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Old 08-15-2016, 04:58 PM   #1
JoseKreif
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Finding device in /dev


I have a modem connected with a Serial-to-USB cord. If I use

Code:
lsusb
I get

Code:
Bus 001 Device 003: ID 0951:1643 Kingston Technology
Bus 001 Device 001: ID 0000:0000
Bus 002 Device 001: ID 0000:0000
Bus 002 Device 002: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Bus 004 Device 001: ID 0000:0000
Bus 005 Device 001: ID 0000:0000
Bus 003 Device 001: ID 0000:0000
I am trying to find out which device is
Code:
Bus 002 Device 002: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
---

Code:
[root@plant01 dev]# ls
adsp          dvd-sr0        esp22  esp39  esp55     fd0u1440    input    nst0      ram1     root        st0l    tty18  tty34  tty50  ttyQ01e0  ttyQ02e2  ttyQ04e4        usbdev2.2_ep02  vcsa2
agpgart       dvdwriter      esp23  esp4   esp56     fd0u1680    kmsg     nst0a     ram10    rtc         st0m    tty19  tty35  tty51  ttyQ01e1  ttyQ02e3  ttyQ04e5        usbdev2.2_ep81  vcsa3
audio         dvdwriter-sr0  esp24  esp40  esp57     fd0u1722    log      nst0l     ram11    scd0        stderr  tty2   tty36  tty52  ttyQ01e2  ttyQ02e4  ttyQ04e6        usbdev2.2_ep83  vcsa4
autofs        esp            esp25  esp41  esp58     fd0u1743    loop0    nst0m     ram12    sda         stdin   tty20  tty37  tty53  ttyQ01e3  ttyQ02e5  ttyQ04e7        usbdev3.1_ep00  vcsa5
bus           esp1           esp26  esp42  esp59     fd0u1760    loop1    null      ram13    sda1        stdout  tty21  tty38  tty54  ttyQ01e4  ttyQ02e6  ttyS0           usbdev3.1_ep81  vcsa6
cdrom         esp10          esp27  esp43  esp6      fd0u1840    loop2    nvram     ram14    sda2        systty  tty22  tty39  tty55  ttyQ01e5  ttyQ02e7  ttyS1           usbdev4.1_ep00  VolGroup00
cdrom-sr0     esp11          esp28  esp44  esp60     fd0u1920    loop3    oldmem    ram15    sdb         tape    tty23  tty4   tty56  ttyQ01e6  ttyQ02e8  ttyS2           usbdev4.1_ep81  X0R
cdrw          esp12          esp29  esp45  esp61     fd0u360     loop4    par0      ram2     sdb1        tty     tty24  tty40  tty57  ttyQ01e7  ttyQ02e9  ttyS3           usbdev5.1_ep00  zero
cdrw-sr0      esp13          esp3   esp46  esp62     fd0u720     loop5    parport0  ram3     sequencer   tty0    tty25  tty41  tty58  ttyQ01e8  ttyQ02ea  ttyUSB0         usbdev5.1_ep81
cdwriter      esp14          esp30  esp47  esp63     fd0u800     loop6    parport1  ram4     sequencer2  tty1    tty26  tty42  tty59  ttyQ01e9  ttyQ02eb  urandom         vcs
cdwriter-sr0  esp15          esp31  esp48  esp64     fd0u820     loop7    parport2  ram5     sg0         tty10   tty27  tty43  tty6   ttyQ01ea  ttyQ02ec  usbdev1.1_ep00  vcs1
console       esp16          esp32  esp49  esp7      fd0u830     lp0      parport3  ram6     sg1         tty11   tty28  tty44  tty60  ttyQ01eb  ttyQ02ed  usbdev1.1_ep81  vcs2
core          esp17          esp33  esp5   esp8      floppy      MAKEDEV  port      ram7     sg2         tty12   tty29  tty45  tty61  ttyQ01ec  ttyQ02ee  usbdev1.3_ep00  vcs3
disk          esp18          esp34  esp50  esp9      floppy-fd0  mapper   ppp       ram8     sg3         tty13   tty3   tty46  tty62  ttyQ01ed  ttyQ02ef  usbdev1.3_ep02  vcs4
dsp           esp19          esp35  esp51  fd        full        md0      ptmx      ram9     shm         tty14   tty30  tty47  tty63  ttyQ01ee  ttyQ04e0  usbdev1.3_ep81  vcs5
dvd           esp2           esp36  esp52  fd0       gpmctl      mem      pts       ramdisk  snd         tty15   tty31  tty48  tty7   ttyQ01ef  ttyQ04e1  usbdev2.1_ep00  vcs6
dvdrw         esp20          esp37  esp53  fd0u1040  hpet        mixer    ram       random   st0         tty16   tty32  tty49  tty8   ttyQ02e0  ttyQ04e2  usbdev2.1_ep81  vcsa
dvdrw-sr0     esp21          esp38  esp54  fd0u1120  initctl     net      ram0      rawctl   st0a        tty17   tty33  tty5   tty9   ttyQ02e1  ttyQ04e3  usbdev2.2_ep00  vcsa1
 
Old 08-15-2016, 05:04 PM   #2
Ztcoracat
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Quote:
I am trying to find out which device is Bus 002 Device 002: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
It looks like PL2303 is a printer.

http://www.prolific.com.tw/US/ShowProduct.aspx?pcid=41

http://www.prolific.com.tw/US/ShowPr...id=225&pcid=41

Last edited by Ztcoracat; 08-15-2016 at 05:06 PM.
 
