add examples (#16)

- add LORA example
- add Multiplexer example
- update readme.md
- minor edits.

CHANGELOG.md

@@ -6,6 +6,12 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 
+## [0.3.1] - 2024-01-01
+- add LORA example
+- add Multiplexer example
+- update readme.md
+- minor edits.
+
 ## [0.3.0] - 2023-12-08
 - refactor API, begin()
 - update readme.md

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2021-2023 Rob Tillaart
+Copyright (c) 2021-2024 Rob Tillaart
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -78,6 +78,8 @@ or switch the VCC as a sort of ChipSelect signal.
 
 - https://github.com/RobTillaart/TCA9548  (I2C 8 channel multiplexer)
 
+See **TCA9548_demo_SGP30.ino** example.
+
 
 #### Related
 
@@ -127,10 +129,10 @@ Note the measurement is slow as there is an active blocking until the sensor is
 If the last measurement is less than a second ago, no measurement is made and the function returns false.
 
 
-#### A-synchronous measurements
+#### Asynchronous measurements
 
 With the async interface, the user should control that reads are at least one second apart. 
-The user should also take care not to mix up different requests. See examples. 
+The user should also take care not to mix up different requests. See examples.
 
 - **void request()** sends a request to the sensor to read CO2 and TVOC. 
 - **bool read()** returns true if the last request is more than 12 milliseconds ago the 
@@ -208,9 +210,9 @@ The used references are based upon
 (2) the assumption that this is 0.4 resp 0.5 ppm. 
 (Note only 1 significant digit) as mentioned in datasheet P2.
 
-- **void  setSrefH2(uint16_t s = 13119)** // 13119 is my measurement.
+- **void  setSrefH2(uint16_t s = 13119)**  13119 is my measurement.
 - **uint16_t getSrefH2()** returns value set.
-- **void setSrefEthanol(uint16_t s = 18472)** // 18472 is my measurement.
+- **void setSrefEthanol(uint16_t s = 18472)** 18472 is my measurement.
 - **uint16_t getSrefEthanol()** returns value set.
 
 
@@ -229,7 +231,6 @@ The used references are based upon
 #### Could
 
 - move code from .h to .cpp
-- improve/merge the private **command()** function
 - add/extend error handling
 - better name for **measureTest()**
 
@@ -241,6 +242,7 @@ for the smallest platforms e.g. tiny.
 
 - make defines for the magic numbers (commands)
   - only used once.
+- improve/merge the private **command()** function (made no difference)
 
 
 ## Support

SGP30.cpp

@@ -1,7 +1,7 @@
 //
 //    FILE: SGP30.cpp
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.3.0
+// VERSION: 0.3.1
 //    DATE: 2021-06-24
 // PURPOSE: Arduino library for SGP30 environment sensor.
 //     URL: https://github.com/RobTillaart/SGP30
@@ -17,15 +17,16 @@
 //
 SGP30::SGP30(TwoWire *wire)
 {
-  _address  = 0x58;
   _wire     = wire;
+  _address  = 0x58;  //  Fixed!
 
   _tvoc     = 0;
   _co2      = 0;
   _h2       = 0;
   _ethanol  = 0;
 
   _lastTime = 0;
+  _lastRequest = 0;
   _error    = SGP30_OK;
 }
 

SGP30.h

@@ -2,7 +2,7 @@
 //
 //    FILE: SGP30.h
 //  AUTHOR: Rob Tillaart
-// VERSION: 0.3.0
+// VERSION: 0.3.1
 //    DATE: 2021-06-24
 // PURPOSE: Arduino library for SGP30 environment sensor.
 //     URL: https://github.com/RobTillaart/SGP30
@@ -12,7 +12,7 @@
 #include "Arduino.h"
 #include "Wire.h"
 
-#define SGP30_LIB_VERSION               (F("0.3.0"))
+#define SGP30_LIB_VERSION               (F("0.3.1"))
 
