been doing some LoRaWAN tests with the Heltec WiFi32 LoRa V4 attempting to transmit data from a DS18B20 temperature sensors
sometimes worked most of the time failed with -127.00 reading
then tested with a V3 and the LoRaWAN and DS18B20 worked OK
so implemented a simple test program
using a Heltec WiFi32 LoRa V4.3
- on the V3 and V4 DS28B10 test program runs OK gives valid temperatures
- a program which worked OK on the Heltec WiFi32 LoRa V3 using LoRaWAN and a DS18B20 on the V4 gives DS18B20 invalid results
V4 code (the only difference with V3 version was the version number in tile and Serial print)
//Heltec WiFi32 LoRa V4 LoRaWAN test transmitting DS18B20 temperature sensor
// using IDE 2.3.10 ESP32 core 3.3.10 Heltec ESP32 Dev-Boards library 2.1.6
// code adapted from Tools>Board> Heltec ESP32 Dev-Boardslibrary>LoRaWAN>LoRaWAN
// NOTE: in Tools menu select
// USB CDC on Boot: select Enabled
// for V4.3 LoRa FEM Type select USE_KCT8103L_PA.
/* Heltec Automation LoRaWAN communication example
*
* Function:
* 1. Upload node data to the server using the standard LoRaWAN protocol.
*
* Description:
* 1. Communicate using LoRaWAN protocol.
*
* HelTec AutoMation, Chengdu, China
* 成都惠利特自动化科技有限公司
* www.heltec.org
*
* */
#include "LoRaWan_APP.h"
/* OTAA para*/
uint8_t devEui[] = { xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx };
uint8_t appEui[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
uint8_t appKey[] = { zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz};
/* ABP para*/
uint8_t nwkSKey[] = { 0x15, 0xb1, 0xd0, 0xef, 0xa4, 0x63, 0xdf, 0xbe, 0x3d, 0x11, 0x18, 0x1e, 0x1e, 0xc7, 0xda, 0x85 };
uint8_t appSKey[] = { 0xd7, 0x2c, 0x78, 0x75, 0x8c, 0xdc, 0xca, 0xbf, 0x55, 0xee, 0x4a, 0x77, 0x8d, 0x16, 0xef, 0x67 };
uint32_t devAddr = (uint32_t)0x007e6ae1;
/*LoraWan channelsmask, default channels 0-7*/
uint16_t userChannelsMask[6] = { 0x00FF, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000 };
/*LoraWan region, select in arduino IDE tools*/
LoRaMacRegion_t loraWanRegion = ACTIVE_REGION;
/*LoraWan Class, Class A and Class C are supported*/
DeviceClass_t loraWanClass = CLASS_A;
/*the application data transmission duty cycle. value in [ms].*/
uint32_t appTxDutyCycle = 30000;
/*OTAA or ABP*/
bool overTheAirActivation = true;
/*ADR enable*/
bool loraWanAdr = true;
/* Indicates if the node is sending confirmed or unconfirmed messages */
bool isTxConfirmed = true;
/* Application port */
uint8_t appPort = 2;
/*!
* Number of trials to transmit the frame, if the LoRaMAC layer did not
* receive an acknowledgment. The MAC performs a datarate adaptation,
* according to the LoRaWAN Specification V1.0.2, chapter 18.4, according
* to the following table:
*
* Transmission nb | Data Rate
* ----------------|-----------
* 1 (first) | DR
* 2 | DR
* 3 | max(DR-1,0)
* 4 | max(DR-1,0)
* 5 | max(DR-2,0)
* 6 | max(DR-2,0)
* 7 | max(DR-3,0)
* 8 | max(DR-3,0)
*
* Note, that if NbTrials is set to 1 or 2, the MAC will not decrease
* the datarate, in case the LoRaMAC layer did not receive an acknowledgment
*/
uint8_t confirmedNbTrials = 4;
float DStemperature = 0; // DS18B20 temperature
/* Prepares the payload of the frame */
static void prepareTxFrame(uint8_t port) {
/*appData size is LORAWAN_APP_DATA_MAX_SIZE which is defined in "commissioning.h".
*appDataSize max value is LORAWAN_APP_DATA_MAX_SIZE.
*if enabled AT, don't modify LORAWAN_APP_DATA_MAX_SIZE, it may cause system hanging or failure.
*if disabled AT, LORAWAN_APP_DATA_MAX_SIZE can be modified, the max value is reference to lorawan region and SF.
*for example, if use REGION_CN470,
*the max value for different DR can be found in MaxPayloadOfDatarateCN470 refer to DataratesCN470 and BandwidthsCN470 in "RegionCN470.h".
