Hello John, Sorry to bother you but i have a question regarding the input output features of the TXS0104 that you recommended me a while back. The problem is that i am doing some calculations for the decoupling network of the power regulator. And usually in this calculation i would determine voltage noise margins by seeing the input/output min and max voltage characteristics of the communicating ICs. Firstly i am not sure about the characteristics off the BeagleBone Black but looking at the processor datasheet i see a 2.85 min output high and a 0.45 max output low(correct me if i am wrong). Now according to the TXS0104 datasheet the min high input should be 2.9 and the max low input should be 0.15. These numbers seem too high and do not allow for any noise margin. I just want to know if i am reading the datasheet wrong somewhere because usually there is a noise margin even if just a little.
Sorry again for the bother but i really need to know if I am doing this right. Regards, Cristian 2014-07-03 21:41 GMT+02:00 John Syn <[email protected]>: > > From: Cristian Mitu <[email protected]> > Reply-To: "[email protected]" <[email protected]> > Date: Thursday, July 3, 2014 at 12:22 PM > To: "[email protected]" <[email protected]> > > Subject: Re: [beagleboard] UART RS485 transciever setup > > Thank you again Jhon you are a life saver this part looks perfect for what > i need. I think i will use two, one for the RX and TX signals seeing as it > doesn't need direction input and one for the DE and RE enable signals. > Thank you again > > Then use the TXS0104 > > Regards, > John > > > > PS > Also thank you Jerônimo for your suggestion. > > > 2014-07-03 20:53 GMT+02:00 John Syn <[email protected]>: > >> >> From: Jerônimo Lopes <[email protected]> >> Reply-To: "[email protected]" <[email protected]> >> Date: Thursday, July 3, 2014 at 5:31 AM >> To: "[email protected]" <[email protected]> >> Subject: Re: [beagleboard] UART RS485 transciever setup >> >> Cristian, >> >> >> 2014-07-03 8:55 GMT-03:00 Cristian Mitu <[email protected]>: >> >>> Thank you for your response John. >>> So i only need to to translate when sending data to the BBB or for >>> both TX and RX ? >>> >>> >> >> I'm using BBB with a 75176 transceiver (5V powered). Put a diode between >> BBB Rx and 75176: >> >> 75176------|<|------BBB Rx >> >> And a pullup resistor, from BBB Rx to 3.3V. >> >> It's working fine. >> >> Only for slow data speeds. >> >> >> >>> >>> >>> >>> 2014-07-03 5:18 GMT+02:00 John Syn <[email protected]>: >>> >>>> >>>> From: Cristian Mitu <[email protected]> >>>> Reply-To: "[email protected]" <[email protected]> >>>> Date: Wednesday, July 2, 2014 at 1:49 PM >>>> To: "[email protected]" <[email protected]> >>>> Subject: [beagleboard] UART RS485 transciever setup >>>> >>>> Hello guys, >>>> >>>> >>>> I am designing a board ( an adapter board for the BeagleBine black) >>>> that is un upgrade for a current system. Beacuse of this i specifically >>>> have to link a 5V TTL RS485 transceiver to one of the UARTs available. I am >>>> not sure what logic family the BeagleBone uses(though i'm guessing that it >>>> is CMOS) and because of this i want to know if this old transceiver can be >>>> wired directly to the BeagleBone or is it unavoidable that i have to use >>>> logic level translators for the signals. I apologize for the newbie >>>> question and i thank you in advance for your response. >>>> >>>> You will need to translate the 5V TTL signals to 3.3V before connecting >>>> to the BBB. >>>> >>>> Regards, >>>> John >>>> >>>> >>>> >>>> PS >>>> >>>> If you could direct me to some good drivers for RS485 communication i >>>> would be overwhelmed with joy and eternally grateful :) >>>> >>>> -- >>>> 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/tsrW0hBClBc/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. >> >> -- >> 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/tsrW0hBClBc/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/tsrW0hBClBc/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. 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