# No output on P7 marked as P6 for analog servo use **URL:** \ **Category:** OpenMV Boards\ **Created:** [March 1, 2022, 8:00pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887 "2022-03-01T20:00:07Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![kwagyeman](https://yyz1.discourse-cdn.com/flex029/user_avatar/forums.openmv.io/kwagyeman/32/4_2.png) [@kwagyeman](https://forums.openmv.io/u/kwagyeman)\ **Post date:** [March 11, 2022, 11:40pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/21 "2022-03-11T23:40:06Z")
850nm. Examples are in examples in the IDE. Please use the RPC library instead of anything else. ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 11, 2022, 11:56pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/22 "2022-03-11T23:56:04Z")
You mentioned that before about the Remote Procedure Call Libraries, I’m not sure I understand what they are in this context, and what needs to change for use. ---
**Author:** ![kwagyeman](https://yyz1.discourse-cdn.com/flex029/user_avatar/forums.openmv.io/kwagyeman/32/4_2.png) [@kwagyeman](https://forums.openmv.io/u/kwagyeman)\ **Post date:** [March 13, 2022, 5:52am UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/23 "2022-03-13T05:52:47Z")
You asked about the Arduino Master and Slave examples. We have some old stuff still in the example folder that I don’t recommend to use. ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 15, 2022, 4:23am UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/24 "2022-03-15T04:23:27Z")
Hi Kwagyeman; Well, finally had a chance to look up that RPC stuff. Looks interesting, but for my application I don’t have any Python Masters to use. Just ARD MEGA and RoboRIO running Java. Neither Java nor Python are friends of mine. So most of this code runs in the ARD. Except the little camera bit to do the image processing. Got a nice 3 way I2C running. Real problem is that the camera will just crash after a while with timed out frame capture. Will RPC get rid of that or do I still need the PLUS? Stimpy ---
**Author:** ![kwagyeman](https://yyz1.discourse-cdn.com/flex029/user_avatar/forums.openmv.io/kwagyeman/32/4_2.png) [@kwagyeman](https://forums.openmv.io/u/kwagyeman)\ **Post date:** [March 15, 2022, 12:56pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/25 "2022-03-15T12:56:50Z")
I don’t know why it’s crashing given a frame timeout. Do you have example code that shows the issue in the smallest amount of code? ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 18, 2022, 5:53pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/26 "2022-03-18T17:53:12Z")
Hi Kwagyman; Is there anything special about the MPJEG stream coming from the camera? I don’t seem to be able to pick it up automatically from my Roborio. Thanks, Stimpy ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 18, 2022, 10:31pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/27 "2022-03-18T22:31:01Z")
Hi Kwagyman; After looking into your forum, I see that this has been an ongoing problem for a while. No way to get a UVC stream along with running a script. Not very useful. Here’s what I’ve tried so far and where I could use a little guidance. I tried to load that UVC.bin to the H7 plus and I can indeed see that a USB camera is being noted by the Roborio. I see a USB camera 0 show up. But can’t seem to grab the image. This is being done by standard openCV video library calls. Is there any interface to the camera using openCV? I was thinking that linux supports openCV therefor I may have a chance to recover some functionality from the camera as a standard USB input. As I understand the camera falls back to just an image supplier once the UVC.bin firmware is loaded. If I would have known, I wouldn’t have bothered with it. Alternatively, if you can clue me into the correct openMV calls, I may be able to get it to run with a script in place provided that I can do that from that script in the camera. Any code suggestions at this point would help. Thanks, Stimpy ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 19, 2022, 2:17am UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/28 "2022-03-19T02:17:14Z")
Hi Kwagyman; I’ve seen the light on your idea to use the RPC connection. I have just one small problem. In order to transfer data from the cam’s USB connection to my hosting PC I need to traverse the network thru the Roborio. I looked into it and the 'rio has a port forward capability that seems like it could work to simply stream over the net to a screen. Would be a good solution. I’ve already downloaded the PY scripts for the cam and pc. Can you suggest how this could be set up? the port forward on the 'rio looks like this PortForwarder.add(8888, “wpilibpi.local”, 80); My reckoning is that the 2 port numbers will be tied thru the 'rio IVP4 address? So what could I do? Connect the Cam to it at that IP and one of the ports? then the other to the host script? Thanks, Stimpy ---
**Author:** ![kwagyeman](https://yyz1.discourse-cdn.com/flex029/user_avatar/forums.openmv.io/kwagyeman/32/4_2.png) [@kwagyeman](https://forums.openmv.io/u/kwagyeman)\ **Post date:** [March 19, 2022, 9:15pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/29 "2022-03-19T21:15:02Z")
Umm… The camera needs to be connected to the PC in this case directly. I don’t know about port forwarding. ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 24, 2022, 2:43am UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/30 "2022-03-24T02:43:02Z")
