Author Topic: Setting 1/8 vs 1/16 scan rate  (Read 137 times)

Online k6ccc

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Setting 1/8 vs 1/16 scan rate
« on: January 12, 2018, 10:17:39 AM »
Did some searching on the forum and the FPP manual and can't find the answer to this.
How do you tell FPP what scan rate to use for different Px panels?  Or does FPP detect the difference from the panel?
I currently have some P10 panels that are 1/8 scan, and considering purchasing some P5 panels that are 1/16 scan.  I have not found any way to tell the software what the correct scan rate to use.
I am using a Pi 3 with Pi Hat in bridge mode running FPP version 10. something (not in front of me right now) driven by LOR software.

Jim

Jim

Online k6ccc

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Re: Setting 1/8 vs 1/16 scan rate
« Reply #1 on: January 12, 2018, 11:12:01 AM »
Of course I meant FPP version 1.10.something - damn fat fingers...

Offline CaptainMurdoch

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Re: Setting 1/8 vs 1/16 scan rate
« Reply #2 on: January 12, 2018, 11:51:21 AM »
FPP on the Pi currently supports fewer configs that FPP on the BBB, but you can use 1/16 scan 32-row panels on the Pi.  If these are 64x32 panels, you will configure FPP as if it was two 32x32 panels.  Once we update to the newer version of the library we use, we should be able to support more options, but there will need to be a hardware change on the Hat to support any panels requiring the 'E' control line.
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Chris

Offline dkulp

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Re: Setting 1/8 vs 1/16 scan rate
« Reply #3 on: January 12, 2018, 12:34:09 PM »
FPP on the Pi currently supports fewer configs that FPP on the BBB, but you can use 1/16 scan 32-row panels on the Pi.  If these are 64x32 panels, you will configure FPP as if it was two 32x32 panels.  Once we update to the newer version of the library we use, we should be able to support more options, but there will need to be a hardware change on the Hat to support any panels requiring the 'E' control line.


The "E" control line is only needed for the 1/32 scan panels.   I don't recommend even bothering.   I was able to get them working on the BBB (custom board), but the refresh is SOO bad once you get above 2 per chain  and the panels are so tiny, it didn't make much sense to support.    The 1/16 scan just needs the A-D lines which I think the PiMatrix adapters use.   The 1/32 would have a scan rate of a bit less than 1/4 of the P10's of the same "pixel width".  Most 1/32 are 64pixels wide, so equivalent to 2 P10's.   Thus, the 11-12 output chain of P10's would be roughly equivalent two 2 of the 1/32 panels.  Since the 1/32 panels are about "P2" or "P3", they are very small.   A PiHat would be able to drive 6 of them, 9 at most.  That would be a very small matrix.  :)
Dan Kulp

Online k6ccc

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Re: Setting 1/8 vs 1/16 scan rate
« Reply #4 on: January 12, 2018, 01:12:00 PM »
Thanks for the detailed answers.  I had previously done enough reading to know most of what was said, but did not answer the original question - how do I tell FPP what scan rate to use (although I gathered I dont need to manually specify it).  For my application small is the plan.  The proposed panel will be within a few feet of people reading it (mostly text) so the close spacing is desired, and Im aiming for 3W x 2H so I could go with 3 outputs of 2 panels each so refresh rate should not be too much of a problem.



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Offline JonB256

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Re: Setting 1/8 vs 1/16 scan rate
« Reply #5 on: January 13, 2018, 08:23:08 AM »
... - how do I tell FPP what scan rate to use (although I gathered I dont need to manually specify it). 


Scan rates are shown in the drop down choices for panel sizes (WxH). Pick what matches or experiment if you don't see your exact match.

Online k6ccc

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Re: Setting 1/8 vs 1/16 scan rate
« Reply #6 on: January 13, 2018, 08:37:06 AM »
No.  Scan rate is not shown there - only panel size - at least on the firmware version Im using.



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Offline dkulp

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Re: Setting 1/8 vs 1/16 scan rate
« Reply #7 on: January 13, 2018, 09:14:06 AM »
No.  Scan rate is not shown there - only panel size - at least on the firmware version Im using.



Yea... The Pi is much more limited.   I think just selecting the 32x32 panel size will do it on the Pi.

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Re: Setting 1/8 vs 1/16 scan rate
« Reply #8 on: January 13, 2018, 11:58:01 AM »
Yea... The Pi is much more limited.   I think just selecting the 32x32 panel size will do it on the Pi.

I could not attach a screen capture, so here is a link to a screen capture...

http://www.newburghlights.org/images/FPP_no_scan_select.png

 

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