USB-DB9 serial cable requirments

Solideco
Member
 
Posts: 24
Joined: Sun Jun 12, 2016 6:08 pm
Has thanked: 3 times
Been thanked: 0 time

USB-DB9 serial cable requirments

Fri Apr 14, 2017 6:48 pm

While I probably still have some (very) old serial cables lying in a box somewhere from when Kermit and zmodem were a thing, I no longer have a computer with a DB9 port.

So its now a USB-DB9 serial cable from Amazon.

Unfortunately, and it's making me feel like a total noob, I can't get a useful terminal session to work from Linux.

I'm using minicom on Linux Mint/Debian Jesse. 8N1 and 115200.

The only time minicom shows a response from the switch is after I send a Hangup sequence. Type something, send Hangup, type some more, send another Hangup... This shows that there is some communication but it is not useful.

It's been a while but I've done enough with serial connections in the past that something seems off. And I'm pointing the finger at the serial cable as I can't get it to work when connected to a few different devices.

So, are there some USB-DB9 serial cables that work and some to avoid due to chipsets or other things?

'lsusb' displays the following for the cable in question: (The verbose output is below.)

Bus 002 Device 005: ID 0403:6001 Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC

Thanks
Mark

(grrr... the heiriarchal indenting is lost when I paste the output..)
Code: Select all
# lsusb -v -d 0403:6001
Bus 002 Device 005: ID 0403:6001 Future Technology Devices International, Ltd FT232 USB-Serial (UART) IC
Device Descriptor:
 bLength 18
 bDescriptorType 1
 bcdUSB 2.00
 bDeviceClass 0 (Defined at Interface level)
 bDeviceSubClass 0
 bDeviceProtocol 0
 bMaxPacketSize0 8
 idVendor 0x0403 Future Technology Devices International, Ltd
 idProduct 0x6001 FT232 USB-Serial (UART) IC
 bcdDevice 6.00
 iManufacturer 1 FTDI
 iProduct 2 FT232R USB UART
 iSerial 3 AK05D2XC
 bNumConfigurations 1
 Configuration Descriptor:
 bLength 9
 bDescriptorType 2
 wTotalLength 32
 bNumInterfaces 1
 bConfigurationValue 1
 iConfiguration 0
 bmAttributes 0xa0
 (Bus Powered)
 Remote Wakeup
 MaxPower 90mA
 Interface Descriptor:
 bLength 9
 bDescriptorType 4
 bInterfaceNumber 0
 bAlternateSetting 0
 bNumEndpoints 2
 bInterfaceClass 255 Vendor Specific Class
 bInterfaceSubClass 255 Vendor Specific Subclass
 bInterfaceProtocol 255 Vendor Specific Protocol
 iInterface 2 FT232R USB UART
 Endpoint Descriptor:
 bLength 7
 bDescriptorType 5
 bEndpointAddress 0x81 EP 1 IN
 bmAttributes 2
 Transfer Type Bulk
 Synch Type None
 Usage Type Data
 wMaxPacketSize 0x0040 1x 64 bytes
 bInterval 0
 Endpoint Descriptor:
 bLength 7
 bDescriptorType 5
 bEndpointAddress 0x02 EP 2 OUT
 bmAttributes 2
 Transfer Type Bulk
 Synch Type None
 Usage Type Data
 wMaxPacketSize 0x0040 1x 64 bytes
 bInterval 0
Device Status: 0x0000
 (Bus Powered)

User avatar
sirhc
Employee
Employee
 
Posts: 7347
Joined: Tue Apr 08, 2014 3:48 pm
Location: Lancaster, PA
Has thanked: 1597 times
Been thanked: 1317 times

Re: USB-DB9 serial cable requirments

Fri Apr 14, 2017 7:30 pm

Are you sure your using a NULL serial cable?
Support is handled on the Forums not in Emails and PMs.
Before you ask a question use the Search function to see it has been answered before.
To do an Advanced Search click the magnifying glass in the Search Box.
To upload pictures click the Upload attachment link below the BLUE SUBMIT BUTTON.

Solideco
Member
 
Posts: 24
Joined: Sun Jun 12, 2016 6:08 pm
Has thanked: 3 times
Been thanked: 0 time

Re: USB-DB9 serial cable requirments

Fri Apr 14, 2017 7:37 pm

It is one of the USB-DB9 serial cables with a FTDI Chipset.

See: https://www.amazon.com/gp/product/B01GA0IZBO/

User avatar
jakematic
Experienced Member
 
Posts: 168
Joined: Thu Jul 14, 2016 8:15 am
Location: NC USA
Has thanked: 362 times
Been thanked: 87 times

Re: USB-DB9 serial cable requirments

Sat Apr 15, 2017 9:15 am

First thing I would do is check your flow control settings in minicom if it's acting like that.
It also may not be an actual null model setup - could just be the correct gender

Used to always use FTDI but in recent years have had some problems in Linux so switched to these using a null modem cable: https://www.bhphotovideo.com/c/product/ ... erial.html

I know they work on Ubuntu, and seem to remember using them on Raspbian Jessie as well.


Edit: Bus 001 Device 003: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port

Solideco
Member
 
Posts: 24
Joined: Sun Jun 12, 2016 6:08 pm
Has thanked: 3 times
Been thanked: 0 time

Re: USB-DB9 serial cable requirments

Sat Apr 15, 2017 9:29 am

Perfect!

Just what I was looking for, a cable that is known to work. Thanks!

Return to General Discussion

Who is online

Users browsing this forum: No registered users and 22 guests