 #define SGP30_OK                        0x00
 #define SGP30_ERROR_CRC                 0xFF
@@ -95,13 +95,14 @@ class SGP30
 private:
   uint8_t  _address;
   int      _error;
-  uint32_t _lastTime    = 0;
-  uint32_t _lastRequest = 0;
+  uint32_t _lastTime;
+  uint32_t _lastRequest;
 
   //  TODO improve?
   int      _command(uint16_t cmd);
   int      _command(uint16_t cmd, uint16_t v1);
   int      _command(uint16_t cmd, uint16_t v1, uint16_t v2);
+
   uint8_t  _CRC8(uint16_t val);
   void     _init();
 

examples/TCA9548_demo_SGP30/.arduino-ci.yml

@@ -0,0 +1,30 @@
+platforms:
+  rpipico:
+    board: rp2040:rp2040:rpipico
+    package: rp2040:rp2040
+    gcc:
+      features:
+      defines:
+        - ARDUINO_ARCH_RP2040
+      warnings:
+      flags:
+
+packages:
+  rp2040:rp2040:
+    url: https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json
+
+compile:
+  # Choosing to run compilation tests on 2 different Arduino platforms
+  platforms:
+    - uno
+    # - due
+    # - zero
+    # - leonardo
+    - m4
+    - esp32
+    - esp8266
+    # - mega2560
+    - rpipico
+  libraries:
+    - "AM232X"
+    - "TCA9548"

examples/TCA9548_demo_SGP30/TCA9548_demo_SGP30.ino

@@ -0,0 +1,82 @@
+//
+//    FILE: TCA9548_demo_SGP30.ino
+//  AUTHOR: Rob Tillaart
+// PURPOSE: demo TCA9548 I2C multiplexer
+//     URL: https://github.com/RobTillaart/TCA9548
+//     URL: https://github.com/RobTillaart/SGP30
+
+
+#include "SGP30.h"
+#include "TCA9548.h"
+
+PCA9546 MP(0x70);
+uint8_t channels = 0;
+
+SGP30 living;    //  channel 0
+SGP30 kitchen;   //  channel 1
+SGP30 outside;   //  channel 2
+
+uint32_t lastTime = 0;
+
+void setup()
+{
+  Serial.begin(115200);
+  Serial.println(__FILE__);
+  Serial.print("TCA9548_LIB_VERSION: ");
+  Serial.println(TCA9548_LIB_VERSION);
+  Serial.print("SGP30_LIB_VERSION: ");
+  Serial.println(SGP30_LIB_VERSION);
+  Serial.println();
+
+  Wire.begin();
+  //  initialize multiplexer
+  if (MP.begin() == false)
+  {
+    Serial.println("Multiplexer error");
+  }
+  channels = MP.channelCount();
+
+  //  initialize the temperature sensors
+  MP.selectChannel(0);
+  if (living.begin() == false)
+  {
+    Serial.println("living error");
+  }
+  MP.selectChannel(1);
+  if (kitchen.begin() == false )
+  {
+    Serial.println("kitchen error");
+  }
+  MP.selectChannel(2);
+  if (outside.begin() == false )
+  {
+    Serial.println("outside error");
+  }
+}
+
+
+void loop()
+{
+  if ((millis() - lastTime) > 5000)
+  {
+    lastTime = millis();
+
+    MP.selectChannel(0);
+    living.read();
+    Serial.print(living.getCO2(), 1);
+    Serial.print("\t");
+
+    MP.selectChannel(1);
+    kitchen.read();
+    Serial.print(kitchen.getCO2(), 1);
+    Serial.print("\t");
+
+    MP.selectChannel(2);
+    outside.read();
+    Serial.print(outside.getCO2(), 1);
+    Serial.print("\n");
+  }
+}
+
+
+//  -- END OF FILE --

library.json

@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/SGP30.git"
   },
-  "version": "0.3.0",
+  "version": "0.3.1",
   "license": "MIT",
   "frameworks": "*",
   "platforms": "*",

library.properties

@@ -1,5 +1,5 @@
 name=SGP30
-version=0.3.0
+version=0.3.1
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Arduino library for SGP30 environment sensor.