It already is powered from 1.8V. The processor however, is powered from 3.3V. The NXP part is 3.3V tolerant.
You need the buffer to clean up the signals and provide better drive as is being done on the LCD boards.. I just designed the BeagleBone Black. You are designing your mother board so do as you see fit. Gerald On Wed, Oct 8, 2014 at 1:37 PM, Bremenpl <[email protected]> wrote: > Cant I just power the NXP from 1.8V? If the lines are 1.8V I would need > no translation then. Also there are no buffer on the bbb itself so why > would I need such? > > Dnia 8 października 2014 20:12:06 Gerald Coley <[email protected]> > napisał(a): > >> It is the low voltage level as these are 1.8V inputs. The issue is making >> sure you get low enough, fast enough due to capacitance and at the correct >> frequency to yield a good data integrity. You can try using a translator >> buffer from 3.3V to 1.8V. That should help. >> >> >> Gerald >> >> >> On Wed, Oct 8, 2014 at 12:55 PM, Bremenpl <[email protected]> wrote: >> >>> I could do buffers as well, thats not a problem. I am building the >>> board from scratch. Besides, arent the nxp input very high impedance? >>> >>> Dnia 8 października 2014 19:52:48 Gerald Coley <[email protected]> >>> napisał(a): >>> >>>> I am talking about you adding two NXP parts on those lines as you >>>> indicated that you were doing. LCD cape uses buffers do boost the signal. >>>> The NXP pins are 1.8V inputs. >>>> >>>> Gerald >>>> >>>> On Wed, Oct 8, 2014 at 12:38 PM, Bremenpl <[email protected]> wrote: >>>> >>>>> There are resistors on the lines, worse case scenarion I can take >>>>> them off. But tgose lines are used for lcd cape already so it does work, >>>>> whats the problem? >>>>> >>>>> Dnia 8 października 2014 19:06:54 Gerald Coley <[email protected]> >>>>> napisał(a): >>>>> >>>>>> I doubt it will work but you are free to try. Adding two loads such >>>>>> as that on those pins is asking for trouble. >>>>>> >>>>>> Gerald >>>>>> >>>>>> >>>>>> On Wed, Oct 8, 2014 at 1:50 AM, bremenpl <[email protected]> wrote: >>>>>> >>>>>>> Hello there, >>>>>>> I am currently working on a motherboard for the BeagleBone Black. >>>>>>> One of the requiments is to have a HDMI output on the side of the >>>>>>> motherboard. I Know that there are LCD pins on the BeagleBone Black >>>>>>> header >>>>>>> and there is a possibility to connect a LCD cape. I was wondering >>>>>>> either it >>>>>>> would work to duplicate the NXP HDMI framer circuit that is on the >>>>>>> board to >>>>>>> the motherboard and use it for hdmi output? If I am correct the only >>>>>>> difference would be that there is no acces to I2C0 from headers so I >>>>>>> would >>>>>>> have to use I2C1/2 for the NXP chip. That way at least I wont chave to >>>>>>> worry about addressing 2 chips at once (not sure If you can change >>>>>>> address >>>>>>> of the hdmi framer yet). >>>>>>> >>>>>>> My question is, would this solution be bard to implement in >>>>>>> software, or is it easy to change the I2C bus config for hdmi? Are there >>>>>>> any obstacles that I am not aware of? I would really aprichiate any >>>>>>> help in >>>>>>> here. >>>>>>> >>>>>>> -- >>>>>>> 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/d/optout. >>>>>>> >>>>>> >>>>>> -- >>>>>> For more options, visit http://beagleboard.org/discuss >>>>>> --- >>>>>> You received this message because you are subscribed to a topic in >>>>>> the Google Groups "BeagleBoard" group. >>>>>> To unsubscribe from this topic, visit >>>>>> https://groups.google.com/d/topic/beagleboard/85MgiQg0wJY/unsubscribe >>>>>> . >>>>>> To unsubscribe from this group and all its topics, send an email to >>>>>> [email protected]. >>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>> >>>>> -- >>>>> 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/d/optout. >>>>> >>>> >>>> -- >>>> For more options, visit http://beagleboard.org/discuss >>>> --- >>>> You received this message because you are subscribed to a topic in the >>>> Google Groups "BeagleBoard" group. >>>> To unsubscribe from this topic, visit >>>> https://groups.google.com/d/topic/beagleboard/85MgiQg0wJY/unsubscribe. >>>> To unsubscribe from this group and all its topics, send an email to >>>> [email protected]. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> -- >>> 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/d/optout. >>> >> >> -- >> For more options, visit http://beagleboard.org/discuss >> --- >> You received this message because you are subscribed to a topic in the >> Google Groups "BeagleBoard" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/beagleboard/85MgiQg0wJY/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> > -- > 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/d/optout. > -- 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/d/optout.
