I am using openmv cam H7 plus with attached lcd shield which says “LCD shield rev.2”. About a year ago I had this setup run fine when testing with default example and some drawing.
Yesterday after a long break I updated IDE and firmware. That is when strange things started to happen.
Opening the lcd example yesterday did not work -at all- because for some reason open mv wanted to add some display.py script to the file sytem which seemed to use touch function and failed with some import gt911 or so…
Today I installed the latest develop firmware using extra/install latest firmware. Although it says it might be unstable I can now run the builtin lcd example without messing things up with this display.py script like yesterday.
However colors are broken. It looks as if color depth or Pixel format are broken.
Are any known issues with lcd shield support? I mean if the builtin examples won’t work, what else to trust.
Second part of my question is: check lcd — lcd driver — MicroPython 1.20 documentation
i noticed that in the example (see code below) we see import display. import lcd is not even possible with this firmware. But when ich hover over lcd in the line lcd = display.SPIDisplay() # Initialize the lcd screen.
help shows me code from an (old?) example which corresponds to the information given in th micropython docs.
So what is going on there? Is it some inconsistency in the firmware? What is the difference between import display in the latest example and import lcd from the wiki and many older examples? At the moment I feel lost.
fyi the code that shows after opening the example is as following
# LCD Example
#
# Note: To run this example you will need a LCD Shield for your OpenMV Cam.
#
# The LCD Shield allows you to view your OpenMV Cam's frame buffer on the go.
import sensor
import display
sensor.reset() # Initialize the camera sensor.
sensor.set_pixformat(sensor.RGB565) # or sensor.GRAYSCALE
sensor.set_framesize(sensor.QQVGA2) # Special 128x160 framesize for LCD Shield.
lcd = display.SPIDisplay() # Initialize the lcd screen.
while True:
lcd.write(sensor.snapshot()) # Take a picture and display the image.
edit:
I had access to an other computer with IDE 4.03 ( I not update as suggested of course). After downgrading the firmware to 4.4.3 I tried the example for the shield and with IDE 4.03 I have lcd imported in the example.
Just as described in the micropython api and sample sources. In that configuration I cannot (as expected import display).
Everything works, colors are ok.
Attached you see a picture of my lcd shield plus the result running the current demo.
Given that using old firmware the results were ok so far, see above post, a hardware defect or generel incompatability seems unlikely to me.
I have tried lcd.init( bgr=True|False, swap_bytes=True|False) in all combinations.
Will try that later.
I was used to have the display work out of the box with older firmware. After updating and using the display class from the latest firmware the problems showed up. Former firmware using lcd class did indeed work out of the box as you expected.
You’re right I just tested it, and it is broken indeed, but it’s not related to byte_swap/BGR, seems to be an issue with the buffering. If you pass triple_buffer=False for now it will look normal. We’ll fix this and it will work with the defaults with no special args. Note you should still use the latest firmware and latest scripts.
