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Validate DS18B20 CRC #14

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71 changes: 52 additions & 19 deletions STM32CubeExpansion_LRWAN/Drivers/BSP/Components/ds18b20/ds18b20.c
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Original file line number Diff line number Diff line change
Expand Up @@ -515,13 +515,27 @@ void DS18B20_SkipRom(uint8_t num)
DS18B20_Presence(num);
DS18B20_WriteByte(0XCC,num);
}

float DS18B20_GetTemp_SkipRom (uint8_t num)
unsigned char DS18B20_crc8(const unsigned char * data, const unsigned int size)
{
unsigned char crc = 0;
for ( unsigned int i = 0; i < size; ++i )
{
unsigned char inbyte = data[i];
for ( unsigned char j = 0; j < 8; ++j )
{
unsigned char mix = (crc ^ inbyte) & 0x01;
crc >>= 1;
if ( mix ) crc ^= 0x8C;
inbyte >>= 1;
}
}
return crc;
}
float DS18B20_GetTemp_SkipRom (uint8_t num, bool *success)
{
uint8_t tpmsb, tplsb;
short s_tem;
float f_tem;

uint8_t scratchpad[9];

DS18B20_SkipRom(num);
DS18B20_WriteByte(0X44,num);
Expand All @@ -531,32 +545,51 @@ float DS18B20_GetTemp_SkipRom (uint8_t num)
DS18B20_SkipRom (num);
DS18B20_WriteByte(0XBE,num);

tplsb = DS18B20_ReadByte(num);
tpmsb = DS18B20_ReadByte(num);
scratchpad[0] = DS18B20_ReadByte(num); // LSB
scratchpad[1] = DS18B20_ReadByte(num); // MSB

if((tpmsb==5)&&(tplsb==80)) //1360= 00000101 01010000,tpmsb=00000101=5,tplsb=01010000=80;
if((scratchpad[0]==5)&&(scratchpad[1]==80)) //1360= 00000101 01010000,tpmsb=00000101=5,tplsb=01010000=80;
{
DS18B20_SkipRom(num);
DS18B20_WriteByte(0X44,num);

DelayMs(750);

DS18B20_SkipRom (num);
DS18B20_WriteByte(0XBE,num);
// The power-on reset value of the temperature register is 00000101 01010000, so read it again
DS18B20_SkipRom(num);
DS18B20_WriteByte(0X44,num);

tplsb = DS18B20_ReadByte(num);
tpmsb = DS18B20_ReadByte(num);
DelayMs(750);

DS18B20_SkipRom (num);
DS18B20_WriteByte(0XBE,num);

scratchpad[0] = DS18B20_ReadByte(num); // LSB
scratchpad[1] = DS18B20_ReadByte(num); // MSB
}

s_tem = tpmsb<<8;
s_tem = s_tem | tplsb;
// Receive the rest of the scratchpad
scratchpad[2] = DS18B20_ReadByte(num);// User byte 1
scratchpad[3] = DS18B20_ReadByte(num);// User byte 2
scratchpad[4] = DS18B20_ReadByte(num);// Configuration register
scratchpad[5] = DS18B20_ReadByte(num);// Reserved FFh
scratchpad[6] = DS18B20_ReadByte(num);// Reserved
scratchpad[7] = DS18B20_ReadByte(num);// Reserved 10h
scratchpad[8] = DS18B20_ReadByte(num);// CRC

// output scratchpad for debugging purposes
//PPRINTF("Scratchpad contents: %02x%02x%02x%02x%02x%02x%02x%02x%02x\r\n",
// scratchpad[0], scratchpad[1], scratchpad[2], scratchpad[3],
// scratchpad[4], scratchpad[5], scratchpad[6], scratchpad[7],
// scratchpad[8]);

// calculate CRC and match it against reported one
(*success) = DS18B20_crc8(scratchpad, 8) == scratchpad[8]; // Reserved FFh

s_tem = scratchpad[1]<<8;
s_tem = s_tem | scratchpad[0];

if( s_tem < 0 )
f_tem = (~s_tem+1) * -0.0625;
else
f_tem = s_tem * 0.0625;

// PPRINTF("temp is %f\r\n",f_tem);
//PPRINTF("temp is %f, status %i\r\n",f_tem, (*success));
return f_tem;
}
/*******END OF FILE********/
Expand Down
2 changes: 1 addition & 1 deletion STM32CubeExpansion_LRWAN/Drivers/BSP/Components/ds18b20/ds18b20.h
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Original file line number Diff line number Diff line change
Expand Up @@ -89,7 +89,7 @@ uint8_t DS18B20_ReadByte(uint8_t num);
void DS18B20_WriteBit(uint8_t dat,uint8_t num);
void DS18B20_WriteByte(uint8_t dat,uint8_t num);
void DS18B20_SkipRom(uint8_t num);
float DS18B20_GetTemp_SkipRom (uint8_t num);
float DS18B20_GetTemp_SkipRom (uint8_t num, bool *success);
#ifdef __cplusplus
}
#endif
Expand Down
5 changes: 5 additions & 0 deletions STM32CubeExpansion_LRWAN/Projects/Multi/Applications/LoRa/DRAGINO-LRWAN(AT)/inc/bsp.h
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Original file line number Diff line number Diff line change
Expand Up @@ -66,17 +66,22 @@ Maintainer: Miguel Luis and Gregory Cristian
extern "C" {
#endif
/* Includes ------------------------------------------------------------------*/
#include <stdbool.h>