Old 08-15-2016, 05:09 PM   #3
JoseKreif
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Quote:
Originally Posted by Ztcoracat View Post
This is an old dial-up modem, I believe it's interface is a printer interface, (25 pin). I will need to go back and look at it maybe
 
Old 08-15-2016, 05:15 PM   #4
JoseKreif
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If this helps

Code:
[root@plant01 dev]# dmesg | grep tty
serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
00:10: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
usb 2-1: pl2303 converter now attached to ttyUSB0
it assigns usb 2-1 to ttyUSB0. How can I get Usb 2-2 to ttyUSB0 ?
 
Old 08-15-2016, 05:28 PM   #5
Ztcoracat
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These links might help.

http://unix.stackexchange.com/questi...ke-dev-ttyusb0
http://unix.stackexchange.com/questi...b0-on-embedded
http://stackoverflow.com/questions/5...n-ubuntu-10-10

Quote:
This is an old dial-up modem, I believe it's interface is a printer interface
You will need a member that knows how to work with that type of connection and change it to a Usb 2-2 to ttyUSB0.
Sorry I don't know how. If I find the answer I will post it for you.
 
Old 08-15-2016, 05:45 PM   #6
michaelk
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No need to do anything, the device should be usable as is. You might need to add your user to the dialout group.

What are you trying to accomplish? You can use minicom to communicate with the MODEM.
 
Old 08-15-2016, 06:23 PM   #7
Doug G
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Quote:
This is an old dial-up modem, I believe it's interface is a printer interface, (25 pin). I will need to go back and look at it maybe
25pin db25 connectors on old modems are rs232 serial connectors, not parallel printer connectors.
 
Old 08-16-2016, 07:41 AM   #8
JoseKreif
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Quote:
Originally Posted by Doug G View Post
25pin db25 connectors on old modems are rs232 serial connectors, not parallel printer connectors.
I just checked a spare modem, it has 25 pin interface.

Also found the webpage for them
http://www.usr.com/products/56k-dialup-modem/usr3453c/

EDIT

someone in the IT dept found notes from 2012 that we were going to discontinue the service for the modem. This could explain why I having trouble getting this modem working again.
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Last edited by JoseKreif; 08-16-2016 at 07:58 AM.
 
Old 08-16-2016, 07:46 AM   #9
michaelk
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A serial port can be either 9 or 25 pin. The original specification was 25 pin.

http://www.aggsoft.com/rs232-pinout-cable/RS232.htm

PL2303 is the Prolific USB serial port chipset. It is not a parallel port or printer.

Last edited by michaelk; 08-16-2016 at 07:51 AM.
 
Old 08-16-2016, 08:24 AM   #10
JoseKreif
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Quote:
Originally Posted by michaelk View Post
A serial port can be either 9 or 25 pin. The original specification was 25 pin.

http://www.aggsoft.com/rs232-pinout-cable/RS232.htm

PL2303 is the Prolific USB serial port chipset. It is not a parallel port or printer.
Well something isn't right. Because there is no printer connected to the server. We do those things wirelessly with CUPS. I assume it's picking information from the adaptor, since the server is connected to the modem using a DB25 to USB adaptor. I can't remember exactly how it was setup, but it might even have been DB25 to Serial to USB

EDIT:
from dmesg

Code:
drivers/usb/serial/pl2303.c: Prolific PL2303 USB to serial adaptor driver
usb 2-1: pl2303 converter now attached to ttyUSB0

Last edited by JoseKreif; 08-16-2016 at 08:35 AM.
 
Old 08-16-2016, 08:50 AM   #11
michaelk
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Ok, so what are you trying to accomplish?
 
Old 08-16-2016, 09:29 AM   #12
JoseKreif
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Quote:
Originally Posted by michaelk View Post
Ok, so what are you trying to accomplish?
I was trying to figure out why USB 2-1 was being assigned to ttyUSB0, when USB 2-1 has no device. The device I need is USB 2-2.

Also, I am no longer working on this issue since the modem is now out of service. dialing-in is not possible now.
 
Old 08-16-2016, 10:06 AM   #13
michaelk
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I understand...

It is what we call "Overcome By Events" (OBE)

I've used Prolific USB serial adapters with CentOS for quite awhile now and never had a problem. If you want you can mark this thread as solved via the thread tools pull down menu at the top of the page.
 
  


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