Thanks for the confirmation. I have a logic analyzer and will dig further into things that way. Likely the problem is on my end.
Thanks! Mark. On Wed, 15 Apr 2015 at 13:53 Ytai Ben-Tsvi <[email protected]> wrote: > The lag bytes feature is merely an optimization, completely functionally > equivalent to you manually discarding a number of leading bytes from the > response. The optimization works by simply discarding those bytes on the > IOIO side, so that they don't have to be sent to the client (Android/PC) > and discarded there. > The IOIO is a SPI master, so it should be immune to any timing-related > problems (since it is driving the clock). > Seems like there's something else going on. Ideally, if you have access to > a logic analyzer, you can probe the SPI lines and figure out what's wrong. > Otherwise, just try to really simplify your program to zero in on the > problem. What sort of incorrect data are you getting? Are you running at > high frequencies (multiple MHz)? If so, are you confident about your signal > integrity? > > On Tue, Apr 14, 2015 at 8:26 PM, <[email protected]> wrote: > >> Hi All, >> >> I am trying to implement a fairly high bandwidth SPI data connection and >> I am a bit unclear on the "lag bytes" mentioned in the wiki. My device >> typically has 0 lag bytes, but if I assume 0 lag bytes, the data I read >> back is incorrect. Is there a fixed number of lag bytes inherent to the >> IOIO-OTG that I need to account for? I'm not seeing any padding (none of >> the data is 0xFF, so I am assuming that there are no lag bytes, as I would >> expect from my device, but the fact that the data appears to be wrong makes >> me think otherwise. But I may have other issues I have yet to figure out. >> I would like to clear up the bit about lag bytes though. Should I account >> for any on the ioio side of things? Any advice would be appreciated. >> >> Thanks, >> Mark. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "ioio-users" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/ioio-users. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to the Google Groups > "ioio-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/ioio-users. > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "ioio-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/ioio-users. For more options, visit https://groups.google.com/d/optout.
