Serial RX/TX from the Arduino at 5v

i think called rs485, not sure.

i working on project , there device spitting out 1200 baud (8n1) , goes arduino.
there "looked at" , actioned needed.

thing is, don't know how can , flash arduino new software if doesn't work while still in situe/place.   (spelling?)

i not sure sent.   (at 5v signal levels)

so isn't can have serialmonitor open well.

i have heard of beast ftdi, know nothing of it.   other way program arduino.

i shall go , try learn too, looking pointers people may have been here before.

it tricky because:
as 5v levels, can't watch data pc.  , arduino has 1 (?) comm port, , if receiving data other device, can't report pc seeing.

the "cheat" way around (kinda) read 'n' characters end , read them backwards, sort of thing.

that way, "header" of don't know negated, important stuff (the last 8 characters) .....  last 8 characters.

read in string (?term?) , @ right-most 8 , use them.

do-able?

(oh, don't e-mails of responses, if reply , weeks before reply you:  not being rude.  not getting e-mails sent me.)

i shall try keep eye here, have 30 tabs open doing other sites , gets annoying when want go online , @ , have wait while other 30 pages load.
(that's on day)   it has been .....  80 tabs think @ 1 stage.

yuck!

when log in @ forum, there link "updated topics" in upper-right of screen. shows new replies topics.

first of all, have more information device , serial communication ?
it connected arduino ?
that means rx , tx ttl 5v levels ?

saleae (www.saleae.com) has logic analyzers software decodes pulses of data, show serial data.

do have arduino leonardo/micro or arduino mega ? have spare hardware serial port.
with arduino mega 2560 can connect 2 spare serial inputs both rx , tx of device, , listen both rx , tx.

Arduino Forum > Using Arduino > Networking, Protocols, and Devices (Moderator: fabioc84) > Serial RX/TX from the Arduino at 5v

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