working fft api, various improvements in sampling, added sampling stats..

esp_meas.pro.user

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE QtCreatorProject>
-<!-- Written by QtCreator 3.6.1, 2016-03-29T02:35:32. -->
+<!-- Written by QtCreator 3.6.1, 2016-03-29T21:45:36. -->
 <qtcreator>
  <data>
   <variable>EnvironmentId</variable>

html/json/samples.tpl

@@ -1,4 +1,5 @@
 {
   "samples": [%values%],
+  "stats": %stats%,
   "success": %success%
 }

html_src/js-src/lib/chartist.js

@@ -1447,7 +1447,7 @@ var Chartist = {
               ys[i + 1],
 
               false,
-              valueData[i]
+              valueData[i + 1] // changed as per patch on github
           );
         }
 

html_src/js-src/page_waveform.js

@@ -87,7 +87,7 @@ var page_waveform = (function () {
 			return;
 		}
 
-		buildChart(json.samples, 'Sample Nr.', 'ADC value');
+		buildChart(json.samples, 'Sample number', 'Current - mA');
 	}
 
 	wfm.init = function() {
@@ -101,7 +101,7 @@ var page_waveform = (function () {
 			var freq = $('#freq').val();
 
 			//http://192.168.1.13
-			$().get('http://192.168.1.13/api/raw.json?n='+samples+'&fs='+freq, onRxData, true, true);
+			$().get('/api/raw.json?n='+samples+'&fs='+freq, onRxData, true, true);
 		}
 
 		$('#load').on('click', clickHdl);

libesphttpd/util/cgiwifi.c

@@ -254,7 +254,7 @@ int ICACHE_FLASH_ATTR cgiWiFiSetMode(HttpdConnData *connData) {
 		info("cgiWifiSetMode: %s", buff);
 #ifndef DEMO_MODE
 		wifi_set_opmode(atoi(buff));
-		system_restart();
+		system_restart(); // FIXME we should do this in a timer task, so the browser gets a response.
 #endif
 	}
 	httpdRedirect(connData, "/wifi");

user/datalink.h

@@ -5,7 +5,8 @@
 #include <sbmp.h>
 
 // request to capture data...
-#define DG_REQUEST_CAPTURE 40
+#define DG_REQUEST_RAW 40
+#define DG_REQUEST_FFT 41
 
 
 extern SBMP_Endpoint *dlnk_ep;

user/ftoa.c

@@ -1,7 +1,7 @@
 #include <esp8266.h>
 
 /* reverse:  reverse string s in place */
-static void str_reverse(char *s)
+static FLASH_FN void str_reverse(char *s)
 {
 	for (int i = 0, j = (int)(strlen(s) - 1); i < j; i++, j--) {
 		char c = s[i];
@@ -11,7 +11,7 @@ static void str_reverse(char *s)
 }
 
 /* itoa:  convert n to characters in s. returns length */
-int my_itoa(int n, char *s)
+int FLASH_FN my_itoa(int n, char *s)
 {
 	int i, sign;
 
@@ -30,7 +30,7 @@ int my_itoa(int n, char *s)
 	return i;
 }
 
-int my_ftoa(char *buffer, float f, int precision)
+int FLASH_FN my_ftoa(char *buffer, float f, int precision)
 {
 	// add 0.5 * 10^-precision
 	float rounder = 0.5;

user/page_waveform.c

@@ -2,6 +2,7 @@
 #include <httpd.h>
 #include "page_waveform.h"
 
+#include "ftoa.h"
 #include "sampling.h"
 #include "serial.h"
 #include "payload_parser.h"
@@ -17,9 +18,24 @@ typedef struct {
 } tplReadSamplesJSON_state;
 
 
+static int FLASH_FN tplSamplesJSON(MEAS_FORMAT fmt, HttpdConnData *connData, char *token, void **arg);
+
+
 int FLASH_FN tplWaveformJSON(HttpdConnData *connData, char *token, void **arg)
 {
-	char buff20[20];
+	return tplSamplesJSON(RAW, connData, token, arg);
+}
+
+
+int FLASH_FN tplFourierJSON(HttpdConnData *connData, char *token, void **arg)
+{
+	return tplSamplesJSON(FFT, connData, token, arg);
+}
+
+
+static int FLASH_FN tplSamplesJSON(MEAS_FORMAT fmt, HttpdConnData *connData, char *token, void **arg)
+{
+	char buff[128];
 	int len;
 
 	tplReadSamplesJSON_state *st = *arg;
@@ -37,53 +53,59 @@ int FLASH_FN tplWaveformJSON(HttpdConnData *connData, char *token, void **arg)
 
