Hi Dave, Thanks for the info, however in my case I must say this does not look like the firmware issue mentioned below - I have tested this with UEFI and coreboot/seaBIOS and this makes no difference, unlike that stated in the ticket.
Based on the fact that there is a known issue ( https://bugzilla.yoctoproject.org/show_bug.cgi?id=7027) with the HDMI interface being out of spec and with the testing I have done everything points at a hardware problem. Some boards just about work, others don't at all. EDID is all working fine. Unless the HDMI drive strengths or levels can be adjusted by software, then I can't see how a firmware fix would improve anything here, any thoughts? Hence back to my earlier question about the A4 revision of the board with proper HDMI compliant signals - is this available yet? If so I can very easily check to see if this solves my problem. Thanks, Leigh On 7 Jun 2015 18:34, "Anders, David" <[email protected]> wrote: > Leigh, > > > > See this bug report: > > > > https://bugzilla.yoctoproject.org/show_bug.cgi?id=7719 > > > > specifically the TFP401 and TFP501 chips from TI are not working with the > MinnowBoard Max. the issue appears to be a firmware , not hardware issue, > and is being worked on… > > > > thanks > > Dave > > > > *From:* elinux-MinnowBoard [mailto: > [email protected]] *On Behalf Of *Leigh Gawne > *Sent:* Sunday, June 7, 2015 2:43 AM > *To:* MinnowBoard Development and Community Discussion > *Subject:* Re: [MinnowBoard] HDMI level shifters and revision A4 > > > > Hi Dave, > > I am using the TI TFP401 as the DVI decoder. > > I thought about spinning another revision of the board with an additional > level shifter, but given that these are present on the A4 revision, my > preference is just to get this revision and everything should play nice. > > Thanks, > > Leigh > > On 6 Jun 2015 11:21 pm, "Anders, David" <[email protected]> wrote: > > Leigh, > > > > We have found that there are some DVI receiver chips that are of issue > with the minnowboard max. which chipset are you using to covert from > HDMI/DVI to LVDS? > > > > Dave > > > > *From:* elinux-MinnowBoard [mailto: > [email protected]] *On Behalf Of *Leigh Gawne > *Sent:* Saturday, June 6, 2015 6:46 AM > *To:* [email protected] > *Subject:* [MinnowBoard] HDMI level shifters and revision A4 > > > > Hi guys, > > > > I have a customised daughterboard for the Minnoxboard Max which includes > an HDMI to LVDS subsystem. During test, I have found that some boards are > unable to drive the connected LCD display panel. Further investigation > leads me to believe that it is the missing level shifters on the > Minnowboard Max which mean that this is not working as expected (connecting > other HDMI sources to the board, i.e. PC, etc. work absolutely fine. > Inspection of the diff pair levels on a scope shows that it is definitely > marginal). > > > > I understand that revision A4 of the board ( > https://bugzilla.yoctoproject.org/show_bug.cgi?id=7027) will include > these level shifters. My question is whether this revision of the board is > available yet, and if so, how I couple go about ordering a couple of them > for test to ensure it solves my problem. I purchase around 10 boards around > a month or so ago, and these are all revision A2. > > > > Any insights or additional information would be most helpful. > > > > Regards, > > > > Leigh > > > _______________________________________________ > elinux-MinnowBoard mailing list > [email protected] > http://lists.elinux.org/mailman/listinfo/elinux-minnowboard > > > _______________________________________________ > elinux-MinnowBoard mailing list > [email protected] > http://lists.elinux.org/mailman/listinfo/elinux-minnowboard > >
_______________________________________________ elinux-MinnowBoard mailing list [email protected] http://lists.elinux.org/mailman/listinfo/elinux-minnowboard
