1 files changed, 38 insertions, 32 deletions

diff --git a/datalog.h b/datalog.h
index 029ec61..da715e8 100644
--- a/datalog.h
+++ b/datalog.h
@@ -1,53 +1,59 @@
 #pragma once
 
-#include <SD.h>
-#include <FS.h>
+#include <mySD.h>
 
 #include "data.h"
 
-/*
-  most of this comes from
-  https://github.com/Xinyuan-LilyGO/LilyGo-T5-Epaper-Series/blob/master/examples/GxEPD_SD_1.02_Example/SD_Example.ino
- */
+const int mySD_CS=13;
+const int mySD_SCLK=14;
+const int mySD_MISO=2;
+const int mySD_MOSI=15;
+
+//                      12345, 12345, 12345, 12345, 123456, 123456, 123456, 123456, 12345\n
+const char csvHeader[]=" secs,   co2,  temp, humid,    pm1,  pm2.5,    pm4,   pm10,  batt\n";
+const char csvFormat[]="% 5lu, % 5u, % 5.1f, % 5.1f, % 6.1f, % 6.1f, % 6.1f, % 6.1f, % 5.2f\n";
+const size_t lineLength=66;
+
 class DataLog {
 private:
-  SPIClass SDSPI;
   File logfile;
   char line[100];
   uint8_t linesSinceLastFlush;
   uint8_t flushThreshold;
 public:
-  DataLog(uint8_t ft=4) : SDSPI(VSPI), flushThreshold(ft) {}
+  DataLog(uint8_t ft=4) : flushThreshold(ft) {}
 
   void start() {
-    SDSPI.begin(SDCARD_SCLK, SDCARD_MISO, SDCARD_MOSI);
-    bool sdok=SD.begin(SDCARD_CS, SDSPI);
+    bool sdok=SD.begin(mySD_CS, mySD_MOSI, mySD_MISO, mySD_SCLK);
     Serial.print("sdok: ");Serial.println(sdok);
-    Serial.println(SD.cardSize());
-    logfile = SD.open("air-quality.csv",FILE_APPEND,true);
-    Serial.print("file: ");Serial.println(logfile.path());
-    linesSinceLastFlush=0;
+    logfile = SD.open("quality.csv",FILE_WRITE);
+    Serial.print("file: ");Serial.println(logfile.name());
+    uint32_t fileSize = logfile.size();
+    logfile.seek(fileSize);
+    if (fileSize == 0) {
+      logfile.write((uint8_t*)csvHeader, lineLength);
+    }                    
+    linesSinceLastFlush=1;
   }
 
   void show(const SensorData *data) {
-    sprintf(
-            line,
-            //milli  co2   temp    humid   pm1     pm2.5   pm4     pm10   battery
-            "% 5lu, % 5u, % 5.1f, % 5.1f, % 6.1f, % 6.1f, % 6.1f, % 6.1f, % 5.2f\n",
-            millis()/1000,
-
-            data->co2,
-            data->temperature,
-            data->humidity,
-
-            data->pm.mc_1p0,
-            max(0.0f,data->pm.mc_2p5 - data->pm.mc_1p0),
-            max(0.0f,data->pm.mc_4p0 - data->pm.mc_2p5),
-            max(0.0f,data->pm.mc_10p0 - data->pm.mc_4p0),
-
-            data->batteryVoltage
-            );
-    size_t written=logfile.write((uint8_t *)line,65);
+    snprintf(
+             line, lineLength+1, // zero terminator!
+             csvFormat,
+             millis()/1000,
+
+             data->co2,
+             data->temperature,
+             data->humidity,
+
+             data->pm.mc_1p0,
+             max(0.0f,data->pm.mc_2p5 - data->pm.mc_1p0),
+             max(0.0f,data->pm.mc_4p0 - data->pm.mc_2p5),
+             max(0.0f,data->pm.mc_10p0 - data->pm.mc_4p0),
+
+             data->batteryVoltage
+             );
+    size_t written=logfile.write((uint8_t *)line,lineLength);
     Serial.write(line);
     Serial.print("written: ");Serial.println(written);
     if (++linesSinceLastFlush > flushThreshold) {