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Renesas R7FA8D1BH (Cortex®-M85) controls DS18B20

2024-07-12

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Table of contents

Overview

1 Hardware and Software

1.1 Software and hardware environment information

1.2 Development Board Information

1.3 Debugger Information

2 FSP and KEIL Configuration

2.1 Hardware interface circuit

2.2 FSB configures DS18B20 IO

2.3 Generate Keil project files

3 DS18B20 driver code

3.1 DS18B20 Introduction

3.2 DS18B20 driver implementation

3.2.1 IO status definition

3.2.2 Read IO status function

3.2.3 Other functions

4 Testing Procedure

4.1 Application Design

4.2 Testing

5 Attachments

Renesas R7FA8D1BH (Cortex®-M85) controls DS18B20 and ADC to implement the jump function between two pages

Overview

This article mainly introduces a comprehensive application case designed by Renesas R7FA8D1BH (Cortex®-M85): using the IO of R7FA8D1BH to implement a single bus protocol and realize the function of driving ds18b20, which mainly completes the reading of temperature values ​​and formats the values ​​and displays them on the OLED screen. It also sends the temperature data to the serial terminal through the serial terminal.

1 Hardware and Software

1.1 Software and hardware environment information

Software and hardware informationVersion Information
Renesas MCUR7FA8D1BH
KeilMDK ARM 5.38
FSP version5.3.0
Debug tool: N32G45XVL-STBDAP-LINK

1.2 Development Board Information

The author chose to use the WildFire Yaoyang Development Board_Renesas RA8. The main control MCU of this board is R7FA8D1BHECBD, and the core of 7FA8D1BHECBD is ARM Contex-M85.

1.3 Debugger Information

For the R7FA8D1BHECBD chip, which uses the Cortex®-M85 Core, ST-LINK-V2 or J-LINK-V9 does not support download and debug functions. After many attempts, I foundN32G45XVL-STBThe DAP-LINK on the board can download and debug R7FA8D1BHECBD.

The following figure is a physical picture of the N32G45XVL-STB development board:

2 FSP and KEIL Configuration

2.1 Hardware interface circuit

The interface circuit of DS18B20 has been designed on Yaoyang development board_Renesas RA8, which uses P809 interface as the DQ control signal of DS18B20.

2.2 FSB configures DS18B20 IO

Configure P809 as a normal IO interface, and then dynamically configure the output or output status of the IO in the code

2.3 Generate Keil project files

After completing the FSP parameter configuration, you can Generate Project. Open the project file, and its structure is as follows:

Create the ds18b20.c file to implement the driver code

3 DS18B20 driver code

3.1 DS18B20 Introduction

In my previous article, I have analyzed the timing and implementation logic of DS18B20 in detail, so I will not introduce it here.

