PROTOCOL(3spp)      RISC/os Reference Manual       PROTOCOL(3spp)



NAME
     protocol - serial line protocol routines

SYNOPSIS
     #include <saio/protocol.h>
     #include <saio/protoio.h>

     void init_proto(fd)
     pdev_t fd;

     void proto_enable(fd)
     pdev_t fd;

     void proto_disable(fd)
     pdev_t fd;

     int getpkt(fd, buf, cnt, pkt_typep)
     pdev_t fd;
     char *buf;
     unsigned cnt;
     int *pkt_typep;

     void putpkt(fd, buf, cnt, pkt_type)
     pdev_t fd;
     char *buf;
     unsigned cnt;
     int pkt_type;

DESCRIPTION
     These routines implement the serial line protocol used by
     the debug monitor dbgmon(1spp), for remote debugging mode
     and the PROM monitor download command load(1spp).

     Init_proto must be called to initiate the protocol sequence
     counters before any other protocol routines are invoked.  It
     should be invoked each time a protocol connection is
     attempted.  The argument fd should be the file descriptor
     for the serial port that will be used for communication.

     Proto_enable must be called to configure the serial port
     indicated by fd for use by the protocol routines.
     Proto_enable puts the line in "raw" mode and flushes any
     pending input and output on the serial port.  Fd should be
     the file descriptor for the the serial port that will be
     used for communication.

     Proto_disable should be called after the protocol session is
     complete to restore the line to "cooked" mode.  Fd should be
     the file descriptor for the the serial port that was used
     for communication.





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PROTOCOL(3spp)      RISC/os Reference Manual       PROTOCOL(3spp)



     Getpkt blocks until it receives a properly sequenced and
     checksummed packet on the serial line indicated by fd.  The
     packet will be returned in the buffer pointed to by buf.
     The buffer is assumed to be cnt bytes long.  If the received
     packet is longer than cnt bytes it is discarded.  pkt_typep
     is a pointer to a integer variable that should be initial-
     ized to DATA_PKTTYPE.  Other values for pkt_typep are used
     internally by the protocol code.  Getpkt acknowledges the
     reception of the packet to its remote partner and returns
     the length of the packet.

     Putpkt transmits a packet on the file descriptor fd and
     waits until the packet is acknowledged by its remote
     partner.  Putpkt will periodically retransmit the packet
     until the packet is acknowledged.  The packet to be
     transmitted should be pointed to by the character pointer
     buf and be of length cnt bytes.  Pkt_type should be
     DATA_PKTTYPE.

     This code can, with reasonable effort, be incorporated into
     host system programs to act as the remote partner for the
     standalone code utilizing the protocol.  In order to accom-
     plish this the macros defined in protoio.h must be altered
     to fit the host environment and timer support along the
     lines of set_timer(3spp) must be provided.

SEE ALSO
     protocol(5spp)



























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