Reply by Rich Webb December 12, 20082008-12-12
On Fri, 12 Dec 2008 09:17:05 +0100, "Meindert Sprang"
<ms@NOJUNKcustomORSPAMware.nl> wrote:

>"Rich Webb" <bbew.ar@mapson.nozirev.ten> wrote in message >news:p7g2k4ldat80uo76c70sd1fj1n5klfskv8@4ax.com... >> On Thu, 11 Dec 2008 13:37:47 +0100, Stef >> <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote: >> >> Still there as of XP embedded. We ended up isolating the serial data >> lines until XPe told the front panel controller "Hey, I'm awake," at >> which time we would allow the NMEA strings to be passed. Annoying. > >Windows outputs a special serial enumeration sequence on the DTR and RTS >lines during startup. When you block the RxD line during this activity, >Windoze will not interpret incoming data as a mouse. A small PIC of some >sort could be programmed to do this. > >This is all nicely documented in the "Plug and Play External COM Device >Specification" from Microsoft.
Thanks for the info. In that specific application, we already had a "listening watch" on a serial port from the XPe for other status info and were able to use that as the port enable. Hmm... but use the dance of the DTR & RTS lines to a retriggerable used as a gate disable. -- Rich Webb Norfolk, VA
Reply by Stef December 12, 20082008-12-12
In comp.arch.embedded,
Meindert Sprang <ms@NOJUNKcustomORSPAMware.nl> wrote:
> "Rich Webb" <bbew.ar@mapson.nozirev.ten> wrote in message > news:p7g2k4ldat80uo76c70sd1fj1n5klfskv8@4ax.com... >> On Thu, 11 Dec 2008 13:37:47 +0100, Stef >> <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote: >> >> Still there as of XP embedded. We ended up isolating the serial data >> lines until XPe told the front panel controller "Hey, I'm awake," at >> which time we would allow the NMEA strings to be passed. Annoying. > > Windows outputs a special serial enumeration sequence on the DTR and RTS > lines during startup. When you block the RxD line during this activity, > Windoze will not interpret incoming data as a mouse. A small PIC of some > sort could be programmed to do this. > > This is all nicely documented in the "Plug and Play External COM Device > Specification" from Microsoft.
Nice to know that it's there, but no solution if you just have all sorts of serial stuff that may be spitting out data when you boot your PC. Why can't the serial mouse driver not at least check the incoming data and decide there is no mouse data it can sensibly use? Just invoking random cursor movements on random incoming data doesn't sound like solid design. -- Stef (remove caps, dashes and .invalid from e-mail address to reply by mail) A budget is just a method of worrying before you spend money, as well as afterward.
Reply by Meindert Sprang December 12, 20082008-12-12
"Frank-Christian Kruegel" <dontmailme@news.invalid> wrote in message
news:14j2k4pkr8of939e05a78j2go3kqcskogc@4ax.com...
> > Don't you know the boot.ini switches /FASTDETECT and /NOSERIALMICE? > > http://technet.microsoft.com/en-us/sysinternals/bb963892.aspx
Yes, and for some dark reason, these options do sometimes work, sometimes they don't. Meindert
Reply by Meindert Sprang December 12, 20082008-12-12
"Rich Webb" <bbew.ar@mapson.nozirev.ten> wrote in message
news:p7g2k4ldat80uo76c70sd1fj1n5klfskv8@4ax.com...
> On Thu, 11 Dec 2008 13:37:47 +0100, Stef > <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote: > > Still there as of XP embedded. We ended up isolating the serial data > lines until XPe told the front panel controller "Hey, I'm awake," at > which time we would allow the NMEA strings to be passed. Annoying.
Windows outputs a special serial enumeration sequence on the DTR and RTS lines during startup. When you block the RxD line during this activity, Windoze will not interpret incoming data as a mouse. A small PIC of some sort could be programmed to do this. This is all nicely documented in the "Plug and Play External COM Device Specification" from Microsoft. Meindert
Reply by Meindert Sprang December 12, 20082008-12-12
"Mark Borgerson" <mborgerson@comcast.net> wrote in message
news:MPG.23a9fef3f8e7446b989686@news.motzarella.org...
> > I just heard once again today, of the problems that can occur if your > USB serial port is receiving data when you plug in the USB side. > Apparently, it can make the serial port act like a mouse if there > is serial data arriving when the USB side is enumerating. I > don't know if it was an FTDI-based USB-Serial converter, but I know > that happens with FTDI chips. Apparently the internal state machine > isn't able to enumerate and process incoming data at the same time.
That is not an FTDI problem but a windows problem (the infamous Crazy Mouse problem). It also happens when you start W2K and XP while serial data already comes in on *any* serial port. As a matter of fact, you can tweak the INF files of the FTDI driver to prevent this problem by disabling the serial enumerator in windows for that specific port. We do this in our products as well, which makes the USB versions of our NMEA multiplexers work better than the RS-232 versions. Meindert
Reply by Rich Webb December 11, 20082008-12-11
On Thu, 11 Dec 2008 18:24:05 +0100, Frank-Christian Kruegel
<dontmailme@news.invalid> wrote:

