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zappanaut / usb-atx-ctrl

Using RP2040-Zero to control ATX operations via USB.
MIT License
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A few simple questions about building these #2

Open mortenboldt opened 1 year ago

mortenboldt commented 1 year ago

Hi Thank you for making this available. I've ordered 5 boards from JLCPCB and it came to $10.99 including shipping to Denmark. I'm a software guy and I've never attempted to build anything like this, so I have a fun challenge ahead of my trying to solder the parts and get everything working.

A couple of questions

  1. Am I right in assuming that I can just hook up pretty much any number of these through a USB hub?

  2. In this picture you've got a 3.3v and a ground hooked up to J2. Where are you pulling those from?

  3. In the picture it looks like a bracket from a network card. Do you know which card it came from, since it looks like the holes line up?

  4. Any recommendation for a cheap place to buy the parts from the BOM?

Thank you Morten

zappanaut commented 1 year ago

Hello Morten, I am also only a hobbyist EE ;) Regarding soldering it is important that you use proper flux and solder. Especially if you want to go lead-free you need additional flux - sometimes quite a lot of it. I am sure there are plenty of tutorials on YT though. I also chose quite "big" SMT parts for hand soldering. Maybe next time I will try the assembly service for these parts, too.

Regarding your Questions:

  1. Am I right in assuming that I can just hook up pretty much any number of these through a USB hub?

I don't see any limitations, but have to admit that I am using only two right now. In fact it was the main reason for me to build this, to monitor and control all PCs simultaneously.

  1. In this picture you've got a 3.3v and a ground hooked up to J2. Where are you pulling those from?

These are only for powering another test board. You can safely ignore them.

  1. In the picture it looks like a bracket from a network card. Do you know which card it came from, since it looks like the holes line up?

It is from an old PCI Ethernet card Intel Pro/100 that was collecting dust here for decades. But it also needed some metal rework. I think the distance of the screw holes (ca. 42mm) are quite common, though.

  1. Any recommendation for a cheap place to buy the parts from the BOM?

Since you are located in Denmark, I went with these PhotoMOS SSR from ebay. There are no special requirements regarding the other parts. You can find them even on amazon. The IDC type pin header might be a bit more difficult to source, but you can also go with the simple ones. Oh, and don't buy the RP2040-Zero boards with pre-soldered pin headers! Otherwise you will have to remove the ones at the short end (sorry, there are all the vias in place :man_facepalming:).

These are distributors that come to mind, that are a bit less expensive (in no particular order):

Hope that gives you a good starting point and that you will enjoy this challenge! :)

Regards Peter

mortenboldt commented 1 year ago

Hello Peter,

Thank you very much for the answers. I'm going to order the parts today and hopefully I will be controlling 4 machines in the not too distant future.

I'll post a message in here once I have it running.

Kind regards, Morten

zappanaut commented 1 year ago

@mortenboldt if you are still looking for brackets you may want to have a look at this offer: https://www.ebay.de/itm/274598193347

mortenboldt commented 1 year ago

@mortenboldt if you are still looking for brackets you may want to have a look at this offer: https://www.ebay.de/itm/274598193347

Thanks you very much. I am having a friend 3D print some brackets, so I hope that will work. The PCBs are on their way in the mail and I've ordered the components from the BOM.

hiarcy commented 1 year ago

@zappanaut Hello, I'll be piggybacking a bit on this since I have questions along similar topic. These are definitely going to be beginner-ish questions as EE feels like rocket science to me.

Am I correct in understanding that you use a single board per client (i.e. PC with ATX pins), which then gets connected to a USB slot on the client itself or does it have to go straight to the HDMI switch?

I've yet to deal with anything custom boards so I'll be looking into KiCAD and how to get my own boards next. If I were to get them made, would I pass the supplier the entire KiCAD folder gerber zip?

In the BOM, I believe K1/2 are relays and I see on the schematics R1-R4 are attached to them (not sure if this is the correct terminology). Does this mean that between the relay and the ATX connector I need to solder a resistor on the back? Assuming this since I don't see it on the pictures showing the top of the board. Edit: Found the bottom side of the board, I believe this is correct.

Hopefully these questions makes sense, if not I will definitely try my best to further explain.

zappanaut commented 1 year ago

@hiarcy, very sorry for being late with my reply!

Am I correct in understanding that you use a single board per client (i.e. PC with ATX pins), which then gets connected to a USB slot on the client itself or does it have to go straight to the HDMI switch?

Yes, one board per connected computer. The USB connection goes directly to the PiKVM, so that you can control and monitor each computer independently from the KVM/HDMI switch.

I've yet to deal with anything custom boards so I'll be looking into KiCAD and how to get my own boards next. If I were to get them made, would I pass the supplier the ~entire KiCAD folder~ gerber zip?

