nanog mailing list archives
Re: Devices with only USB console port - Need a Console Server Solution
From: Keenan Tims <ktims () stargate ca>
Date: Tue, 2 Feb 2016 12:06:38 -0800
On 2016-02-02 02:02, Bjørn Mork wrote:
As you are probably aware, there are no standard USB-DB9 Console adapters. They are all vendor specific. But the cloning industry has created a few semi-standards based on specific chipsets.
This is not strictly true. There is a Communications Device Class (CDC ACM) defined by the USB-IF that covers basic serial devices and most OSs (even Windows! Though it does require a .inf file anyway) include a driver for it. A rumour I heard recently was that its lack of popularity was a result of Microsoft and Intel not wanting device developers to ignore the advantages of USB and just use CDC to continue using their old-school RS232 protocols for mice or whatever. There are also some good reasons not to use it, such as flow control, strict timing, higher data rates, and added features available with custom chipsets, but it's just fine for a serial console. Exar, Microchip and others make simple and cheap USB-UART chips using CDC ACM, and it's a very common application example for USB microcontrollers. USB console ports are just adding complexity where it offers no advantage. KISS. Keenan
Current thread:
- RE: Devices with only USB console port - Need a Console Server Solution Erik Sundberg (Feb 01)
- Re: Devices with only USB console port - Need a Console Server Solution Christopher Morrow (Feb 01)
- Re: Devices with only USB console port - Need a Console Server Solution Bjørn Mork (Feb 02)
- RE: Devices with only USB console port - Need a Console Server Solution Erik Sundberg (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Bjørn Mork (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Bjørn Mork (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Keenan Tims (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Robert Drake (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Dovid Bender (Feb 02)
- RE: Devices with only USB console port - Need a Console Server Solution Erik Sundberg (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Christopher Morrow (Feb 03)
- Re: Devices with only USB console port - Need a Console Server Solution Miles Fidelman (Feb 03)
- Re: Devices with only USB console port - Need a Console Server Solution Christopher Morrow (Feb 01)
- <Possible follow-ups>
- Re: Devices with only USB console port - Need a Console Server Solution Jared Mauch (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Peter Loron (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Christopher Morrow (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution William Herrin (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Jared Mauch (Feb 02)
- Re: Devices with only USB console port - Need a Console Server Solution Peter Loron (Feb 02)