>On Thu, 11 Dec 2008 11:38:21 -0500, Rich Webb <bbew.ar@mapson.nozirev.ten> >wrote: > >>On Thu, 11 Dec 2008 13:37:47 +0100, Stef >><stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote: >> >>>That may be a Windows problem and happens not only with FTDI or even >>>USB stuff. Windows has always had problems when serial data comes in >>>during boot. Last time I experienced it was a year ago with W2000 and >>>a serial GPS. If the GPS was on during boot (and thus spitting out NEMA >>>sentences), it was detected as a mouse and the cursor would move >>>randomly over the screen (the serial mouse driver does little data >>>checking aparently). Have not tested this with XP or Vista, but I doubt >>>there will be much change as this behaviour has not changed since W3.1 >>>(or even earlier?). >> >>Still there as of XP embedded. We ended up isolating the serial data >>lines until XPe told the front panel controller "Hey, I'm awake," at >>which time we would allow the NMEA strings to be passed. Annoying. > >Don't you know the boot.ini switches /FASTDETECT and /NOSERIALMICE? > >http://technet.microsoft.com/en-us/sysinternals/bb963892.aspx
Yes, and I also know that those switches don't work on all machines; BIOS variations, sensitivity to initial conditions, race conditions, phase of the moon, who knows? Believe me, isolating the serial data lines was NOT our first choice but it was the only method that worked reliably. -- Rich Webb Norfolk, VA
Reply by Frank-Christian Kruegel December 11, 20082008-12-11
On Thu, 11 Dec 2008 11:38:21 -0500, Rich Webb <bbew.ar@mapson.nozirev.ten>
wrote:

>On Thu, 11 Dec 2008 13:37:47 +0100, Stef ><stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote: > >>That may be a Windows problem and happens not only with FTDI or even >>USB stuff. Windows has always had problems when serial data comes in >>during boot. Last time I experienced it was a year ago with W2000 and >>a serial GPS. If the GPS was on during boot (and thus spitting out NEMA >>sentences), it was detected as a mouse and the cursor would move >>randomly over the screen (the serial mouse driver does little data >>checking aparently). Have not tested this with XP or Vista, but I doubt >>there will be much change as this behaviour has not changed since W3.1 >>(or even earlier?). > >Still there as of XP embedded. We ended up isolating the serial data >lines until XPe told the front panel controller "Hey, I'm awake," at >which time we would allow the NMEA strings to be passed. Annoying.
Don't you know the boot.ini switches /FASTDETECT and /NOSERIALMICE? http://technet.microsoft.com/en-us/sysinternals/bb963892.aspx Mit freundlichen Gr&#4294967295;&#4294967295;en Frank-Christian Kr&#4294967295;gel
Reply by Rich Webb December 11, 20082008-12-11
On Thu, 11 Dec 2008 13:37:47 +0100, Stef
<stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote:

>That may be a Windows problem and happens not only with FTDI or even >USB stuff. Windows has always had problems when serial data comes in >during boot. Last time I experienced it was a year ago with W2000 and >a serial GPS. If the GPS was on during boot (and thus spitting out NEMA >sentences), it was detected as a mouse and the cursor would move >randomly over the screen (the serial mouse driver does little data >checking aparently). Have not tested this with XP or Vista, but I doubt >there will be much change as this behaviour has not changed since W3.1 >(or even earlier?).
Still there as of XP embedded. We ended up isolating the serial data lines until XPe told the front panel controller "Hey, I'm awake," at which time we would allow the NMEA strings to be passed. Annoying. -- Rich Webb Norfolk, VA
Reply by Grant Edwards December 11, 20082008-12-11
On 2008-12-11, Stef <stef33d@yahooI-N-V-A-L-I-D.com.invalid> wrote:
> Mark Borgerson <mborgerson@comcast.net> wrote: > >> I just heard once again today, of the problems that can occur >> if your USB serial port is receiving data when you plug in the >> USB side. Apparently, it can make the serial port act like a >> mouse if there is serial data arriving when the USB side is >> enumerating. > > That may be a Windows problem and happens not only with FTDI > or even USB stuff. Windows has always had problems when serial > data comes in during boot.
It's definitely a windows problem, and it occurs with all serial ports. My empolyer makes serial ports attached via various buses (ISA, PCI, USB, Ethernet), and if there's data coming in when Windows starts up the port, Windows decides it's a mouse. It's a bug in Windows, and it's always been there.
> A USB attach may trigger the same sequence of events as during boot to > try and detect what is attached and cause the same effect.
Probably. The Windows serial device drive framework is pretty FUBAR (and has been for decades). -- Grant Edwards grante Yow! HUMAN REPLICAS are at inserted into VATS of visi.com NUTRITIONAL YEAST ...
Reply by Stef December 11, 20082008-12-11
In comp.arch.embedded,
Mark Borgerson <mborgerson@comcast.net> wrote:
>> > I just heard once again today, of the problems that can occur if your > USB serial port is receiving data when you plug in the USB side. > Apparently, it can make the serial port act like a mouse if there > is serial data arriving when the USB side is enumerating. I > don't know if it was an FTDI-based USB-Serial converter, but I know > that happens with FTDI chips. Apparently the internal state machine > isn't able to enumerate and process incoming data at the same time.
That may be a Windows problem and happens not only with FTDI or even USB stuff. Windows has always had problems when serial data comes in during boot. Last time I experienced it was a year ago with W2000 and a serial GPS. If the GPS was on during boot (and thus spitting out NEMA sentences), it was detected as a mouse and the cursor would move randomly over the screen (the serial mouse driver does little data checking aparently). Have not tested this with XP or Vista, but I doubt there will be much change as this behaviour has not changed since W3.1 (or even earlier?). A USB attach may trigger the same sequence of events as during boot to try and detect what is attached and cause the same effect. -- Stef (remove caps, dashes and .invalid from e-mail address to reply by mail) How do you power off this machine? -- Linus, when upgrading linux.cs.helsinki.fi, and after using the machine for several months