 		// check how many samples are requested
 		uint16_t count = 1;
-		len = httpdFindArg(connData->getArgs, "n", buff20, sizeof(buff20));
+		len = httpdFindArg(connData->getArgs, "n", buff, sizeof(buff));
-		if (len != -1) count = (uint16_t)atoi(buff20);
+		if (len != -1) count = (uint16_t)atoi(buff);
-		if (count > 4096) {
+		if (count == 0) {
-			warn("Requested %d samples, capping at 4096.", count);
+			error("Count == 0");
-			count = 4096;
+			st->success = false;
+			return HTTPD_CGI_DONE;
 		}
 
-		uint32_t freq = 4096;
+		uint32_t freq = 0;
-		len = httpdFindArg(connData->getArgs, "fs", buff20, sizeof(buff20));
+		len = httpdFindArg(connData->getArgs, "fs", buff, sizeof(buff));
-		if (len != -1) freq = (uint32_t)atoi(buff20);
+		if (len != -1) freq = (uint32_t)atoi(buff);
-		if (freq > 5000000) {
-			warn("Requested fs %d Hz, capping at 5 MHz.", freq);
-			freq = 5000000;
-		}
 		if (freq == 0) {
-			error("Requested fs 0 Hz, using 1 Hz");
+			error("Freq == 0");
-			freq = 1;
+			st->success = false;
+			return HTTPD_CGI_DONE;
 		}
 
 		st->total_count = count;
 		st->done_count = 0;
-		st->success = true; // success true by default
 
-		// REQUEST THE DATA
+		// --- REQUEST THE DATA ---
-		meas_request_data(count, freq);
+		// This actually asks the STM32 over SBMP to start the ADC DMA,
+		// and we'll wait for the data to arrive.
+		st->success = meas_request_data(fmt, count, freq);
+		if (!st->success) {
+			error("Failed to start sampling");
+		}
 	}
 
 	// the "success" field is after the data,
 	// so if readout fails, success can be set to false.
 
 	if (strcmp(token, "values") == 0) {
+		if (!st->success) {
+			// failed to start sampling
+			return HTTPD_CGI_DONE;
+		}
 
 		// Wait for a chunk
 
 		uint8_t *chunk = NULL;
 		uint16_t chunk_len = 0;
 
-		// 5 secs or 500 ms
+		// 10 secs or 100 ms - longer wait for intial data.
-		for (int i = 0; i < (st->done_count == 0 ? 5000*100: 500*100); i++) {
+		for (int i = 0; i < (st->done_count == 0 ? SAMPLING_TMEO*100: SAMP_READOUT_TMEO*100); i++) {
 			uart_poll();
-			if (meas_chunk_ready()) break;
+			if (meas_chunk_ready() || meas_is_closed()) break; // We have some data! --- or transaction aborted by peer :(
 			os_delay_us(10); // 1 ms
-			system_soft_wdt_feed();
+			system_soft_wdt_feed(); // Feed the dog, or it'll bite.
 		}
 		chunk = meas_get_chunk(&chunk_len);
 
-		if (!chunk) {
+		if (chunk == NULL) {
 			// abort, proceed to the next field.
 			meas_close();
 			st->success = false;
@@ -99,15 +121,13 @@ int FLASH_FN tplWaveformJSON(HttpdConnData *connData, char *token, void **arg)
 				httpdSend(connData, ", ", 2);
 			}
 
-			uint32_t samp = pp_u32(&pp);
+			float samp = pp_float(&pp);
-
+			my_ftoa(buff, samp, 3);
-			// print the number
+			httpdSend(connData, buff, -1);
-			os_sprintf(buff20, "%d", samp);
-			httpdSend(connData, buff20, -1);
 		}
 
