1 The ACM driver works with modems and ISDN TAs that use the USB Abstract
2 Control Model standard.
4 ****************************
6 Watch out, the driver is not stable and tested. Sync often, make backups,
7 most importand: don't blame me...
10 mknod /dev/ttyACM0 c 166 0
11 mknod /dev/ttyACM1 c 166 1
12 mknod /dev/ttyACM2 c 166 2
13 mknod /dev/ttyACM3 c 166 3
14 Compile a kernel with support for your host controller (uhci only for now!)
15 and support for ACM. Boot this kernel. If you connect your device to the
16 USB bus you should see messages like the following:
18 Jul 19 20:14:29 office kernel: USB new device connect, assigned device number 1
19 Jul 19 20:14:29 office kernel: Found 02:09
20 Jul 19 20:14:29 office kernel: Found 04:09
21 Jul 19 20:14:29 office kernel: Found 05:07
22 Jul 19 20:14:29 office last message repeated 2 times
23 Jul 19 20:14:29 office kernel: parsed = 39 len = 67
24 Jul 19 20:14:29 office kernel: Expected descriptor 04/09, got 02/09 - skipping
25 Jul 19 20:14:29 office kernel: 0 09
26 Jul 19 20:14:29 office kernel: 1 02
27 Jul 19 20:14:29 office kernel: 2 43
28 Jul 19 20:14:29 office kernel: 3 00
29 Jul 19 20:14:29 office kernel: 4 02
30 Jul 19 20:14:29 office kernel: 5 02
31 Jul 19 20:14:29 office kernel: 6 04
32 Jul 19 20:14:29 office kernel: 7 60
33 Jul 19 20:14:29 office kernel: 8 00
34 Jul 19 20:14:29 office kernel: Found 04:09
35 Jul 19 20:14:29 office kernel: Found 02:09
36 Jul 19 20:14:29 office kernel: Found 04:09
37 Jul 19 20:14:29 office kernel: Found 05:07
38 Jul 19 20:14:29 office kernel: Found 04:09
39 Jul 19 20:14:29 office kernel: Found 05:07
40 Jul 19 20:14:29 office kernel: Found 05:07
41 Jul 19 20:14:29 office kernel: parsed = 67 len = 0
42 Jul 19 20:14:29 office kernel: getstringtable
43 Jul 19 20:14:29 office kernel: acm_probe
44 Jul 19 20:14:29 office kernel: USB ACM found
46 Watch out for the line:
47 Jul 19 20:14:29 office kernel: USB new device connect, assigned device number 1
49 Jul 19 20:14:29 office kernel: USB ACM found
50 These two lines show that the device was seen by the usb host controller and
51 then recognized by the acm driver as a valid device.
53 If you use a terminal emulation software like minicom with /dev/ttyACM0 you
54 should be able to send AT commands to your device and get responses. I've
55 been able to do zmodem downloads to another pc. However downloads from one
56 ISDN TA to another ISDN TA connected to the same PC didn't work. Don't
57 know why. Flow control is not finised after all and i'd guess there might
58 be problems on heavily loades PCs. I also did some tests with ppp but i'm
59 not finised with this. There might be a chance to get it working. However
60 i'd like to know if your device is recognized as an ACM device. I'm also
61 interested if the thing is stable or if it crashes.
62 (should i say how it crases?)
64 You should be able to add and remove devices from the bus. The driver will
65 always try to fill up unused ttys. This means if you hotplug devices their
66 order may have changed after reboot. This is not the behaviour Linus liked
67 to see but it's ok for now. (I hope ;-)
69 Please report your experiences to me:
72 ***************************
76 It should work with (That means i know these devices conform to ACM):
77 3Com Office Connect Modem
78 3Com Sportster USB (I think that's what it's called)
80 ***************************
81 Many thanks to 3Com which did not only support me with hardware but also
82 with technical support in USB questions. They also allowed me to do tests in
85 ***************************
87 Flow control not tested (likely not to work)
88 Some tty function calls not implemented (putchar, etc...)
89 Huge amounts of debug output (compile in [*] Magic SysRq key and press ALT+PRTSCR+0 )
90 Not all mem is freed at close (need terminate irq in hcd)
92 ***************************