Having some problems with the RPC lib on the CAM. Won’t run. Sez it needs to import the serial lib, but not available? Where do you keep it? ---
**Author:** ![kwagyeman](https://yyz1.discourse-cdn.com/flex029/user_avatar/forums.openmv.io/kwagyeman/32/4_2.png) [@kwagyeman](https://forums.openmv.io/u/kwagyeman)\ **Post date:** [March 24, 2022, 5:18pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/31 "2022-03-24T17:18:09Z")
pip install pyserial ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 25, 2022, 6:25pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/32 "2022-03-25T18:25:59Z")
Hi Kwageyman; Sez already done and points to my Python 3.6 package folder? Stimpy ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 25, 2022, 6:34pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/33 "2022-03-25T18:34:55Z")
I guess I should have asked how to get an image of the lib on the camera drive? I tried simply using the pip command from the cam USB drive but nothing doing. Not that familiar on how to direct the install path for a lib? ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 25, 2022, 6:47pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/34 "2022-03-25T18:47:20Z")
Hi Kwagyman; Thought I would try adjusting the pip target, got this error set on the CMD line D:\>pip install --target=d: pyserial Collecting pyserial Using cached pyserial-3.5-py2.py3-none-any.whl (90 kB) Installing collected packages: pyserial Successfully installed pyserial-3.5 ERROR: Exception: Traceback (most recent call last): File “C:\Python310\lib\site-packages\pip\_internal\cli\base\_command.py”, line 173, in \_main status = self.run(options, args) File “C:\Python310\lib\site-packages\pip\_internal\cli\req\_command.py”, line 203, in wrapper return func(self, options, args) File “C:\Python310\lib\site-packages\pip\_internal\commands\install.py”, line 446, in run self.\_handle\_target\_dir( File “C:\Python310\lib\site-packages\pip\_internal\commands\install.py”, line 456, in \_handle\_target\_dir ensure\_dir(target\_dir) File “C:\Python310\lib\site-packages\pip\_internal\utils\misc.py”, line 110, in ensure\_dir os.makedirs(path) File “C:\Python310\lib\os.py”, line 225, in makedirs mkdir(name, mode) PermissionError: [WinError 5] Access is denied: ‘D:\’ Some sort of permission error? How to fix? Thanks, Stimp ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 25, 2022, 7:10pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/35 "2022-03-25T19:10:41Z")
OK, got a successful install on serial once I actually put the serial.gz file on the cam drive. Then running the pip install works. But… Now since the lib is not on the cam root path, the IDE doesn’t find it? I’ve been tinkering with the path, no luck. Clues? Stimp ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 25, 2022, 8:16pm UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/36 "2022-03-25T20:16:57Z")
The Documentation for using usys.path is very weak. I have tried using a line of code like this import usys pathlist = [“\dist\serial”] usys.path = pathlist import gc, serial, socket, struct, time Never finds the serial lib in the above dir off the cam’s root. The error is Traceback (most recent call last): File “”, line 9, in TypeError: ‘list’ object isn’t callable ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 26, 2022, 2:13am UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/37 "2022-03-26T02:13:58Z")
Hi Kwagyman; Here is code I think modifies the usys.path variable: systempath = usys.path print(systempath) systempath += [‘D:\dist\serial’] print(systempath) usys.path.append(systempath[0]) print(usys.path) Prints: [‘D:\dist\serial’] Which I think should find the lib directory as listed in the above path. Still cannot import serial. Not Found. Help. Thanks, Stimpy ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 26, 2022, 2:15am UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/38 "2022-03-26T02:15:11Z")
Had High hopes of using your RPC lib. Can’t work. ---
**Author:** ![kwagyeman](https://yyz1.discourse-cdn.com/flex029/user_avatar/forums.openmv.io/kwagyeman/32/4_2.png) [@kwagyeman](https://forums.openmv.io/u/kwagyeman)\ **Post date:** [March 26, 2022, 6:10am UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/39 "2022-03-26T06:10:09Z")
Dude, the camera doesn’t run desktop Python. The rpc lib for the camera is on it already in MicroPython. There’s an RPC lib for the desktop that you run to connect to the camera. See the documentation for the RPC library on the camera then our GitHub for the one on the PC. It is concerning that you are trying to make desktop Python work on the OpenMV camera and don’t seem to notice this. ---
**Author:** ![Stimpy](https://avatars.discourse-cdn.com/v4/letter/s/779978/32.png) [@Stimpy](https://forums.openmv.io/u/Stimpy)\ **Post date:** [March 27, 2022, 12:39am UTC](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887/40 "2022-03-27T00:39:19Z")
Hi Kwagyman; Not clear at all neither from your commentary nor you docs. Then how do I set up a server ? Stimpy [Previous page](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887.md?page=1) [Next page](https://forums.openmv.io/t/no-output-on-p7-marked-as-p6-for-analog-servo-use/6887.md?page=3)