glen.slick at gmail.com
Fri Jun 25 18:54:07 CDT 2021
On Fri, Jun 25, 2021 at 3:53 PM Grant Taylor via cctalk
<cctalk at classiccmp.org> wrote:
> From my naive point of view, I wonder if it would be possible to build
> some sort of USB device that has a traditional UART that has supporting
> circuitry to connect to the host over USB. -- I say this because it
> sounds like many ~> most ~> all (?) USB to RS-232 converters are doing
> something inferior.
Of course that has been done in commercial products. For example I
have some Inside Out Networks Edgeport / 4 devices (apparently later
sold by Digi) that are implemented using a traditional ST16C654 quad
UART and MAX3243E RS-232 transceivers, with an Intel 80930
microcontroller as the interface between the UART and the USB host.
The Intel 80930 has an 80251 core integrated with a USB interface, and
was one of the first microcontrollers available on the market. This
device dates from 1997, so reasonably early in the USB game.
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