On Fri, 26 Jun 2020 11:15:35 +0200, "R.Wieser" 
declaimed the following:

>I just realized I should take a peek at USB-to-RS232 converters.  Those
>might well have a much higher thruput than what the UART offers.

 Not really...

 The key is that the A is for "asynchronous"... Each byte is sent as a
discrete entity -- in 8n1 configuration, each 8 bit byte is sent as a 10
bit entity (start bit, 8 data bits, stop bit) [If you use parity with 8
data bits, you'll end up sending 11 bits total].

 Ethernet is a synchronous system... there are a few bytes for
synchronizing, but then the entire information packet gets sent without the
start/stop bits between bytes. True, there is some overhead for IP/port
information, and over that for the MAC address information. Also, the
packets have a checksum for error detection.

 At one time, one could find USART chips, which could handle
asynchronous or synchronous transmissions (but in those days, a high-speed
USART was around 38400 bps  ).


 If you have an R-Pi 3B+ and a WiFi router you may already have a test
case you can perform... Use a CAT-5/CAT-6 cable from the R-Pi to one of
your separated networks, and configure the R-Pi WiFi to connect to the
other network with the WiFi router. Then try SSH connections from each
network to the R-Pi.


--
 Wulfraed                 Dennis Lee Bieber         AF6VN
 wlfraed@ix.netcom.com    http://wlfraed.microdiversity.freeddns.org/

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