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Asked — Edited

Usb To Serial Connection Camera Option

With the option to use the EZB in serial to USB you lose the option for the camera since the connections use the camera port. Is it possible to add another EZB like the IO Tiny to connect the camera too, then hard wire both EZBs together? I can't use Wi-Fi on either EZB.

There is a very specific reason I want to use the EZB camera and not a usb webcam, but i still need the EZB wired to the computer.


Edit: Please visit post #37 for the update on the usb/serial cable I used, new wiring diagram and notes

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Synthiam
#29  
Do not connect any RTS or CTS - it's not needed, as mentioned above. For safe measure, you could connect the camera's RTS line to GND.

Please connect TX to RX
Please connect RX to TX

I would recommend trying your camera with the ez-b to ensure it still works after providing it 5v. It may be damaged.

Next, you can specify the baud rate of 3,333,333 in the Serial Terminal (PC) to verify that data is indeed being transmitted to the computer over the USB UART cable.
#30  
OK so tx to rx and rx to tx are connected correctly, no RTC or CTS connected.
Terminal shows a connection at 3,333,333. I changed computers and cameras to make sure com ports working and camera working. I'm now on com 3:

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On New computer and camera I get this error:

Camera Initialized: COM3 @ 320x240
UART Camera Error: System.UnauthorizedAccessException: Access to the port 'com3' is denied.
at System.IO.Ports.InternalResources.WinIOError(Int32 errorCode, String str)
at System.IO.Ports.SerialStream..ctor(String portName, Int32 baudRate, Parity parity, Int32 dataBits, StopBits stopBits, Int32 readTimeout, Int32 writeTimeout, Handshake handshake, Boolean dtrEnable, Boolean rtsEnable, Boolean discardNull, Byte parityReplace)
at System.IO.Ports.SerialPort.Open()
at EZ_B.UARTVideo.MjorDt1ipt(Int32 , Object )
Camera Disabled
Synthiam
#31  
Denied because you're still connected to the camera using the terminal program. You can only access a COM port with one program at a time.
#32  
.....well never trust a cable guide from china. The online image of the PL2023 wiring is incorrect. The TX and RX are mismarked. At the last minute I decided to try changing the TX and RX wires and Bingo I have a steady and fast frame rate!

Thank you for hanging in there with me.
#33  
I will re edit all the correct wiring and repost so anyone else who wants to convert their ez camera to USB will have a correct wiring diagram if they use the PL2023.
Synthiam
#34  
Nice - glad it's working. I bet it works real fast and responsive too! The camera connected directly to the PC would be amazing fast
#36  
Here is the wiring diagram when using the PL2303 to convert the ez camera to a usb camera. The PL2303 has baud rates up to 12mbps, so it supports 3,333,333 baud for the ez camera. It’s $10 and works great!

Please not DO NOT cross the TX and the RX, the wiring diagram from China is incorrect. Please connect TX to TX and RX to RX.

Do not use the 5 volts from the cable but rather connect 3.3v and ground from the EZB using the regulated 3.3v on the Analog ports. also connect a ground from the EZB to RTC.

Link to PL2303HXD from amazon: PL2303HXD

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#37  
Hey guys I’m adding the camera to Alena. When connected to ARC and activated on the com port, I keep getting glitches in the image about every 30 to 40 secs. ( see below) Any idea what could be causing? I checked wiring and swapped out cameras and exhibits same behavior.


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Synthiam
#38  
Either the rts and CTs are not connected correctly or the data wires are noisy
#39  
Ok I didn’t connect at all because of the quote from #24. Maybe I misunderstood.

Quote:

You don't need cts or rts actually. I realized there's enough buffer on the pc


Maybe not enough buffer after all?!?
Synthiam
#40  
Oh right! Yes that’s right. I forgot, you don’t need CTs rts. The buffer is huge. Really huge.

So I’m guessing it’s noise on the signal line
#41  
The lines are running across the top of a servo. Do you think that’s where the noise could be coming from? If so how can I shield the wires?
#44  
Ok still working through this issue. I built another one of these and have the same issue. I’ve tried twisting pairs I’ve tried ferrite rings and even aluminum foil! Lol.

I finally tried going back to the old ez double board cameras and I get less full frame glitches. But still glitchy.

Finally I noticed the pop up from below as I had not checked always show and here are constant error messages I am getting.


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#45  
This could be latency and or interference issue with the UART because I had similar issue with a questionable UART with my Omron camera (I do realize it is not 100% the same, but the challenges are similar), but mine actually blacked out the image every couple of seconds. My problems went away with a new UART because my was cheap to begin with.

I believe yours is a little higher end so I assume it's probably good. You followed DJ's suggestions which were good ones to rule out the most common hardware interference.

Aiming for less common now, I'd probably want to check the solder joints of the UART cable to the camera and maybe try a different cable or different wires to rule out a bad wire/connections.

Software side what helped my Omron UART latency also was a tip (Omron) had for going into the Windows Device Manager for the virtual COM port of the UART and then Advanced settings and then under Latency Timer, setting the value to less than 16 because it might improve performance. But adjusting it lower is an incremental playing game, because going too low can disrupt other things. Think of it like tuning in an old radio station, starting at 16, then 15, then 14, etc to see if the interference goes away.
Synthiam
#46  
Oh I never thought of that. The usb to uart adapter might be dropping packets. That’s a smart observation, and the most probable cause.
#47  
Geesh I’m away for a day and came back to all these great forum reply’s and interesting posts. I will give that a try in the morning. Thanks!
#48  
...i'll add since this came up in the feed..my issue was with my USB ports on both my laptops. I purchased a new computer and the issue went away completely for both my robots. Both those laptops were old.