DS18B20 Application Notes_ds18b20 reads data waveform -CSDN blog

3.2 DS18B20 driver implementation

3.2.1 IO status definition

Line 14 of the code: Define the us step delay function

Line 15 of the code: Define the delay function with a step length of ms

Code line 18: Define the IO PIN of DS18B20

Code line 21: Input port configuration

Code line 22: Output port configuration

Code line 24: Set IO low level

Code line 25: Set IO high level

3.2.2 Read IO status function

Code line 47: Read the IO status in input mode

3.2.3 Other functions

Function: ds18b20Init, detect whether DS18B20 is online

Function: ds18b20BlockModeProcess. Read the value of DS18B20

  1. /**
  2.   * @brief  reset DS18B20
  3.   * @note   if reset ds18b20 sucess, the return value is TRUE
  4.   * @param  None
  5.   * @retval True or Flalse
  6.   */
  7. static uint8_t ds18b20Init( void )
  8. {
  9.     uint16_t tempCnt = 0;
  10.     bsp_io_level_t status;
  11.    
  12.     // Set PIN mode output
  13.     DS_Mode_Out_PP();
  14.     
  15.     // Master pin is high 
  16.     DQ_SET_HIGH;
  17.     timeDelayUS(10);
  18.     
  19.     // Master pin is low 
  20.     DQ_SET_LOW;
  21.     // wait for 600 us 
  22.     timeDelayUS(750);
  23.     
  24.     // Set PIN mode input
  25.     DS_Mode_IN_PUT();
  26.     
  27.     while(1)
  28.     {
  29.         status = DQ_RAD_PIN();
  30.         if( status == 0)
  31.         {
  32.             tempCnt = 0;
  33.             return TRUE;
  34.         }
  35.         else
  36.         {
  37.           timeDelayUS(1);
  38.           tempCnt++;
  39.           if( tempCnt > 480 )
  40.               return FALSE;
  41.         }
  42.     }
  43. }
  44.  
  45.  
  46. static uint8_t readBit( void )
  47. {
  48.     uint8_t readCnt = 2;
  49.     uint8_t bitVal = 1;
  50.  
  51.     DQ_SET_LOW;
  52.     timeDelayUS(3);
  53.     DQ_SET_HIGH;
  54.     
  55.     timeDelayUS(5); // 15 us 
  56.     
  57.     while(readCnt-- )
  58.     {
  59.         //read DQ value 
  60.         if( DQ_RAD_PIN() == 0)
  61.         {
  62.            bitVal = 0;
  63.         }
  64.         timeDelayUS(2);  // 15 us 
  65.     }
  66.     
  67.     timeDelayUS(30);      // 15 us 
  68.  
  69.     return  bitVal;
  70. }
  71.  
  72. static uint8_t ds18b20ReadByte( void )
  73. {
  74.    uint8_t byteVal = 0;
  75.     
  76.    for ( uint8_t i = 0; i < 8; i++ )
  77.    {
  78.         byteVal >>= 1;
  79.        
  80.         uint8_t bitVal = readBit(); 
  81.         if( bitVal > 0)
  82.         {
  83.             byteVal |= 0x80;
  84.         }
  85.     }
  86.    
  87.     return  byteVal;
  88. }
  89.  
  90.  
  91. /**
  92.   * @brief  write one byte to DS18B20
  93.   * @note   
  94.   * @param  byte: the data that is sended to ds18b20
  95.   * @retval None
  96.   */
  97. void ds18b20WriteByte( uint8_t byte)
  98. {
  99.     unsigned char k;
  100.     
  101.     // Set PIN mode output
  102.     DS_Mode_Out_PP();
  103.     
  104.     for ( k = 0; k < 8; k++ )
  105.     {
  106.         if (byte & (1<<k))
  107.         {
  108.             DQ_SET_LOW;
  109.             timeDelayUS(2); 
  110.  
  111.             DQ_SET_HIGH;
  112.             timeDelayUS(65); 
  113.         }
  114.         else
  115.         {
  116.             DQ_SET_LOW;
  117.             timeDelayUS(65); 
  118.  
  119.             DQ_SET_HIGH;
  120.             timeDelayUS(2); 
  121.         }
  122.     }
  123. }
  124.  
  125. uint8_t ds18b20BlockModeProcess( void )
  126. {
  127.     uint16_t tempValue;
  128.     uint8_t tempL, tempH;
