tipi di protocollo informatico, tipi di protocollo di comunicazione informatico.
Controller/peripheral formerly known as master/slave
Arduino no longer supports the use of master/slave terminology.
ref: https://docs.arduino.cc/learn/communication/one-wire
one speaks, all listen
any information
sent by one station is received by all
even if that information is intended for
just one destination.
slave speak-when-spoken-to
slave communicates only when the master requests it;
i.e. not
allowed slave-initiated communications.
single-drop system 1 slave on the bus
multidrop
more slaves on the bus.
simplex communication 1 device transmits, the others can
only listen.
Examples: broadcast radio and television, garage door openers, baby monitors,
wireless microphones, and surveillance cameras.
duplex communication devices that can communicate with one another in both directions
FDX full-duplex trasmissione bidirezionale simultanea
HDX half-duplex trasmissione bidirezionale alternata
2 ways alternate il canale e' bidirezionale, ma viene usato solo in una direzione per volta.
Some computer-based systems of the 1960s and 1970s required full-duplex facilities, even for half-duplex operation, since their poll-and-response schemes could not tolerate the slight delays in reversing the direction of transmission in a half-duplex line.
in una rxtx (ricetrasmissione)
ACK / NAK affirmative/negative response, transmitted from a receiver as a response to the sender.
Un messaggio inviato a seguito della ricezione di un messaggio per accettarlo o rifiutarlo. es:
Many protocols contain checksums to verify the integrity of the payload and header.
Nel codice ASCII: 06H ACK 15H NAK
https://www.aivosto.com/articles/control-characters.html