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DLPDLCR2000EVM: Resolution problem settings with i2c and raspberry pi

Part Number: DLPDLCR2000EVM
Other Parts Discussed in Thread: DLPC2607, DLP2000

Hello, I'm trying to setup dlp200evm with raspberry pi 4 b+. the issue I get is:

pi@raspberrypi:~ $ i2cdetect -y 2
0 1 2 3 4 5 6 7 8 9 a b c d e f
00: -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- -- -- -- 1b -- -- -- --
20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: -- -- -- -- -- -- -- 57 -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
70: -- -- -- -- -- -- -- --

I believe it could be fixed with i2cset in combination with hdmi_timings

My config:

# Add support for software i2c on gpio pins
dtoverlay=i2c-gpio,bus=2,i2c_gpio_sda=23,i2c_gpio_scl=24,i2c_gpio_delay_us=2
# DPI Video Setup

disable_overscan=0

# DPI Video Setup
dtoverlay=dpi18
overscan_left=0
overscan_right=0
overscan_top=0
overscan_bottom=0
framebuffer_width=854
framebuffer_height=480
enable_dpi_lcd=1
display_default_lcd=1
dpi_group=2
dpi_mode=87

dpi_output_format=458773
hdmi_timings=854 0 14 4 12 480 0 2 3 9 0 0 0 60 0 24595200 3

__________

sudo i2cset -y 2 0x1b 0x0c 0x00 0x00 0x00 0x13 i
sudo i2cset -y 2 0x1b 0x0b 0x00 0x00 0x00 0x00 i

__________

It works with settings for 640x360 and i2cset -y 2 0x1b 0x0c 0x00 0x00 0x00 0x7 i

Also I read the manual of DLPC2607 Programmer's Guide and tried some settings with no good result.

By the way 0x13 points to 800x480, I also tried that, and 0x19 at the end gives me lines in between...

  • Hello Maxim,

    I would like to confirm that you have attached grounds between the Rapsberry Pi and the DLP2000 EVM. When they aren't connected I have seen weird issues in the past.

    Thanks,
    Kyle

  • Kyle, thank you for fast reply

    I can confirm that ground are connected, I even tried to connect few of them > same result

    Thanks,

    Max

  • Update,

    I can confirm resolution issue, tested with 720x480 - it works with crop of the sides, aspect ratio 2 in timings and i2c with x09

    Still searching for a way to run at 854x480, which doesn't much standard respebian aspect ratio in timings.

    Looking forward for your recommendations.

  • Maxim,

    Instead of reducing the resolution, have you tried just relaxing the timings and reducing the pixel clock rate? As I mentioned in the other thread this is generally a timing issue when using jumpers.

    Regards,

    Philippe Dollo

  • Philippe, I checked that and it didn't work.

    Ocasionally, I tried settings 864x480 with i2cset code 15 and it worked.... It looks like I have some different numbers than in programmer's guide(why?). 

    Anyhow, now it works. Here are updated settings: 

    in config.txt:

    dtoverlay=i2c-gpio,bus=2,i2c_gpio_sda=23,i2c_gpio_scl=24,i2c_gpio_delay_us=2

    dtoverlay=dpi18
    overscan_left=0
    overscan_right=0
    overscan_top=0
    overscan_bottom=0
    framebuffer_width=864
    framebuffer_height=480

    enable_dpi_lcd=1

    display_default_lcd=1

    dpi_group=2
    dpi_mode=87

    dpi_output_format=458773
    dpi_timings=864 0 14 4 12 480 0 2 3 9 0 0 0 60 1 24883200 3

    and i2cset commands:

    sudo i2cset -y 2 0x1b 0x0c 0x00 0x00 0x00 0x15 i
    sudo i2cset -y 2 0x1b 0x0b 0x00 0x00 0x00 0x00 i

    Now I have the last(hopefully) issue with color banding, looks like I have to make a new topic for that.

  • Maxim,

    Thanks for your update on the issue. Hopefully these updated timings work for other users with a similar issue as well.

    Regards,

    Philippe Dollo