I suspect that your LCD design is interfering with the boot pins that are co-located with the LCD pins which is changing the boot order.
I suggest that you read the System Reference Manual for more information. Gerald On Thu, Apr 16, 2015 at 11:49 AM, <lix...@gmail.com> wrote: > Hello, Everyone. > > I am in the very early stages of interfacing the BBB with a new 4.3" TFT > LCD, not a cape. It has a 16-bit data bus setup for 6800 style interface > with the onboard controller (SSD1963). This winds up requiring 22 GPIO > pins. I have been an engineer in the LCD industry for 6 years now, so I > know my way around most types of LCDs and configurations...but I am a > relative newbie to the BBB. > > I have disabled the HDMI port in the uenv.txt file and have confirmed it > to be disabled. The 6 control lines are connected to P8 pins 9-14, and the > 16 data pins are connected to P8 pins 29-44. 3.3V power is taken from P9 > and GND is taken from P8. When I physically connect the display to these > pins, the board does not boot. I get an LED to come up but then it seems > to pause and never boot. The display requires a max current of 220mA which > I know is close to the limit for the 3.3V supply, so I left the connections > made, but removed the power to the LCD. Same issue. I checked for shorts > on the connections...none that I could find. There is NO buffer between > the LCD and the uC as the boards have not been spun yet. I am hooking it > up using an FPC-to-wire converter cable. > > Given my relative noobishness to the BBB hardware, I was hoping someone > would have some fundamental oversight I am making here. > > Thanks. > > -- > 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 beagleboard+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- Gerald ger...@beagleboard.org http://beagleboard.org/ http://circuitco.com/support/ -- 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 beagleboard+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
