can’t figure out where to start to get the VIM working? Is there a step-by-step tutorial anywhere to show how to get a new VIM booting into Ubunutu, that includes all the steps?
Thank in advance.
P.S. I use a 3 year old MacBook Pro so I do not have native USB C on my machine. Does USB 2.0 have enough juice to power my Mac? If not, where can I find a power supply for the weird 4 pin power connector?
Yes, I saw that link before. All it says is “VIN Port spec as a 4-Pin 1.25mm port.” When I google “VIN Port 4-Pin 1.25mm port” I get nothing useful. If I just google “VIN port” I get this: https://www.vinport.com
I would like a link to a power supply that I can purchase that would be compatible with the Khadas VIM.
It´s a JST connector 4pin 1.25mm (female)
you can find it on ebay
Thanks.
I can find the connectors on eBay, but cannot seem to find any power supplies for sale that use those connectors.
I am evaluating Khada VIM as the basis for a product we could use as a base for a product where we would just need to add software so I need to be able to find power supplies we can purchase to be able to include with the Khadas VIM.
I have many 5vdc 2 amp and 3 amp AC adapters with barrel connectors, so I made a crude Female USB-to-Female barrel adapter. This type of adapters are on ebay and elsewhere(?). An example, though I would check for correct polarity before using these.
I am hoping not to have to resort to deliver a jangle of adapters with our product.
If Khadas VIM has a connector for power, it seems absolutely crazy that there would be no power supplies to use with it. Or is my thinking somehow wrong here?
USB-C is main power supply for VIM, what you needed is just a USB adapter for the USB-C cable
VIN is extra power supply
USB host is also a optional extra power input
My concern is my use case would need the OTG USB port connected to my customer’s computer, and most of those are going to be USB 2.0 (0.5A) for the near future. So I assume that will mean I must provide my users with a wall wart power adapter using your VIN extra power supply or your USB host optional extral power input. Yet I cannot find a wall wart with support for a VIN or for USB A cable.
I continued looking and found these. Would you agree these would work as a power supply can cable I could package with a Khadas VIM to allow the USB OTG port to be available for the computer’s use?
I don’t doubt you, I had to use a few search terms before they popped up.
It is important to note that the two USB ports have different mA ratings.
The USB port next to the USB-C port(the same end as the switches) has a 900mA max.
The USB port next to the LAN port is rated at 500mA max.
In either case, these are substantially less than the 2+ Amps available through the USB-C or Vin header.
This could be a factor if you plan on using the remaining USB port for accessories.
I am aware that accessories connected to a USB A port can only draw 500mA, and that USB C can only draw 900mA max. However I am not skilled enough to read and understand the schematics which is partly why I have been pushing for off-the-shelf solutions.
Are you saying that if I connect a USB-C to a 5V2A power supply that it will not be able to provide 2A to the Khadas VIM? And that the same would be true if I were to connect power via VIN?
What about via the USB-A port? Can it draw 2A from a 5V2A power supply like the one I linked from Monoprice?
My use-case is as a headless server. I need one USB-OTG port to connect to my user’s laptop or desktop – and I expect to use the USB-C port for that – but I do not need the other two (2) USB-A ports so it one of them can support the full 2A of power then I believe the above links give me what I need (no?)
Thanks for asking that. The link provided has cables from 1.5ft all the way up to 15ft. We are considering offering our customers a choice of length (1.5ft vs. 3.0ft vs. 6.0ft) when we are in our “working prototype” phase and that will help us understand what most people would prefer, and if it makes sense to provide an option once we are in full production sales mode.
That said, we’d have to test the 6.0ft to see if it could provide enough power.
P.S. I usually want shorter cables and am always annoyed when I am supplied a 3ft cable for a 1.5ft need! FWIW.
The USB ports are protected by fuses. You will note from the schematic, the fuses are 500mA and 900mA. Current traveling in or out of the USB ports must travel through these fuses. Current in excess of 500mA or 900mA will blow the fuses, respectively.
That being said, running headless and not using USB devices will reduce current demand of the Vim. What the Vim needs for operation, is yet unknown to me. I have to assume, as Gouwa suggested the 900mA USB port as an alternate power input, it can be adequate to run the Vim. But if it is adequate, you could only utilize about 1Amp(1000mA) of the 2A adapter in your link(when powering via USB). The 2+ Amps supplied to the Vim through the USB-C or the Vin header is in excess of the current needed to run the Vim, the excess is provided to supply connected USB accessories power and/or the GPIO. So we know 2A is not required to run the Vim.
The USB-C port is good for 2A.[quote=“RDFTKV, post:17, topic:146”]
… 2+ Amps available through the USB-C or Vin header.
[/quote]
Yes, I don’t care for “too long for their purpose” cables either. However, better too long than too short.