-		// wait for more in this substitution
+		// wait for more data in this % tag
-		if (st->done_count < st->total_count) {
+		if (!meas_is_last_chunk()) {
 			meas_request_next_chunk();
 			return HTTPD_CGI_MORE; // more numbers to come
 		} else {
@@ -116,6 +136,46 @@ int FLASH_FN tplWaveformJSON(HttpdConnData *connData, char *token, void **arg)
 			return HTTPD_CGI_DONE;
 		}
 
+	} else if (strcmp(token, "stats") == 0) {
+
+		// the STATS json block
+		if (!st->success) {
+			httpdSend(connData, "null", 4);
+		} else {
+			// no %f in sprintf :(
+
+			MeasStats *stats = meas_get_stats();
+			httpdSend(connData, "{", 1);
+
+			sprintf(buff, "\"count\": %d, ", stats->count);
+			httpdSend(connData, buff, -1);
+
+			httpdSend(connData, "\"freq\": ", -1);
+			my_ftoa(buff, stats->freq, 3);
+			httpdSend(connData, buff, -1);
+
+			httpdSend(connData, ", \"min\": ", -1);
+			my_ftoa(buff, stats->min, 3);
+			httpdSend(connData, buff, -1);
+
+			httpdSend(connData, ", \"max\": ", -1);
+			my_ftoa(buff, stats->max, 3);
+			httpdSend(connData, buff, -1);
+
+			httpdSend(connData, ", \"rms\": ", -1);
+			my_ftoa(buff, stats->rms, 3);
+			httpdSend(connData, buff, -1);
+
+			if (fmt == FFT) {
+				// ... maybe something special for fft ...
+			}
+
+			sprintf(buff, ", \"format\": \"%s\"", fmt == RAW ? "RAW" : fmt == FFT ? "FFT" : "UNKNOWN");
+			httpdSend(connData, buff, -1);
+
+			httpdSend(connData, "}", 1);
+		}
+
 	} else if (strcmp(token, "success") == 0) {
 		// success status
 		httpdSend(connData, (st->success ? "true" : "false"), -1);

user/page_waveform.h

@@ -5,4 +5,6 @@
 
 int tplWaveformJSON(HttpdConnData *connData, char *token, void **arg);
 
+int tplFourierJSON(HttpdConnData *connData, char *token, void **arg);
+
 #endif // PAGE_WAVEFORM_H

user/routes.c

@@ -42,11 +42,14 @@ HttpdBuiltInUrl builtInUrls[] = {
 	// System Status page
 	ROUTE_TPL_FILE("/",        tplSystemStatus, "/pages/status.tpl"),
 	ROUTE_TPL_FILE("/status",  tplSystemStatus, "/pages/status.tpl"),
+
 	ROUTE_TPL_FILE("/api/status.json", tplSystemStatus, "/json/status.tpl"),
 
 	// Waveform page
 	ROUTE_FILE("/waveform", "/pages/waveform.html"), // static file, html -> can use gzip
+
 	ROUTE_TPL_FILE("/api/raw.json", tplWaveformJSON, "/json/samples.tpl"),
+	ROUTE_TPL_FILE("/api/fft.json", tplFourierJSON, "/json/samples.tpl"),
 
 	// --- WiFi config ---
 

user/sampling.c

@@ -11,25 +11,33 @@
 // the FIFO has 128 bytes, and should accomodate ideally the whole frame.
 #define CHUNK_LEN 100
 
-#define SAMPLING_TMEO 10000
-#define READOUT_TMEO 100
-
 // Only one readout can happen at a time.
 
 static struct {
-	bool pending;                       /*!< Flag that data is currently being read */
+	bool pending;      /*!< Flag that data is currently being read */
-	uint16_t sesn;                      /*!< SBMP session of the readout sequence */
+	uint16_t sesn;     /*!< SBMP session of the readout sequence */
-	bool chunk_ready;                   /*!< Chunk was received and is ready for reading */
+	bool chunk_ready;  /*!< Chunk was received and is ready for reading */
 	uint8_t received_chunk[CHUNK_LEN];  /*!< Copy of the latest received chunk of data */
-	uint16_t received_chunk_size;            /*!< Size of the chunk in latest_chunk_copy */
+	uint16_t received_chunk_size;       /*!< Size of the chunk in latest_chunk_copy */
 