*/
appDataSize = 4;
DS18B20loop();
int temp = (int)((DStemperature + 100) * 100.0);
appData[0] = 0x00;
appData[1] = 0x01;
appData[2] = (temp & 0xff);
appData[3] = (temp >> 8) & 0xff;
}
//if true, next uplink will add MOTE_MAC_DEVICE_TIME_REQ
void setup() {
Serial.begin(115200);
delay(1000);
Serial.println("\n\nHeltec WiFi32 LoRa V4 LoRaWAN test transmitting DS18B20 temperature sensor");
Mcu.begin(HELTEC_BOARD, SLOW_CLK_TPYE);
DS18B20setup();
}
void loop() {
switch (deviceState) {
case DEVICE_STATE_INIT:
{
#if (LORAWAN_DEVEUI_AUTO)
LoRaWAN.generateDeveuiByChipID();
#endif
LoRaWAN.init(loraWanClass, loraWanRegion);
//both set join DR and DR when ADR off
LoRaWAN.setDefaultDR(3);
break;
}
case DEVICE_STATE_JOIN:
{
LoRaWAN.join();
break;
}
case DEVICE_STATE_SEND:
{
prepareTxFrame(appPort);
LoRaWAN.send();
deviceState = DEVICE_STATE_CYCLE;
break;
}
case DEVICE_STATE_CYCLE:
{
// Schedule next packet transmission
txDutyCycleTime = appTxDutyCycle + randr(-APP_TX_DUTYCYCLE_RND, APP_TX_DUTYCYCLE_RND);
LoRaWAN.cycle(txDutyCycleTime);
deviceState = DEVICE_STATE_SLEEP;
break;
}
case DEVICE_STATE_SLEEP:
{
LoRaWAN.sleep(loraWanClass);
break;
}
default:
{
deviceState = DEVICE_STATE_INIT;
break;
}
}
}
// ESP32 DS18B20 one-wire temperature sensors - read the temperature
// connect red 3v black GND yellow (signal) pin 2
/********************************************************************/
// First we include the libraries
#include <OneWire.h>
#include <DallasTemperature.h>
/********************************************************************/
// Data wire is plugged into
#define ONE_WIRE_BUS 7
/********************************************************************/
// Setup a oneWire instance to communicate with any OneWire devices
// (not just Maxim/Dallas temperature ICs)
OneWire oneWire(ONE_WIRE_BUS);
/********************************************************************/
// Pass our oneWire reference to Dallas Temperature.
DallasTemperature sensors(&oneWire);
/********************************************************************/
void DS18B20setup(void) {
Serial.begin(115200);
Serial.println("Dallas Temperature IC Control Library Demo");
// Start up the library
sensors.begin();
}
void DS18B20loop(void) {
// call sensors.requestTemperatures() to issue a global temperature
// request to all devices on the bus
/********************************************************************/
Serial.print("\nRequesting temperatures...");
sensors.requestTemperatures(); // Send the command to get temperature readings
Serial.println("DONE");
/********************************************************************/
Serial.print("Temperature is: ");
Serial.println(DStemperature = sensors.getTempCByIndex(0)); // Why "byIndex"?
// You can have more than one DS18B20 on the same bus.
// 0 refers to the first IC on the wire
delay(1000);
}
Heltec WiFi32 LoRa V3 serial output
Heltec WiFi32 LoRa V3 LoRaWAN test transmitting DS18B20 temperature sensor
Dallas Temperature IC Control Library Demo
LoRaWAN EU868 Class A start!
+OTAA=1
+Class=A
+ADR=1
+IsTxConfirmed=1
+AppPort=2
+DutyCycle=30000
+ConfirmedNbTrials=4
+ChMask=0000000000000000000000FF
+DevEui=xxxxxxxxxxxxxxxxxxxxxxxxxxxxx(For OTAA Mode)
+AppEui=0000000000000000(For OTAA Mode)
+AppKey=zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz(For OTAA Mode)
+NwkSKey=15B1D0EFA463DFBE3D11181E1EC7DA85(For ABP Mode)
+AppSKey=D72C78758CDCCABF55EE4A778D16EF67(For ABP Mode)
+DevAddr=007E6AE1(For ABP Mode)
joining...
joined
Requesting temperatures...DONE
Temperature is: 23.50
confirmed uplink sending ...
received unconfirmed downlink: rssi = -47, snr = 13, datarate = 5
Heltec WiFi32 LoRa V3 LoRaWAN test transmitting DS18B20 temperature sensor
Dallas Temperature IC Control Library Demo
Requesting temperatures...DONE
Temperature is: 28.50
confirmed uplink sending ...
received unconfirmed downlink: rssi = -47, snr = 13, datarate = 5
Heltec WiFi32 LoRa V3 LoRaWAN test transmitting DS18B20 temperature sensor
Dallas Temperature IC Control Library Demo
Requesting temperatures...DONE
Temperature is: 32.00
confirmed uplink sending ...
received unconfirmed downlink: rssi = -45, snr = 13, datarate = 5
Heltec WiFi32 LoRa V4 serial output
Heltec WiFi32 LoRa V4 LoRaWAN test transmitting DS18B20 temperature sensor
Dallas Temperature IC Control Library Demo
LoRaWAN EU868 Class A start!
joining...
joined
Requesting temperatures...DONE
Temperature is: -127.00
confirmed uplink sending ...
received unconfirmed downlink: rssi = -42, snr = 14, datarate = 5
Heltec WiFi32 LoRa V4 LoRaWAN test transmitting DS18B20 temperature sensor
Dallas Temperature IC Control Library Demo
Requesting temperatures...DONE
Temperature is: -127.00
confirmed uplink sending ...
it can seen that the DS18B20 is read without problems using the V3 but gives -127.00 with the V4 - any ideas?
TTN output for V3
