Re: [NTLK] Using UnixNPI at 230400bps?

From: Vladimir Alexiev (
Date: Thu Mar 21 2002 - 20:00:38 EST

> > > definition for 230400.. added one using
> > > the same flags as 256000.. and hey,
> > > whaddya know, it works.

Yes, however it doesn' t improve the speed for me. Here's the time
required to transfer 172k, as reported by \bin\cygwin\time:
57600 49
115200 33.5
230400 33.5
Using "start /realtime" improves the time by about 1s, but this
measurement probably isn't very accurate.

This makes 3.5kB/s for the slow speed and 5.1kB/s for the faster
speeds. But 57600bps should give about 5.7kB/s (assuming 1 start and 1
stop bit), so some speed is lost somewhere... (The time includes
connection, handshake and finish-up, so I thought the transfer rate on
bigger files will be better, but on a 1.5Mb file I got 5.6kB/s).

In fact I can start ser230400 on Newton and "unixnpi -s 230400" on the
PC and they connect fine. So I guess my cygwin libraries may be
downgrading the speed. Time to upgrade my cygwin?


Victor> I did have to upgrade my cygwin1.dll - I had an old one > lying around and it didn't work.

Indeed, the version makes all the difference: > filever \cygwin\bin\cygwin1.dll --a-- W32i DLL ENU 1003.2.0.0 shp 694,064 05-20-2001 cygwin1.dll This one didn't work, it doesn't seem to have /dev/ttyS0

> filever cygwin1.dll ----- W32i DLL ENU 1003.9.0.0 shp 768,840 03-19-2002 cygwin1.dll This is the one you supplied and it works ok. This fact bears mentioning in the README.


Hendrik> I sat down yesterday and wrote a simple GUI wrapper in Java

All the GUI I need is a shortcut like this on my desktop: unixnpi -s 230400 -d /dev/ttyS0 %1 %2 %3 %4 %5 %6 %7 %8 %9 (optionally, prepend "cmd -c start /realtime ").


Please find below a little patch to make an error message more correct: If you run > myunixnpi.exe -s 115200 -d /dev/ttyNOSUCH whatever.pkg then instead of "Error in opening Newton device!! Do you have a symlink to /dev/newton?" which is incorrect, it says: "Error in opening Newton device /dev/ttyNOSUCH!!"

if((newtFd = InitNewtDev(&newtDevInfo)) < 0) { char sErr[300]; sprintf (sErr, "Error in opening Newton device %s!!", newtDevInfo.devName); if (strcmp (newtDevInfo.devName, "/dev/newton")==0) strcat(sErr,"\nDo you have a symlink to /dev/newton?"); ErrHandler(sErr); }

-- Read the List FAQ/Etiquette: Read the Newton FAQ: This is the NewtonTalk mailing list -

This archive was generated by hypermail 2.1.2 : Tue Apr 02 2002 - 14:03:21 EST