fix data logging

when pm measurements went above 1k, the string got truncated ☹

remove the sign bits from columns that don't need them!

also, uptime can be 6 digits

1 files changed, 14 insertions, 6 deletions

diff --git a/datalog.h b/datalog.h
index 8f7bd81..47833ac 100644
--- a/datalog.h
+++ b/datalog.h
@@ -13,10 +13,18 @@ const int mySD_MOSI=15;
   we write fixed-length CSV lines because, at some point in the
   future, I may need to seek "10 measurements back" or something like
   that; also, it's easier to read
+
+  column ranges and sizes:
+  * secs: up to ~36 hours = 130000, unsigned: 6 characters
+  * co2: up to ~4000, unsigned: 4 characters
+  * temp: -20.0 … +40.0, signed: 5 characters
+  * humid: 0.0 … 100.0, unsigned: 5 characters
+  * pm*: 0.0 … 9999.9, unsigned: 6 characters
+  * batt: 3.00 … 4.30, unsigned: 4 characters
  */
-//                      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";
+//                      123456, 1234, 12345, 12345, 123456, 123456, 123456, 123456, 1234\n
+const char csvHeader[]="  secs,  co2,  temp, humid,    pm1,  pm2.5,    pm4,   pm10, batt\n";
+const char csvFormat[]="% 6lu, % 4u, % 5.1f, %5.1f, %6.1f, %6.1f, %6.1f, %6.1f, %4.2f\n";
 const size_t lineLength=66;
 
 class DataLog {
@@ -49,14 +57,14 @@ public:
 
              data->co2,
              data->temperature,
-             data->humidity,
+             max(0.0f,data->humidity),
 
-             data->pm.mc_1p0,
+             max(0.0f,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
+             max(0.0f,data->batteryVoltage)
              );
     size_t written=logfile.write((uint8_t *)line,lineLength);
     Serial.print("# ");Serial.write(line);