On 04/26/2016 11:56 AM, Paul Fulghum wrote: > I’ve taken this off list with Mark. I believe what is required is > configuring the n_hdlc line discipline module to use larger frame > sizes. n_hdlc defaults to 4K. Using 4K requires configuration of the > device driver (synclink_gt) and the line discipline (n_hdlc). > > I’ll continue to help Mark off list. Thanks, Paul. I totally overlooked the reference to hdlc (just read Mark's OP too fast). >> On Apr 26, 2016, at 11:46 AM, Peter Hurley <peter@xxxxxxxxxxxxxxxxxx> wrote: >> >> Hi Mark, >> >> On 04/26/2016 11:24 AM, Mark Hounschell wrote: >>> I am having some difficulties with a synklink_gt4 card and/or its >>> driver. I am trying to read/write 16384 byte frames. I seem to be >>> able to write them but can only read 4096 bytes of data per read. The >>> documentation I have for this card says I can have a MAX frame size >>> of between 4096 and 65535. And I see code in the driver that agrees >>> with that doc. I understand how to set the maxframe size for each >>> port properly but it doesn't seem to change this behavior. >>> >>> This is making things sort of awkward. I can write a single 16384 >>> byte frame, but to read 16384 bytes I have to issue 4 reads. I seem >>> to only be able to read a max of 4096 bytes. I sort of need a single >>> read to read a single frame as I am able to do with the writes. I >>> don't really know if this is a synclink driver issue or something in >>> the tty/hdlc layer. It actually looks to me like the synclink driver >>> its self is OK. Am I missing something? >> >> Normal tty use (with N_TTY line discipline) limits reads to 4096 bytes >> because that's how big the per-tty input buffer is. The value is not >> configurable. >> >> Regards, >> Peter Hurley > -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