 	// the readout state
 	uint32_t pos;
 	uint32_t total;
 	ETSTimer abortTimer;
+
+	MEAS_FORMAT format; /*!< Requested data format */
+
+	// --- data stats ---
+	MeasStats stats;
 } rd;
 
 
+bool FLASH_FN meas_is_closed(void)
+{
+	return !rd.pending;
+}
+
+
 // --- timeout ---
 
 static void FLASH_FN abortTimerCb(void *arg)
@@ -40,13 +48,8 @@ static void FLASH_FN abortTimerCb(void *arg)
 	// try to abort the readout
 	sbmp_bulk_abort(dlnk_ep, rd.sesn);
 
-	// free the data obj if not NULL
+	// release resources and stop
-	sbmp_ep_free_listener_obj(dlnk_ep, rd.sesn);
+	meas_close();
-	// release the slot
-	sbmp_ep_remove_listener(dlnk_ep, rd.sesn);
-
-	// invalidate the chunk buffer and indicate that a new readout can start
-	rd.pending = false;
 }
 
 static void FLASH_FN setReadoutTmeoTimer(int ms)
@@ -111,6 +114,8 @@ bool FLASH_FN meas_is_last_chunk(void)
 /** Terminate the readout. */
 void FLASH_FN meas_close(void)
 {
+	if (!rd.pending) return; // ignore this call
+
 	sbmp_ep_remove_listener(dlnk_ep, rd.sesn);
 	stopReadoutTmeoTimer();
 	rd.pending = false;
@@ -118,6 +123,10 @@ void FLASH_FN meas_close(void)
 	info("Transfer closed.");
 }
 
+MeasStats FLASH_FN *meas_get_stats(void)
+{
+	return &rd.stats;
+}
 
 static void FLASH_FN request_data_sesn_listener(SBMP_Endpoint *ep, SBMP_Datagram *dg, void **obj)
 {
@@ -129,7 +138,6 @@ static void FLASH_FN request_data_sesn_listener(SBMP_Endpoint *ep, SBMP_Datagram
 	switch (dg->type) {
 		case DG_BULK_OFFER:// Data ready notification
 			stopReadoutTmeoTimer();
-//			info("--- Peer offers data for bulk transfer ---");
 
 			// data is ready to be read
 			pp = pp_start(dg->payload, dg->length);
@@ -137,10 +145,20 @@ static void FLASH_FN request_data_sesn_listener(SBMP_Endpoint *ep, SBMP_Datagram
 			rd.pos = 0;
 			rd.total = pp_u32(&pp);
 
-//			dbg("Total bytes avail: %d", rd.total);
+			// --- here start the user data (common) ---
+			rd.stats.count = pp_u32(&pp);
+			rd.stats.freq = pp_float(&pp);
+			rd.stats.min = pp_float(&pp);
+			rd.stats.max = pp_float(&pp);
+			rd.stats.rms = pp_float(&pp);
+			// --- user data end ---
+
+			if (rd.format == FFT) {
+				// TODO read extra FFT stats
+			}
 
 			// renew the timeout
-			setReadoutTmeoTimer(READOUT_TMEO);
+			setReadoutTmeoTimer(SAMP_READOUT_TMEO);
 
 			// request first chunk
 			sbmp_bulk_request(ep, rd.pos, CHUNK_LEN, dg->session);
@@ -148,7 +166,6 @@ static void FLASH_FN request_data_sesn_listener(SBMP_Endpoint *ep, SBMP_Datagram
 
 		case DG_BULK_DATA: // data received
 			stopReadoutTmeoTimer();
-//			info("--- Received a chunk, length %d ---", dg->length);
 
 			// Process the received data
 			memcpy(rd.received_chunk, dg->payload, dg->length);
@@ -158,7 +175,9 @@ static void FLASH_FN request_data_sesn_listener(SBMP_Endpoint *ep, SBMP_Datagram
 			// move the pointer for next request
 			rd.pos += dg->length;
 
-			setReadoutTmeoTimer(READOUT_TMEO); // timeout to retrieve the data & ask for more
+			setReadoutTmeoTimer(SAMP_READOUT_TMEO); // timeout to retrieve the data & ask for more
+
+			// --- Now we wait for the CGI func to retrieve the chunk and send it to the browser. ---
 
 			if (rd.pos >= rd.total) {
 				info("Transfer is complete.");
@@ -183,11 +202,11 @@ cleanup:
 }
 
