On Sat, 15 Feb 2020 20:38:00 -0000 (UTC), Martin Gregorie
 declaimed the following:


>However, you should definitely take note of Dennis's comment about bulk,
>and consider whether you'd be better using a Pi Zero, or one of the small
>Arduinos, rather than a bigger and much thicker Pi with its bank of

 Problem with the Arduino route (I considered mentioning them but
refrained) is that they don't run a formal OS in which programs are loaded
from a file system. The versions using an ARM Cortex-M processor (Due, for
example) can usually support FreeRTOS if one needs interrupt handling or
multiple threads of execution, but they still expect to boot directly to
/the/ application which runs from flash memory -- RAM is basically a very
large "register set" only used for variable storage during execution. The
Cortex-A of R-Pi and BeagleBone Black both use flash for a file system and
load programs into RAM for execution

   The Due is 84MHz Cortex M3 (no floating point), 512kB flash, 96kB RAM
(in banks of 64 and 32kB).

 A TIVA TM4C123G LaunchPad (since the specs are on the box I have
available -- the Due specs I have to Google) is an 80MHz Cortex M4F (32-bit
with hardware floating point), 256kB flash, 32kB SRAM, 2kB EEPROM. One
thing it is unusual in is that it has way too many timers (6 64-bit, which
can be split into 12 32-bit, AND 6 32-bit which can split into 12 16-bit
). But it is cheap (presuming TI still makes them -- about $13).

 The larger TM4C1294 is 120MHz M4F, 1MB flash, 256kB SRAM, 6kB EEPROM,
only 8 32-bit timers, but has Ethernet connector [your application will
need to include a TCP/IP stack to use it].



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

--- SoupGate-Win32 v1.05