Usually you upload the gerber.zip zu e.g. JLCPCB and check the preview then to see if everything looks fine. I ordered from JLCPCB without any problems.

In the BOM, I believe K1/2 are relays and I see on the schematics R1-R4 are attached to them (not sure if this is the correct terminology). Does this mean that between the relay and the ATX connector I need to solder a resistor on the back? Assuming this since I don't see it on the pictures showing the top of the board. Edit: Found the bottom side of the board, I believe this is correct.

Yes, K1/2 are PhotoMOS solid state relays. The resistors are limiting the current through the IR-LEDs inside the solid state relay and are placed on the backside of the PCB, as you already figured out.

Hope I could still help a bit and feel free to ask if more questions arise.

hiarcy commented 1 year ago

@zappanaut Perfect! Absolutely no worries, my parts should be coming in this week/early next week so I'll be able to mess around soon! I tend to learn better with on-hands experience. Will definitely reach out if I have any additional questions, thanks!

tiiilerteee commented 10 months ago

@zappanaut Hey, there! I know this hasn't had any activity for a few months, but I discovered the PiKVM a while back and was very excited to find something so great and less expensive than the commercial options; my only issue was controlling the power of multiple machines; and you have solved that! Very cool! Thank you. I am going to have 4 of your boards printed up from JLCPCB and try to get this project working. I currently only need KVM and ATX power control for two machines, but I would like to have a few extra boards in the event I want to expand later. Since it seems like you probably have been running this for a while, is there anything I should know before beginning? Any new pros or cons you have noticed since August? Thanks!

Two quick questions about where things plug in:

  1. I think you answered @hiarcy 's question well but I wanted to clarify. Attached is a PDF of how I believe everything should be plugged in; can you confirm? PiKVM-Illustration.pdf

  2. I see on usb-atx-ctrl-picture1.jpg that you have a black and white pair to +3.3v and GND (if I'm reading the schematic right). Is that to power the RPi-2040Z? If, so where does that power come from, or where does that black-and-white pair head to?

    Thanks so much!

Edit: I just caught the end of the thread of your convo with Johann. In my illustration I was planning on making some y cables with DuPont connectors but I'll go with your method of an 8pin IDC ribbon cable and crimp on an 8pin male connector near the motherboard side to run in parallel with the front panel connections.

tiiilerteee commented 9 months ago

FYI I wanted a back plate that fit a USB-C perfectly, after searching everywhere I finally found this: https://a.co/d/5WCrTXV

I'm going to buy a few and remove the board that comes with it and measure to make sure the ATX-CTRL will fit, if not I'll adjust the board mount points before I have them printed. I'll report back what I find.

zappanaut commented 8 months ago

Hello @tiiilerteee! I am very sorry for the huge delay!

@zappanaut Hey, there! I know this hasn't had any activity for a few months, but I discovered the PiKVM a while back and was very excited to find something so great and less expensive than the commercial options; my only issue was controlling the power of multiple machines; and you have solved that! Very cool! Thank you. I am going to have 4 of your boards printed up from JLCPCB and try to get this project working. I currently only need KVM and ATX power control for two machines, but I would like to have a few extra boards in the event I want to expand later. Since it seems like you probably have been running this for a while, is there anything I should know before beginning? Any new pros or cons you have noticed since August? Thanks!

I have two boards running for some time and did not notice any bigger problems. For me the most annoying is described here: https://github.com/pikvm/pikvm/issues/946 Another thing is, that you may have to use smaller resistors to drive the relay diodes as described here: https://github.com/zappanaut/usb-atx-ctrl/issues/3

Two quick questions about where things plug in:

1. I think you answered @hiarcy 's question well but I wanted to clarify. Attached is a PDF of how I believe everything should be plugged in; can you confirm?
   [PiKVM-Illustration.pdf](https://github.com/zappanaut/usb-atx-ctrl/files/13756811/PiKVM-Illustration.pdf)

Your illustration shows exactly how the board should be connected! :)

2. I see on usb-atx-ctrl-picture1.jpg that you have a black and white pair to +3.3v and GND (if I'm reading the schematic right). Is that to power the RPi-2040Z? If, so where does that power come from, or where does that black-and-white pair head to?

Unfortunately this picture caused some confusion before. The black and white cable was attached only for debugging purpose, so there should be no need to connect these. The board is actually powered from the USB port.

Thanks so much!

Edit: I just caught the end of the thread of your convo with Johann. In my illustration I was planning on making some y cables with DuPont connectors but I'll go with your method of an 8pin IDC ribbon cable and crimp on an 8pin male connector near the motherboard side to run in parallel with the front panel connections.

Let me know if you have more questions. I will do my best to respond more quickly then.