Hello,
I have a simple web server running on STM23F7. I can control LEDs via Ethernet and display sensor values on the web. The question is how to achieve automatic refresh of data from the sensor. Using HTML, I can refresh the whole page every 1 second, but I don't know how to update only the value without refreshing the whole site.
Thank you
Here is the STM code:
#define numSSItags 4
bool LD1ON = false; // this variable will indicate if the LD3 LED on the board is ON or not
bool LD2ON = false; // this variable will indicate if our LD2 LED on the board is ON or not
extern float AHT10_Temperature;
extern float AHT10_Humidity;
tCGI theCGItable[1];
char const *theSSItags[numSSItags] = { "tag1", "tag2" , "tag3" , "tag4" }; //definice tagu
const char* LedCGIhandler(int iIndex, int iNumParams, char *pcParam[], char *pcValue[]) {
uint32_t i = 0;
if (iIndex == 0) { //turning the LED lights off
//turning the LED lights off
HAL_GPIO_WritePin(LD2_GPIO_Port, LD2_Pin, GPIO_PIN_RESET);
// we put this variable to false to indicate that the LD2 LED on the board is not ON
LD2ON = false;
HAL_GPIO_WritePin(LD3_GPIO_Port, LD3_Pin, GPIO_PIN_RESET);
// we put this variable to false to indicate that the LD* LED on the board is not ON
LD1ON = false;
}
for (i = 0; i < iNumParams; i++) {
if (strcmp(pcParam[i], "led") == 0){
if (strcmp(pcValue[i], "1") == 0) {
HAL_GPIO_WritePin(LD3_GPIO_Port, LD3_Pin, GPIO_PIN_SET);
LD1ON = true; // LD3 LED (red) on the board is ON!
}
else if (strcmp(pcValue[i], "2") == 0) {
HAL_GPIO_WritePin(LD2_GPIO_Port, LD2_Pin, GPIO_PIN_SET);
LD2ON = true; // LD2 LED (blue) on the board is ON!
}
}
}
// the extension .shtml for SSI to work
return "/index.shtml";
} // END [= CGI #5 =]
const tCGI LedCGI = { "/leds.cgi", LedCGIhandler }; // in our SHTML file <form method="get" action="/leds.cgi">
// function to initialize CGI [= CGI #6 =]
void myCGIinit(void) {
//add LED control CGI to the table
theCGItable[0] = LedCGI;
//give the table to the HTTP server
http_set_cgi_handlers(theCGItable, 1);
} // END [= CGI #6 =]
// the actual function for SSI [* SSI #4 *]
u16_t mySSIHandler(int iIndex, char *pcInsert, int iInsertLen) {
if (iIndex == 0) {
if (LD1ON == false) {
char myStr1[] = "<input value=\"1\" name=\"led\" type=\"checkbox\">";
strcpy(pcInsert, myStr1);
return strlen(myStr1);
}
else if (LD1ON == true) {
// since the LD3 red LED on the board is ON we make its checkbox checked!
char myStr1[] = "<input value=\"1\" name=\"led\" type=\"checkbox\" checked>";
strcpy(pcInsert, myStr1);
return strlen(myStr1);
}
}
else if (iIndex == 1) {
if (LD2ON == false) {
char myStr2[] = "<input value=\"2\" name=\"led\" type=\"checkbox\">";
strcpy(pcInsert, myStr2);
return strlen(myStr2);
} else if (LD2ON == true) {
// since the LD2 blue LED on the board is ON we make its checkbox checked!
char myStr2[] = "<input value=\"2\" name=\"led\" type=\"checkbox\" checked>";
strcpy(pcInsert, myStr2);
return strlen(myStr2);
}
}
else if (iIndex == 2) {
char myStr3[5];
gcvt (AHT10_Temperature, 4, myStr3);
strcpy(pcInsert, myStr3);
return strlen(myStr3);
}
else if (iIndex == 3) {
char myStr4[5];
gcvt (AHT10_Humidity, 4, myStr4);
strcpy(pcInsert, myStr4);
return strlen(myStr4);
}
return 0;
}
// function to initialize SSI [* SSI #5 *]
void mySSIinit(void) {
http_set_ssi_handler(mySSIHandler, (char const**) theSSItags, numSSItags);
}
