# Rpi4 + Adafruit hat + 32x32 adafruit panel

**URL:** <https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20>\
**Category:** Uncategorized\
**Created:** [November 13, 2020, 9:17pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20 "2020-11-13T21:17:09Z")\
**Posts on this page:** 10\
**Page:** 1

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**Author:** ![KrisRevi](https://avatars.discourse-cdn.com/v4/letter/k/a183cd/32.png) [@KrisRevi](https://rpi-rgb-led-matrix.discourse.group/u/KrisRevi)\
**Post date:** [November 13, 2020, 9:17pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/1 "2020-11-13T21:17:09Z")

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so im running **Rpi4 + Adafruit hat + 32x32 adafruit panel** and every 2 lines are black/off…

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**Author:** ![marcmerlin](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/marcmerlin/32/40_2.png) [@marcmerlin](https://rpi-rgb-led-matrix.discourse.group/u/marcmerlin)\
**Post date:** [November 14, 2020, 1:54pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/2 "2020-11-14T13:54:55Z")

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Sounds like an addressing problem. Is it an abcd panel?  
What command line did you use to run it?

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**Author:** ![KrisRevi](https://avatars.discourse-cdn.com/v4/letter/k/a183cd/32.png) [@KrisRevi](https://rpi-rgb-led-matrix.discourse.group/u/KrisRevi)\
**Post date:** [November 14, 2020, 2:39pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/3 "2020-11-14T14:39:02Z")

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so im using

_sudo ./demo -D0 --led-gpio-mapping=adafruit-hat-pwm --led-slowdown-gpio=2_

Running this panel : [https://www.adafruit.com/product/1484](https://www.adafruit.com/product/1484)

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**Author:** ![marcmerlin](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/marcmerlin/32/40_2.png) [@marcmerlin](https://rpi-rgb-led-matrix.discourse.group/u/marcmerlin)\
**Post date:** [November 16, 2020, 2:59pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/4 "2020-11-16T14:59:25Z")

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I assume you are using the adafruit hat?  
Did you look at all the addressing options in the main README on github?

```auto
have 4 address line (A, B, C, D). For such matrices is necessary to
use `--led-row-addr-type=2` parameter. Also the matrix Qiangli Q10(1/4)
have "Z"-stripe pixel mapping and in this case, you'd use two parameters
at the same time `--led-row-addr-type=2 --led-multiplexing=4`.

```

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**Author:** ![KrisRevi](https://avatars.discourse-cdn.com/v4/letter/k/a183cd/32.png) [@KrisRevi](https://rpi-rgb-led-matrix.discourse.group/u/KrisRevi)\
**Post date:** [November 18, 2020, 10:26pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/5 "2020-11-18T22:26:33Z")

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just tried it and it got worse 😕

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**Author:** ![marcmerlin](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/marcmerlin/32/40_2.png) [@marcmerlin](https://rpi-rgb-led-matrix.discourse.group/u/marcmerlin)\
**Post date:** [November 19, 2020, 2:28am UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/6 "2020-11-19T02:28:34Z")

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I’m not sure what mapping is best for 32x32, you can try looking in the github bugs if you find someone else and maybe find an answer there.  
@hzeller is currently travelling and probably unlikely to be able to help right now.

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**Author:** ![KrisRevi](https://avatars.discourse-cdn.com/v4/letter/k/a183cd/32.png) [@KrisRevi](https://rpi-rgb-led-matrix.discourse.group/u/KrisRevi)\
**Post date:** [December 18, 2020, 12:54pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/7 "2020-12-18T12:54:58Z")

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is @hzeller back from travelling or?

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**Author:** ![marcmerlin](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/marcmerlin/32/40_2.png) [@marcmerlin](https://rpi-rgb-led-matrix.discourse.group/u/marcmerlin)\
**Post date:** [December 18, 2020, 2:51pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/8 "2020-12-18T14:51:11Z")

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I have no idea, but you can try to do a bit of research too 🙂

1. they are from adafruit, and they work with their lib on arduino, so it can’t be a crazy addressing
2. [https://cdn-shop.adafruit.com/1200x900/1484-05.jpg](https://cdn-shop.adafruit.com/1200x900/1484-05.jpg) does not show ABCD on the connector, but it shows they are 16S, So, one line displayed out of 16, which means they are ABCD

ABCD means that the connector can feed 32 lines (R1 goes to lines 1-16, and R2 goes to lines 17 to 32).

sudo ./demo -D0 --led-gpio-mapping=adafruit-hat-pwm --led-slowdown-gpio=2 does not tell the lib how big your panel is.

You’d want something like demo -D0 --led-gpio-mapping=adafruit-hat-pwm --led-slowdown-gpio=2 --led-rows=32 --led-cols=32 --led-chain=1

Did you at least tell the library how big your panels were?

Another option is that they could be 2x 32x16 panels chained together, and would be  
demo -D0 --led-gpio-mapping=adafruit-hat-pwm --led-slowdown-gpio=2 --led-rows=16 --led-cols=32 --led-chain=2  
but from the markings in the back, I doubt it.

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<div class="post-metadata">

**Author:** ![KrisRevi](https://avatars.discourse-cdn.com/v4/letter/k/a183cd/32.png) [@KrisRevi](https://rpi-rgb-led-matrix.discourse.group/u/KrisRevi)\
**Post date:** [December 18, 2020, 2:53pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/9 "2020-12-18T14:53:05Z")

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i’ve done everything and googled EVERYTHING! that is why im reaching out to the author of the lib!

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**Author:** ![marcmerlin](https://yyz2.discourse-cdn.com/free1/user_avatar/rpi-rgb-led-matrix.discourse.group/marcmerlin/32/40_2.png) [@marcmerlin](https://rpi-rgb-led-matrix.discourse.group/u/marcmerlin)\
**Post date:** [December 18, 2020, 2:57pm UTC](https://rpi-rgb-led-matrix.discourse.group/t/rpi4-adafruit-hat-32x32-adafruit-panel/20/10 "2020-12-18T14:57:05Z")

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Kris, if I may, please read [http://www.catb.org/~esr/faqs/smart-questions.htm](http://www.catb.org/~esr/faqs/smart-questions.htm)  
You only posted “it doesn’t work” and you expect others to magically know how to help. There are so many panels that are all wired in different and sometimes weird ways.  
You didn’t post a copy of your panel’s back, with markings on ABC vs ABCD or scan lines (S8 S16 S32), those matter.  
You never posted the full list of arguments you gave to demo. The example you gave, does not list the panel size.  
I gave you 2 ways to run with the correct size for your panel, you did not confirm that you tried them, how they failed, and did not give a picture of the output for each of the 2 options I gave you.

Henner is not going to be able to help any more than anyone else in those conditions 🙂
