#interesting. that is rotated by 180

1 messages · Page 1 of 1 (latest)

dreamy fable
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OK maybe that is what is throwing me off. If Pin 1 is at the top left on the notched side (R1) then is Pin 2 B1 or does it have odd pins on the left and even pins on the right? If the latter, then Address Line E would be the 4th pin down on the right, like this? That does make Address Line E Pin 8.

HUB75_Pinout_Rev_1.jpg
proven wing
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(ignore the sizes mentioned in the URL)

prisma mesa
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yes, for this type of rectangular connector, odd pins are in one column, and even pins in the other

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it will make more sense if you have a matching uncrimped ribbon cable connector to look at

dreamy fable
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Thanks. I learned the hard way that some LED panels that are 64x64 and larger only have 2 or 3 address lines and use LED driver chips (ex FM6124, ICN2038S) that use a shift register to control the row address. I can’t control these panels with a Matrix Portal S3. I bought several P2 128x64 panels that have 5 address lines and connected them to my Matrix Portal S3 but so far I can’t get them to do anything – not even a flash when I power up.

I think (hope) it is just an address line issue which is why I am looking for info about address line E. The Matrix Portal S3 connects address line E to Pin 8 by default. The HUB75 pinout printed on these panels shows address line E is the 4th pin down on the right side, so I think it should work but it doesn’t. Am I missing something?

manic pine
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I doubt that's the only problem: a missing address line will give some display, but misaligned in some way. Having nothing at all points to a more basic problem. I'd look at power and clock first.

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Also latch and enable

dreamy fable
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Yeah it is concerning, especially since I bought 4 of them. After getting 2 panels that only had 3 address lines, the dreaded ICND2083S LED driver chip, and only HUB75 in, I contacted 20 LED vendors on Ali Express looking for P2 128x64 panels with 5 address lines and HUB75 in and out connectors. Only 2 had them so I went for it. I have been swapping back and forth between these panels, an Ali Express P4 64x32 panel and an Adafruit P2.5 64x32 panel. Those work fine so I know it’s not a problem with the Matrix Portal, power, or ribbon cable.

The HUB75 pinout is printed on the panels next to the HUB75 input connector and exactly matches the pic I posted earlier, so Address Line E is Pin-8 based on the pin numbering you provided. The working panels usually have some or all LEDs flash or do something when powering up. These 4 panels do NOTHING. It’s possible they sold me 4 dead panels but I have not given up yet. I don’t have an O-Scope so I don’t know how I could check CLK and LAT. The panels are made by MOEN. Here is a pic of the back.

P2_128x64_Panel_Back.jpg
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The pic of the HUB75 with the red arrows is from the Vendor. The arrows over the pins dont point to the right pins. I think they were just indicating that yes these panels have address lines A through E/

manic pine
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Electrically the panels are fairly simple, you could use a simple continuity tester to buzz out where the pins go.

dreamy fable
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Hmmm. I have a Fluke VTVM, so maybe I could trace the HUB75 pins but since I don't know where they are supposed to go I am not sure what I will gain from this. I have asked the seller to please send whatever documentation they have, if they have any. They have been quite supportive so there's hope. Thanks for all your help.

manic pine
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I figured that since you knew of the different chips in use, you had seen the schematics.