Thanks for your response.  I would very much like to get a few people
who know something about these issues thinking about what might be
happening, because I have no experience.

The problems I see are inability to dial out and garbled responses
from the phone.

On Wed, 6 Mar 2002, Brad Hards wrote:
> On Wed, 6 Mar 2002 08:30, Leif Jensen wrote:
> > T:  Bus=01 Lev=01 Prnt=01 Port=01 Cnt=02 Dev#=  4 Spd=12  MxCh= 0
> > D:  Ver= 1.10 Cls=02(comm.) Sub=02 Prot=00 MxPS= 8 #Cfgs=  1
> This is an illegal configuration from the Communication Device Class spec,
> Table 20. Sub has to be 00.

I was going by a list at the linux-usb site, but it must have contained
the table 15-17 info, which I now presume applies only to the I: line.
Is the spec on line?

> > C:* #Ifs= 2 Cfg#= 1 Atr=c0 MxPwr= 20mA
> > I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(comm.) Sub=02 Prot=01 Driver=(none)
> This is ACM, supporting Common AT commands (CDC Spec, tables 15, 16 and 17)
>
> > E:  Ad=88(I) Atr=03(Int.) MxPS=  16 Ivl= 10ms
> > I:  If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=00 Prot=00 Driver=serial
> > E:  Ad=01(O) Atr=02(Bulk) MxPS=  16 Ivl=  0ms
> > E:  Ad=82(I) Atr=02(Bulk) MxPS=  16 Ivl=  0ms
> >
> > Notice the data line has the serial driver, while comm has none.
> Forcing it doesn't really count :)

I knew this couldn't be a proper way to operate the modem.  It does at
least allow AT commands and responses to be exchanged.  This may be the
underlying reason I could not exchange data on incoming calls before,
since now the acm driver can do that (yay!).  How can I find out what
the E: lines mean?

> > Because of the two interfaces the phone presents I thought the acm
> > driver might not be a bad thing to try.  Unfortunately it won't
> > recognize it, but I found that modifying the source acm.c can fix this.
> Bad fix (you will break eveyone else's modem). Try specifying it like this:

Yes, I didn't intend this to be a patch for all to apply.  Understand
that I was excited to have made the driver work after reading a lot of
usb driver code for half an hour.

> > The most interesting behavior I saw was when I set the phone to answer
> > the next call as a data call and then called it with minicom from my
> > desktop computer on a landline.  The phone will send RING notices and
> > if you respond with ATA it will pick up and both ends report CONNECT.
> Looks like progress!

Since then I've been able to get a working incoming data connection
up at 14.4Kbps.  The fact that this basically works but I have no luck
making outgoing calls is very frustrating.  Out is the direction I want.
The incoming connection cannot be escaped by +++ as usual.  Is the
escape sequence not going over the right usb interface?

> > I have had no luck telling the phone to dial out with AT commands.  It
> > always reports NO CARRIER immediately.
> Strange. Maybe a config setting on the phone or the dialer?

I have since found some information on web sites about additional
AT-commands for CDMA phones and many of them also work.  AT+CDVxxxx
should dial xxxx as a voice call, but the response is "ERROR".

The two possibilites I see are

1) Data dialing is a premium service I'm not subscribed to.

2) Additional communication needed to enable dialing from data connection.

If I could get voice or fax dialing to work I would lean more towards 1.
The "NO CARRIER" response seems odd.  The provider's site is
disappointingly no help at all.

On the other hand there are no doubt many undocumented AT or other commands
and no way to discover them.

The other important issue is that the responses from the phone are often
garbled or accompanied by hundreds to thousands of repeated characters,
usually 'A' or newline or some charater from the command it received.
This is the same whether operated by the acm driver or a forced serial
driver.  Assuming there is no bug in the acm driver, this means the
phone must deviate somehow from the spec and will need its own driver
to communicate properly.

Best,
Leif



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