Hi, I was a Google Summer of Code student writing drivers for the Minix operating system last summer. I was working on implementing EDID reading (i.e. getting the supported resolutions, etc from the connected display/monitor via the HDMI chip). I searched far and wide and there isn't documentation with register definitions for the TDA19988. I sort of had to piece things together using the datasheet for a similar chip (TDA9983B), that pre-production draft of the TDA19988 datasheet (I think it's the one you are referring to), some example code from NXP (Google search for LPC4350_FPU_TFT_HDMI-v2.0.zip), and the Linux driver sources. I've contacted the author of the Linux driver and various people at BeagleBoard.org and that's the only documentation available. Well, there is the Minix driver now but it only does EDID reading at the moment (no hdmi output as there isn't a driver for the am335x lcd controller yet for Minix).
As for initializing the chip. Yes, there are several commands you need to send it via I2C to turn on the HDMI interface and configure the output. Thomas On Saturday, January 18, 2014 3:26:27 PM UTC-5, Travis Estep wrote: > > Hello! I've been hacking around with the BBB for some time now, mostly > doing bare metal programming. On other boards that I build projects with, I > usually use one of my TFTs that I have laying around and use my custom > graphical interface for the UI part. But the BBB is different. While I have > been able to use a TFT with it, I'd like to get the HDMI up and running on > bare metal if possible. Looking over the datasheet for the TDA19988BHN I > can see that basically it just takes the LCD RGB signals and concerts that > to HDMI output. However, I have not had any luck with feeding it from the > library I wrote for my TFT. Is there something different I need to do with > the signals? Does the HDMI chip require some kind of initialization before > being used? The datasheet I have is one that I found on some third party > website and I suspect it may be incomplete. I can't find the official > datasheet on NXP's website at all. > > Any help would be appreciated. Any advice for anyone else who has had > success in this arena would also be much appreciated. Thanks in advance! > > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