  129.  
  130.     if (ds18b20Init() == FALSE)
  131.     {
  132.         return FALSE;
  133.     }
  134.  
  135.     // wait for 600 us 
  136.     timeDelayUS(600);
  137.     
  138.     ds18b20WriteByte(0xcc);
  139.     ds18b20WriteByte(0x44);  // start convert temperature 
  140.  
  141.     if (ds18b20Init() == FALSE)
  142.     {
  143.         return FALSE;
  144.     }
  145.     // wait for 600 us 
  146.     timeDelayUS(600);
  147.  
  148.     ds18b20WriteByte(0xcc);
  149.     ds18b20WriteByte(0xbe);  // read temperature data register
  150.  
  151.     tempL = ds18b20ReadByte();
  152.     tempH = ds18b20ReadByte();
  153.     
  154.     if (tempH > 0x7f) 
  155.     {
  156.         tempL    = ~tempL;
  157.         tempH    = ~tempH+1; 
  158.         st_ds1b20val.sign = 1;
  159.     }
  160.  
  161.     tempValue = (uint16_t)((tempH << 8) | tempL);
  162.  
  163.     st_ds1b20val.temperatureVal = (float)(tempValue * 0.0625);
  164.     
  165.     return TRUE;
  166. }
  167.  
  168.  
  169. // NO blocking mode operate ds18b20 
  170. uint8_t ds18b20NoBlockingProcess( void )
  171. {
  172.     uint16_t tempValue;
  173.     static uint16_t waitCnt = 0;
  174.     uint8_t tempL, tempH;
  175.     static  uint8_t runState = 0;
  176.     
  177.     switch( runState )
  178.     {
  179.         default:
  180.         case INIT_DQ:
  181.             if (ds18b20Init() == FALSE)
  182.             {
  183.                 return FALSE;
  184.             }
  185.             runState = WAIT_READY;
  186.             break;
  187.             
  188.         case WAIT_READY:
  189.             timeDelayUS(2);       // IDEL 
  190.             runState = SKIDROM_CMD;
  191.             break;
  192.            
  193.        case SKIDROM_CMD:
  194.             ds18b20WriteByte(0xcc);
  195.             ds18b20WriteByte(0x44);  // begin to convert temperature data
  196.             waitCnt = 0;
  197.             runState = WAIT_CONVERT;
  198.             break;
  199.        
  200.        case WAIT_CONVERT:
  201.            waitCnt++;
  202.            if( waitCnt > WAIT_CNT_CONVERT)
  203.            {
  204.                waitCnt = 0;
  205.                runState = RESET_CMD;
  206.            }
  207.            break;
  208.         
  209.         case RESET_CMD:
  210.             if (ds18b20Init() == FALSE)
  211.             {
  212.                 return FALSE;
  213.             }
  214.             runState = WAIT_DATA_READY;
  215.             break;
  216.             
  217.         case WAIT_DATA_READY: 
  218.             timeDelayUS(2);     // IDEL 
  219.             runState = READ_CMD;
  220.             break;
  221.             
  222.         case READ_CMD:
  223.             ds18b20WriteByte(0xcc);
  224.             ds18b20WriteByte(0xbe);  // read temperature data register
  225.             runState = GET_VALUE;
  226.             break;
  227.             
  228.         case GET_VALUE:
  229.  
  230.             tempL = ds18b20ReadByte();
  231.             tempH = ds18b20ReadByte();
  232.  
  233.             if (tempH > 0x7f) 
  234.             {
  235.                 tempL    = ~tempL;
  236.                 tempH    = ~tempH+1; 
  237.                 st_ds1b20val.sign = 1;
  238.             }
  239.  
  240.             tempValue = (uint16_t)((tempH << 8) | tempL);
  241.  
  242.             st_ds1b20val.temperatureVal = (float)(tempValue * 0.0625);
  243.             runState = INIT_DQ;
  244.             return TRUE;
  245.     }
  246.     
  247.     return FALSE;
  248. }