 
-bool FLASH_FN meas_request_data(uint16_t count, uint32_t freq)
+bool FLASH_FN meas_request_data(MEAS_FORMAT format, uint16_t count, uint32_t freq)
 {
 	bool suc = false;
 
-	info("Requesting data capture - %d samples @ %d Hz.", count, freq);
+	info("Requesting data capture - %d samples @ %d Hz, fmt %d.", count, freq, format);
 
 	if (rd.pending) {
 		error("Acquire request already in progress.");
@@ -199,17 +218,20 @@ bool FLASH_FN meas_request_data(uint16_t count, uint32_t freq)
 		return false;
 	}
 
+	// clean up
 	rd.chunk_ready = false;
 	rd.pos = 0;
 	rd.total = 0;
 	rd.pending = true;
+	rd.format = format;
+	memset(&rd.stats, 0, sizeof(MeasStats)); // clear the stats obj
 
 	// start the abort timer - timeout
 	setReadoutTmeoTimer(SAMPLING_TMEO);
 
 	// start a message
 	uint16_t sesn = 0;
-	suc = sbmp_ep_start_message(dlnk_ep, DG_REQUEST_CAPTURE, sizeof(uint16_t)+sizeof(uint32_t), &sesn);
+	suc = sbmp_ep_start_message(dlnk_ep, format, sizeof(uint16_t)+sizeof(uint32_t), &sesn); // format enum matches the message types
 	if (!suc) goto fail;
 
 	// register the session listener
@@ -237,38 +259,3 @@ fail:
 	rd.pending = false;
 	return false;
 }
-
-
-// ------ C G I ---------
-
-
-/*
-int FLASH_FN cgiReadSamples(HttpdConnData *connData)
-{
-	char buff[128];
-
-	if (connData->conn == NULL) {
-		//Connection aborted. Clean up.
-		return HTTPD_CGI_DONE;
-	}
-
-	uint16_t count = 1;
-	int len = httpdFindArg(connData->getArgs, "n", buff, sizeof(buff));
-	if (len != -1) {
-		count = (uint16_t)atoi(buff);
-	}
-
-	dbg("User wants %d samples.", count);
-
-	meas_request_data(count);
-
-	httpdStartResponse(connData, 200);
-	httpdHeader(connData, "Content-Type", "text/plain");
-	httpdEndHeaders(connData);
-
-	// body
-	httpdSend(connData, "OK.", -1);
-
-	return HTTPD_CGI_DONE;
-}
-*/

user/sampling.h

@@ -3,6 +3,24 @@
 
 #include <esp8266.h>
 #include <httpd.h>
+#include "datalink.h"
+
+#define SAMPLING_TMEO 6000
+#define SAMP_READOUT_TMEO 100
+
+typedef struct {
+	uint32_t count;
+	float freq; // actual frequency - not exact due to the prescaller limitations
+	float min;
+	float max;
+	float rms;
+} MeasStats;
+
+typedef enum {
+	RAW = DG_REQUEST_RAW, // same as the SBMP packet numbers used to request it
+	FFT = DG_REQUEST_FFT
+} MEAS_FORMAT;
+
 
 /**
  * Reading procedure
@@ -18,7 +36,7 @@
  */
 
 /** Request data from the sampling module. Count - number of samples. */
-bool meas_request_data(uint16_t count, uint32_t freq); // TODO specify what kind of data - currently direct samples.
+bool meas_request_data(MEAS_FORMAT format, uint16_t count, uint32_t freq); // TODO specify what kind of data - currently direct samples.
 
 /** request next chunk */
 void meas_request_next_chunk(void);
@@ -26,6 +44,12 @@ void meas_request_next_chunk(void);
 /** Check if chunk ready to be read */
 bool meas_chunk_ready(void);
 
+/** Check if closed (if data was expected, this means the peer aborted the transaction) */
+bool meas_is_closed(void);
+
+/** Get the stats struct */
+MeasStats *meas_get_stats(void);
+
 /**
  * @brief Get received chunk. NULL if none.
  *