I have a Motorola Atrix Lapdock connected to my Raspberry Pi using the instructions provided on various web sites including http://rpidock.blogspot.com/.
The HDMI output initially displays on the Lapdock, but if I close the Lapdock and reopen it the video will not display. I find that sometimes rebooting the Pi or completely disconnecting the Lapdock (both USB and HDMI connections) will cause the display to work again.
I've even tried setting "hdmi_safe=1" to get the display to consistently work after closing and reopening the Lapdock or rebooting the Pi.
Could I just have a flaky Lapdock? I guess that I need to connect the Lapdock to a different HDMI source to see it behaves opening and closing the Lapdock.
Are there any other config.txt commands that I should try?
Are there any command line commands that I can run while SSH'ed into my Pi to check the status of the HDMI output?
Update (2013-07-16):
Can anyone with a working Lapdock perform the tvservice -d edit.out command parsing the output using edidparser edid.out posting your results here for comparison?
Using the tvservice -d edid.outcommand I was able to dump the EDID information from my Lapdoc, here is what that was returned:
johnma@raspberrypi:~$ edidparser edid.out
Enabling fuzzy format match...
Parsing d.out...
HDMI:EDID version 1.3, 1 extensions, screen size 26x14 cm
HDMI:EDID features - videodef 0x80 !standby !suspend !active off; colour encoding:RGB444|YCbCr422; sRGB is not default colourspace; preferred format is native; does not support GTF
HDMI:EDID found monitor S/N descriptor tag 0xff
HDMI:EDID found monitor range descriptor tag 0xfd
HDMI:EDID monitor range offsets: V min=0, V max=0, H min=0, H max=0
HDMI:EDID monitor range: vertical is 50-75 Hz, horizontal is 30-85 kHz, max pixel clock is 150 MHz
HDMI:EDID monitor range does not support GTF
HDMI:EDID found monitor name descriptor tag 0xfc
HDMI:EDID monitor name is MotoAttach
HDMI:EDID found preferred DMT detail timing format: 1366x768p @ 60 Hz (86)
HDMI:EDID established timing I/II bytes are 00 00 00
HDMI:EDID standard timings block x 8: 0x0101 0101 0101 0101 0101 0101 0101 0101
HDMI:EDID parsing v3 CEA extension 0
HDMI:EDID monitor support - underscan IT formats:no, basic audio:yes, yuv444:yes, yuv422:yes, #native DTD:1
HDMI:EDID found DMT detail timing format: 1366x768p @ 60 Hz (86)
HDMI:EDID failed to find a matching detail format for 0x720p hfp:110 hs:40 hbp:-134 vfp:5 vs:5 vbp:20 pixel clock:0 MHz
HDMI:EDID calculated refresh rate is 0 Hz
HDMI:EDID guessing the format to be 0x720p @24 Hz
HDMI:EDID found unknown detail timing format: 0x720p hfp:110 hs:40 hbp:-134 vfp:5 vs:5 vbp:20 pixel clock:0 MHz
HDMI:EDID failed to find a matching detail format for 0x1080i hfp:88 hs:44 hbp:-116 vfp:2 vs:5 vbp:16 pixel clock:0 MHz
HDMI:EDID calculated refresh rate is 0 Hz
HDMI:EDID guessing the format to be 0x1080i @24 Hz
HDMI:EDID found unknown detail timing format: 0x1080i hfp:88 hs:44 hbp:-116 vfp:2 vs:5 vbp:16 pixel clock:0 MHz
HDMI:EDID found CEA format: code 1, 640x480p @ 60Hz
HDMI:EDID found CEA format: code 3, 720x480p @ 60Hz
HDMI:EDID found CEA format: code 18, 720x576p @ 50Hz
HDMI:EDID found audio format 2 channels PCM, sample rate: 32|44|48|96|192 kHz, sample size: 16|20|24 bits
HDMI:EDID found HDMI VSDB length 5
HDMI:EDID HDMI VSDB has physical address 1.0.0.0
HDMI:EDID HDMI VSDB has no extension fields
HDMI:EDID adding mandatory support for DMT (4) 640x480p @ 60Hz
HDMI:EDID adding mandatory support for CEA (2) 720x480p @ 60Hz
HDMI:EDID adding mandatory support for CEA (17) 720x576p @ 50Hz
HDMI:EDID filtering formats with pixel clock > 162 MHz or h. blanking > 1023
HDMI:EDID best score mode initialised to DMT (4) 640x480p @ 60 Hz with pixel clock 25 MHz (score 0)
HDMI:EDID best score mode is now CEA (1) 640x480p @ 60 Hz with pixel clock 25 MHz (score 43432)
HDMI:EDID best score mode is now CEA (2) 720x480p @ 60 Hz with pixel clock 27 MHz (score 45736)
HDMI:EDID CEA mode (3) 720x480p @ 60 Hz with pixel clock 27 MHz has a score of 45736
HDMI:EDID DMT mode (4) 640x480p @ 60 Hz with pixel clock 25 MHz has a score of 36864
HDMI:EDID CEA mode (17) 720x576p @ 50 Hz with pixel clock 27 MHz has a score of 45736
HDMI:EDID CEA mode (18) 720x576p @ 50 Hz with pixel clock 27 MHz has a score of 45736
HDMI:EDID best score mode is now DMT (86) 1366x768p @ 60 Hz with pixel clock 72 MHz (score 5188835)
HDMI:EDID preferred mode remained as DMT (86) 1366x768p @ 60 Hz with pixel clock 72 MHz
HDMI:EDID has HDMI support and audio support
edid_parser exited with code 0
Update (2013-07-28):
Partial success! I am able to get the display to work consistently if I execute the following commands:
tvservice -e "DMT 4"
That commands sets the following profile:
tvservice -s
state 0x12001a [HDMI DMT (4) RGB full 4:3], 640x480 @ 60Hz, progressive
Then to get the display to appear I need to execute the following frame buffer command:
fbset 640x480-60
fbset --show
mode "640x480-60"
# D: 25.175 MHz, H: 31.469 kHz, V: 59.940 Hz
geometry 640 480 640 480 8
timings 39722 48 16 33 10 96 2
accel true
rgba 8/0,8/0,8/0,0/0
endmode
I am, however, unable to get the display to work consistently at its native resolution of 1366x768. My /etc/fb.modes file does not contain any entry for 1366x768.
Can someone with a working Atrix lapdock post the output of the following command:
fbset --show
Thank you!
Update (2013-07-30):
More success!
I am able to reliably get the Lapdock to display HDMI video using 1280x720 resolution. I achieve this using the following parameters in my /boot/config.txt file:
# Force DMT mode 85 HDMI
hdmi_group=2
hdmi_mode=85
hdmi_drive=2
# Ignore the devices EDID information
hdmi_ignore_edid=0xa5000080
tvservice -s returns:
state 0x12001a [HDMI DMT (85) RGB full 16:9], 1280x720 @ 60Hz, progressive
fbset --show returns:
mode "1280x720"
geometry 1280 720 1280 720 16
timings 0 0 0 0 0 0 0
rgba 5/11,6/5,5/0,0/16
endmode
I get no video display when using DMT mode (86) 1366x768 @ 60Hz which is supposed to be the native size of the display.
Could this be a problem with my HDMI cable connection? Could my exising HDMI cable and HDMI micro adapter have some bandwidth limitation that is preventing 1366x768 resolution from being displayed?
