Re: [Gpsbabel-misc] Problems with GPS II

[John C. <jo...@jc...>]

On Thu, 31 May 2007 16:17:47 -0500
Robert Lipe <rob...@us...> wrote:

> What you're describing doesn't look like a Garmin problem nearly as much
> as a bad serial driver. Is this some USB/Serial adapter or multiport
> board or such?

Hi Robert.

Had a busy week and missed you reply - thanks!

No USB/Serial driver. It's a direct connection to the standard ttyS0 port.

> The problem with O_NDELAY is that it lets writes return when they're
> only partially satisfied and exactly none of our code is prepared to
> handle that - that's why it was removed.
> 
> write(X, buf, 1024)
> could write the first 32 bytes and return 32 - we never try to send
> the remainder.

Yep, I know. I once experimented a bit with those functions. Maybe the
NDELAY isn't necessary, and only the other option (O_NOCTTY) made things
work. Still, it's a fact that things started working from the moment I put
those back in.

With modern 16550's though, those with 64-byte FIFOs, it's quite unlikely
things would get lost (unless uploading large packets, but is there
actually any packet larger than 64?)

Cheers,
John