do a bit of effort and take into account what was discussed in the other posts please or I'll have to agree with the others that you are trolling and not listening...
post a complete code that you can compile. (a minimum example)
though we had discussed that RSSI would be better as numbers than text?
thought we said typedef is useless ?
char dID1 = myDatatable[0].dID; //error occurs from here until hops there..
in your code, what is the type of dIDin the struct ?
what's the type of dID1 when trying to do the assignment that fails ?
if ((myDatatable[i].pRSSI<=min_pRSSI))
there is no pRSSI value in the struct, we have no clue what min_pRSSI is...
long story short, please provide a fully self contained working example.
struct {
char messageType[2];
char sID[3] = {0} ; // key1
char dID[3];
char routes1[3];
char routes2[3]; //key2
int16_t RSSI1[5];
int16_t RSSI2[5];
int16_t pRSSI[5];
char hops[2];
} MyDataSet_t ;
MyDataSet_t myDatatable[MAX_SENDERS] ; //correction: max_senders should be assigned as 5
char dID1[3] = myDatatable[0].dID;
char routes1[3]= myDatatable[0].routes1;
char routes2[3] = myDatatable[0].routes2;
char min_RSSI1[5] = myDatatable[0].RSSI1; // how do I assign to the array[0] then if they are changed to int16_t?
char min_RSSI2[5] = myDatatable[0].RSSI2;
char min_pRSSI[5] = myDatatable[0].pRSSI; // are the addition of RSSI1 and RSSI2
char min_hops[2] = myDatatable[0].hops;
void dispaly() {
for ( uint16_t i = 0 ; i < MAX_SENDERS ; i++ ) {
sprintf( buf , "%s %s %s %s %s %s \n" ,
myDatatable[ i ].messageType ,
myDatatable[ i ].sID ,
myDatatable[ i ].dID ,
myDatatable[ i ].routes1 ,
myDatatable[ i ].hops,
myDatatable[ i ].pRSSI
);
Serial.print( buf ) ;
snprintf(myDatatable[i].pRSSI , 5 , "%i" , pRSSI);
if ((myDatatable[i].pRSSI<=min_pRSSI)) //comparison starts here
{
min_pRSSI = myDatatable[i].pRSSI;
dID1 = myDatatable[i].dID;
min_hops = myDatatable[i].hops;
routes1 = myDatatable[i].routes1; // they are to be used to send data back later
routes2 = myDatatable[i].routes2;
}
}
}
because the message.messageType in your code is kind of confusing for me.. and I didn't think the post can be continued discussing anymore..so I thought of using this instead.. and I tried to convert it back to integer to add them up before converting them back into string using snprintf.. but ya.. it is not as easy as expected.. so for the message.messageType way you using, is directly assigning the data into the struct, am I correct? then do you mind to share how do I look back the table and do the comparison as above, which I attempt to do..?
and for only pRSSI will be used to compared with each other , and the particular line will be chosen to be used later on, which I am not showing the code here(I guess I am able to do this), that's why I only use pRSSI to compare, then just assign other variable with the variables in the particular line..
sizeof is an operator returning the number of bytes used to represent a type or a variable
So
sizeof myDatatable is the number of bytes used to represent the full array of structures
sizeof myDatatable[0] is the number of bytes used to represent the first entry
so if you divide the total size of the array by the size of one element of the array (they all have the same size) you get the number of entries in the array ➜ databaseCount will be 6
that should work unless there is something I don't see because it's a snippet...
Anyway, because you have struct, you can do
MyDataSet_t tmpData = myDatatable[0];
then everything is copied in one go, you duplicated myDatatable[0]into tmpData (this works on struct, it does not work on arrays. but if the array is within the struct then it's OK, as any other simple datatype)
that's how I did for all, so should be the same for other variables...
so my code should be
MyDataSet_t tmpData = myDatatable[0];
char min_RSSI[5];
strcpy(min_RSSI,tmpData.RSSI);
//or strlcpy version:
strlcpy(min_RSSI,tmpData.RSSI, sizeof min_RSSI);
//adding up
for ( uint16_t i = 0 ; i < MAX_SENDERS ; i++ ) {
sprintf( buf , "%s %s %s %s %s %s \n" ,
myDatatable[ i ].messageType ,
myDatatable[ i ].sID ,
myDatatable[ i ].dID ,
myDatatable[ i ].routes1 ,
myDatatable[ i ].hops,
myDatatable[ i ].RSSI
);
Serial.print( buf ) ;
snprintf(myDatatable[i].RSSI , 5 , "%i" , RSSI);
if ((myDatatable[i].RSSI<=min_RSSI)) //comparison starts here
{
min_pRSSI = myDatatable[i].pRSSI;
dID1 = myDatatable[i].dID; //assuming they are assigned like min_RSSI
min_hops = myDatatable[i].hops;
routes1 = myDatatable[i].routes1; // they are to be used to send data back later
routes2 = myDatatable[i].routes2;
}
}
}
that would work. But do you need min_RSSI? can't you just use tmpData to hold the min and the rest of the structure?
Best probably would be to study my sample code rather than keep on with you memory costly idea....
You can see I did not duplicate any structure, I just identified the Index of the structure holding the min value.
That's how you should proceed.
once you have identified the location of the min struct, if you want to duplicate it into a variable, just do the struct assignment.
I am sorry, I am NO LONGER looking at code I can't compile.
As said now multiple times. when you want to do something put the big code away and create a small example you can focus on outside the rest of the code.
Once you've solved your problem in the small example, you apply that to your real code.
it's past bed time here, so I let you understand the code with just one piece of advice that we already discussed:
➜ You can't compare strings... if ((myDatatable[i].RSSI<=min_RSSI))is wrong, you compare numbers... (remember strtol() please ? I spent enough time explaining it...)
