Memorial day is 05/25/2015 – Orders will ship out on May 26th. There will not be any deliveries or shipping on Monday. Any order placed after 11am ET on Friday May 22nd will not start to ship out until Tuesday May 26th.

Problem: EMIC2 + Arduino-Due + Level-Converter (TXB0108)
Moderators: adafruit_support_bill, adafruit

Problem: EMIC2 + Arduino-Due + Level-Converter (TXB0108)

by randomvibe on Sat Jan 19, 2013 5:36 am

I'm having intermittent problems with this setup: EMIC2 + Arduino-Due + Level-Converter (TXB0108). I traced it to the TXB0108. Background:

The EMIC2 works perfectly on its own when I interact with it using my desktop serial port and terminal program (PuTTy).

The Arduino-Due's hardware serial also works fine when I test it with my desktop and PuTTy.

The Adafruit TXB0108 between the Due and emic does not work. If I directly patch Due-TX to the EMIC-SIN pin (SIN is 3.3V compliant per spec), then It does work intermittently, however hangs now and then because the TXB0108 delays or completely fails to pass EMIC's ready-to-receive-command symbol.

All problems disappear when I directly patch Due-RX to EMIC-SOUT, and bypass TXB0108 completely. Now I risk damaging the Due.

The TBXB0108 is known to have issues with I2C. Is it known to have issues with the Arduino Due hardware serial ports? Do I need to add a resistors and/or other components somewhere? Thank you.
randomvibe
 
Posts: 43
Joined: Tue Jan 24, 2012 7:26 am

Re: Problem: EMIC2 + Arduino-Due + Level-Converter (TXB0108)

by adafruit on Sat Jan 19, 2013 8:49 am

Never heard of a problem with serial - do you have any pullups or anything?

adafruit
 
Posts: 11905
Joined: Thu Apr 06, 2006 4:21 pm
Location: nyc

Re: Problem: EMIC2 + Arduino-Due + Level-Converter (TXB0108)

by randomvibe on Sun Jan 20, 2013 2:38 am

adafruit wrote:Never heard of a problem with serial ...

Have you tried the TXB0108 through hardware serial? From an A-Due? A-Due's are very new I realize.

adafruit wrote: - do you have any pullups or anything?

No pullups, just A-Due to TXB to EMIC2. Are pullups required for serial? Anything else needed?

Or, is there a better option over the TXB0108 for this application? Thank you.
randomvibe
 
Posts: 43
Joined: Tue Jan 24, 2012 7:26 am

Re: Problem: EMIC2 + Arduino-Due + Level-Converter (TXB0108)

by adafruit on Sun Jan 20, 2013 12:33 pm

we have not tried it, but also don't know why it wouldn't work. you could try our FET based 4-channel shifter.

adafruit
 
Posts: 11905
Joined: Thu Apr 06, 2006 4:21 pm
Location: nyc

Re: Problem: EMIC2 + Arduino-Due + Level-Converter (TXB0108)

by randomvibe on Sun Jan 20, 2013 10:35 pm

adafruit wrote:Never heard of a problem with serial - do you have any pullups or anything?


Are you also suggesting I try to adding pullups? What value and on which side (3.3V, or 5V, or both)?
randomvibe
 
Posts: 43
Joined: Tue Jan 24, 2012 7:26 am

Re: Problem: EMIC2 + Arduino-Due + Level-Converter (TXB0108)

by adafruit_support_bill on Mon Jan 21, 2013 7:16 am

No, you should not need pullups for serial.

adafruit_support_bill
 
Posts: 37526
Joined: Sat Feb 07, 2009 10:11 am