Files
sicspsi/phytron.c
koennecke 8162f117bd - Introduced a new trace facility
- Fixed performance problems in many protocol drivers.
2011-06-29 07:53:54 +00:00

102 lines
2.3 KiB
C

/**
* This is an asynchronous protocol driver for the protocol of
* the Phytron MCC-2 motor controller.
* The send format is:
* <STX> DATA <ETX>
* the reply format is:
* <STX> NACK | ACK |& REPLY <ETX>
*
* copyright: see file COPYRIGHT
*
* Mark Koennecke, June 2009
*/
#include <errno.h>
#include <ascon.h>
#include <ascon.i>
#include <dynstring.h>
#define STX '\2'
#define ETX '\3'
#define NACK '\5'
#define ACK '\6'
/*---------------------------------------------------------------------------*/
static int PhytronHandler(Ascon * a)
{
char *data = NULL;
int ret, l;
char chr;
switch (a->state) {
case AsconWriteStart:
DynStringInsert(a->wrBuffer,"\2",0);
DynStringConcatChar(a->wrBuffer,ETX);
a->state = AsconWriting;
a->wrPos = 0;
break;
case AsconReading:
ret = AsconReadChar(a->fd, &chr);
if (ret < 0) {
/* EINTR means we must retry */
if (errno != EINTR && errno != EAGAIN) {
AsconError(a, "AsconReadChar failed:", errno);
}
return 1;
} else if (ret > 0) {
if(chr == STX){
DynStringClear(a->rdBuffer);
} else if (chr == ACK){
DynStringConcat(a->rdBuffer,"ACK");
} else if(chr == NACK){
DynStringConcat(a->rdBuffer,"NACK");
} else if(chr == ETX){
a->state = AsconReadDone;
} else {
DynStringConcatChar(a->rdBuffer,chr);
}
} else if (ret == 0) {
if (a->timeout > 0) {
if (DoubleTime() - a->start > a->timeout) {
AsconError(a, "read timeout", 0);
a->state = AsconTimeout;
}
}
return 0;
}
break;
default:
return AsconStdHandler(a);
}
return 1;
}
/*------------------------------------------------------------------------*/
static int PhytronInit(Ascon * a, SConnection * con, int argc, char *argv[])
{
a->fd = -1;
a->state = AsconConnectStart;
a->reconnectInterval = 10;
a->hostport = strdup(argv[1]);
if (argc > 2) {
a->timeout = atof(argv[2]);
} else {
a->timeout = 2.0; /* sec */
}
a->killPrivate = free;
return 1;
}
/*------------------------------------------------------------------------*/
void AddPhytronProtocoll()
{
AsconProtocol *prot = NULL;
prot = calloc(sizeof(AsconProtocol), 1);
prot->name = strdup("phytron");
prot->init = PhytronInit;
prot->handler = PhytronHandler;
AsconInsertProtocol(prot);
}