Odd behaviour when using luma.ledmatrix on Unicorn 8x8 HAT
Closed this issue · 8 comments
Description
The following code works, but get sporadic behaviour - most commonly missed pixels:
import time
from luma.led_matrix.device import neopixel, UNICORN_HAT
from luma.core.render import canvas
device = neopixel(width=8, height=8, mapping=UNICORN_HAT)
for y in range(device.height):
for x in range(device.width):
with canvas(device) as draw:
draw.point((x, y), fill="green")
time.sleep(0.5)Any observations and patterns
On launch, the entire HAT will light up briefly. Sometimes it's white/bright colours, sometimes it's a random selection of colours. Green dot begins moving across the display, but after a short while - usually by line #3 or #4 it will start 'jumping' (missing pixels).
Your device type (PiZero / 2B / 3B, etc)
Pi 3B (less than a week old), no mods other than the HAT itself.
OS and kernel version (paste output of uname -a)
Linux ninja 4.4.38-v7+ #938 SMP Thu Dec 15 15:22:21 GMT 2016 armv7l GNU/Linux
$ cat /etc/*-release
PRETTY_NAME="Raspbian GNU/Linux 8 (jessie)"
NAME="Raspbian GNU/Linux"
VERSION_ID="8"
VERSION="8 (jessie)"
ID=raspbian
ID_LIKE=debian
HOME_URL="http://www.raspbian.org/"
SUPPORT_URL="http://www.raspbian.org/RaspbianForums"
BUG_REPORT_URL="http://www.raspbian.org/RaspbianBugs"
No mods other than enabled SPI, disabled boot to Desktop Manager and enabled SSH
Output of dmesg after running the demos
Do you want entire output? Ok to paste in comments?
What amp rating does the power supply provide?
2.5A (https://www.amazon.co.uk/gp/product/B01M03T0UB/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1)
What other peripherals are connected? screen, keyboard, mouse, WIFI, etc?
None - just power and the HAT. Wifi is built-in on Pi 3. Pi is accessed via SSH.
Do you get the same erratic behaviour if you use the official Pimoroni drivers?
No, these work consistently fine.
On the 8x4 Unicorn pHAT, I had to solder the header on - is this the same for the 8x8 HAT? - if so check for any bad solder joints
No, arrived complete and good to go.
@fullphat: could you post the contents of /boot/config.txt please?
This issue seems relevant/related: jgarff/rpi_ws281x#103
Also to note, I arbitrarily picked the ws2812 library to do the low level bit-banging. I will create a branch and use the 'other' library (rpi_ws281x) to see if we get consistent results.
@fullphat can you post a video?
@fullphat - there is a branch rpi_ws281x with a different low-level neopixel interface implementation, which works on my 8x4 pHAT, but fails miserably on Travis CI (it wonit build/install rpi-ws281x, see https://travis-ci.org/rm-hull/luma.led_matrix/jobs/197477506)
Curious to see if this fixes the issues you describe..
Gents - apologies - been maxed out with work. Give me a few days and I'll do some videos and try out the branched library.
@fullphat - any chance you could try the rpi_ws281x branch on your 8x8 unicorn hat?
@fullphat any news?
sorrysorrysorrysorry - will try to get to this ASAP!
Apologies all - I've since purchased the HD Hat and have been using the Pimoroni/PIL libraries to run it. Will try to get back to testing this but I'm rammed right now.