/* Exported types ------------------------------------------------------------*/

typedef struct{

int in1;/*GPIO Digital Input 0 or 1*/

float temp1;//DS18B20-1
bool temp1_ok;//DS18B20-1

float temp2;//DS18B20-2
bool temp2_ok;//DS18B20-2

float temp3;//DS18B20-3
bool temp3_ok;//DS18B20-3

float oil; //oil float

Expand Down
6 changes: 3 additions & 3 deletions STM32CubeExpansion_LRWAN/Projects/Multi/Applications/LoRa/DRAGINO-LRWAN(AT)/src/bsp.c
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Original file line number Diff line number Diff line change
Expand Up @@ -130,7 +130,7 @@ void BSP_sensor_Read( sensor_t *sensor_data)

sensor_data->in1=HAL_GPIO_ReadPin(GPIO_INPUT_PORT,GPIO_INPUT_PIN1);

sensor_data->temp1=DS18B20_GetTemp_SkipRom(1);
sensor_data->temp1=DS18B20_GetTemp_SkipRom(1, &sensor_data->temp1_ok);

if((mode==1)||(mode==3))
{
Expand Down Expand Up @@ -197,8 +197,8 @@ void BSP_sensor_Read( sensor_t *sensor_data)

else if(mode==4)
{
sensor_data->temp2=DS18B20_GetTemp_SkipRom(2);
sensor_data->temp3=DS18B20_GetTemp_SkipRom(3);
sensor_data->temp2=DS18B20_GetTemp_SkipRom(2, &sensor_data->temp2_ok);
sensor_data->temp3=DS18B20_GetTemp_SkipRom(3, &sensor_data->temp3_ok);
}

else if(mode==5)
Expand Down
67 changes: 49 additions & 18 deletions STM32CubeExpansion_LRWAN/Projects/Multi/Applications/LoRa/DRAGINO-LRWAN(AT)/src/main.c
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Original file line number Diff line number Diff line change
Expand Up @@ -438,10 +438,13 @@ static void Send( void )
{
AppData.Buff[i++] =(batteryLevel_mV>>8); //level of battery in mV
AppData.Buff[i++] =batteryLevel_mV & 0xFF;

AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);

if(sensor_data.temp1_ok){
AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
}else{
AppData.Buff[i++]=0x80;
AppData.Buff[i++]=0x00;
}
AppData.Buff[i++] =(int)(sensor_data.oil)>>8; //oil float
AppData.Buff[i++] =(int)sensor_data.oil;

Expand Down Expand Up @@ -479,8 +482,13 @@ static void Send( void )
AppData.Buff[i++] =(batteryLevel_mV>>8); //level of battery in mV
AppData.Buff[i++] =batteryLevel_mV & 0xFF;

AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
if(sensor_data.temp1_ok){
AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
}else{
AppData.Buff[i++]=0x80;
AppData.Buff[i++]=0x00;
}

AppData.Buff[i++] =(int)(sensor_data.oil)>>8; //oil float
AppData.Buff[i++] =(int)sensor_data.oil;
Expand Down Expand Up @@ -556,8 +564,13 @@ static void Send( void )
AppData.Buff[i++] =(batteryLevel_mV>>8); //level of battery in mV
AppData.Buff[i++] =batteryLevel_mV & 0xFF;

AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
if(sensor_data.temp1_ok){
AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
}else{
AppData.Buff[i++]=0x80;
AppData.Buff[i++]=0x00;
}

AppData.Buff[i++] =(int)(sensor_data.oil)>>8; //oil float
AppData.Buff[i++] =(int)sensor_data.oil;
Expand All @@ -572,21 +585,34 @@ static void Send( void )
switch_status=HAL_GPIO_ReadPin(GPIO_EXTI_PORT,GPIO_EXTI_PIN);
AppData.Buff[i++]=(switch_status<<7)|(sensor_data.in1<<1)|0x0C;
}

AppData.Buff[i++]=(int)(sensor_data.temp2*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp2*10);
AppData.Buff[i++]=(int)(sensor_data.temp3*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp3*10);
if(sensor_data.temp2_ok){
AppData.Buff[i++]=(int)(sensor_data.temp2*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp2*10);
}else{
AppData.Buff[i++]=0x80;
AppData.Buff[i++]=0x00;
}
if(sensor_data.temp3_ok){
AppData.Buff[i++]=(int)(sensor_data.temp3*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp3*10);
}else{
AppData.Buff[i++]=0x80;
AppData.Buff[i++]=0x00;
}

}

else if(mode==5)
{
AppData.Buff[i++] =(batteryLevel_mV>>8); //level of battery in mV
AppData.Buff[i++] =batteryLevel_mV & 0xFF;

AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
if(sensor_data.temp1_ok){
AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
}else{
AppData.Buff[i++]=0x80;
AppData.Buff[i++]=0x00;
}

AppData.Buff[i++] =(int)(sensor_data.oil)>>8; //oil float
AppData.Buff[i++] =(int)sensor_data.oil;
Expand All @@ -613,8 +639,13 @@ static void Send( void )
AppData.Buff[i++] =(batteryLevel_mV>>8); //level of battery in mV
AppData.Buff[i++] =batteryLevel_mV & 0xFF;

AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
if(sensor_data.temp1_ok){
AppData.Buff[i++]=(int)(sensor_data.temp1*10)>>8; //DS18B20
AppData.Buff[i++]=(int)(sensor_data.temp1*10);
}else{
AppData.Buff[i++]=0x80;
AppData.Buff[i++]=0x00;
}

AppData.Buff[i++] =(int)(sensor_data.oil)>>8; //oil float
AppData.Buff[i++] =(int)sensor_data.oil;
Expand Down