4 Testing Procedure

4.1 Application Design

Code line 113: Read the value of ds18b20

Code line 130: Get the result data of ds18b20

Code line 131: Formatting display data

Code line 132: Display data on OLED

4.2 Testing

Compile the code and download it to the board. The running results are as follows:

5 Attachments

DS18B20 driver code

1) Create the ds18b20.c file and write the following code

  1.  /*
  2.  FILE NAME  :  ds18b20.c
  3.  Description:  user ds18b20 interface 
  4.  Author     :  [email protected]
  5.  Date       :  2024/06/03
  6.  */
  7. #include "ds18b20.h" 
  8. #include "hal_data.h"
  9.  
  10. typedef enum{
  11.   INPUT = 0,
  12.   OUTPUT = 1,
  13. }IO_TYPE;
  14.  
  15. typedef enum{
  16.   FALSE = 0,
  17.   TRUE = 1,
  18. }RETURN_RESULT;
  19.  
  20. typedef enum{
  21.    INIT_DQ = 0,
  22.    WAIT_READY,
  23.    SKIDROM_CMD,
  24.     
  25.    WAIT_CONVERT,
  26.    RESET_CMD,
  27.    READ_CMD,
  28.  
  29.    WAIT_DATA_READY,
  30.    GET_VALUE,
  31.    IDLE_NULL
  32. }RUN_STATE;
  33.  
  34. ds18b20Struc st_ds1b20val;
  35.  
  36.  
  37. ds18b20Struc get_ds18b20_value( void )
  38. {
  39.     return st_ds1b20val;
  40. }
  41.  
  42. static bsp_io_level_t DQ_RAD_PIN(void)
  43. {
  44.     bsp_io_level_t state;
  45.  
  46.     // READ io
  47.     R_IOPORT_PinRead(&g_ioport_ctrl, DS_IO_PORT_PIN, &state);
  48.     
  49.     return state;
  50. }
  51.  
  52. /**
  53.   * @brief  reset DS18B20
  54.   * @note   if reset ds18b20 sucess, the return value is TRUE
  55.   * @param  None
  56.   * @retval True or Flalse
  57.   */
  58. static uint8_t ds18b20Init( void )
  59. {
  60.     uint16_t tempCnt = 0;
  61.     bsp_io_level_t status;
  62.    
  63.     // Set PIN mode output
  64.     DS_Mode_Out_PP();
  65.     
  66.     // Master pin is high 
  67.     DQ_SET_HIGH;
  68.     timeDelayUS(10);
  69.     
  70.     // Master pin is low 
  71.     DQ_SET_LOW;
  72.     // wait for 600 us 
  73.     timeDelayUS(750);
  74.     
  75.     // Set PIN mode input
  76.     DS_Mode_IN_PUT();
  77.     
  78.     while(1)
  79.     {
  80.         status = DQ_RAD_PIN();
  81.         if( status == 0)
  82.         {
  83.             tempCnt = 0;
  84.             return TRUE;
  85.         }
  86.         else
  87.         {
  88.           timeDelayUS(1);
  89.           tempCnt++;
  90.           if( tempCnt > 480 )
  91.               return FALSE;
  92.         }
  93.     }
  94. }
  95.  
  96.  
  97. static uint8_t readBit( void )
  98. {
  99.     uint8_t readCnt = 2;
  100.     uint8_t bitVal = 1;
  101.  
  102.     DQ_SET_LOW;
  103.     timeDelayUS(3);
  104.     DQ_SET_HIGH;
  105.     
  106.     timeDelayUS(5); // 15 us 
  107.     
  108.     while(readCnt-- )
  109.     {
  110.         //read DQ value 
  111.         if( DQ_RAD_PIN() == 0)
  112.         {
  113.            bitVal = 0;
  114.         }
  115.         timeDelayUS(2);  // 15 us 
  116.     }
  117.     
  118.     timeDelayUS(30);      // 15 us 
  119.  
  120.     return  bitVal;
  121. }
  122.  
  123. static uint8_t ds18b20ReadByte( void )
  124. {
  125.    uint8_t byteVal = 0;
  126.     
  127.    for ( uint8_t i = 0; i < 8; i++ )
  128.    {
  129.         byteVal >>= 1;
  130.        
  131.         uint8_t bitVal = readBit(); 
  132.         if( bitVal > 0)
  133.         {
  134.             byteVal |= 0x80;
  135.         }
  136.     }
  137.    
  138.     return  byteVal;
  139. }
  140.  
  141.  
  142. /**
  143.   * @brief  write one byte to DS18B20
  144.   * @note   
  145.   * @param  byte: the data that is sended to ds18b20
  146.   * @retval None
  147.   */
  148. void ds18b20WriteByte( uint8_t byte)
  149. {
  150.     unsigned char k;
  151.     
  152.     // Set PIN mode output
  153.     DS_Mode_Out_PP();
  154.     
  155.     for ( k = 0; k < 8; k++ )
  156.     {
  157.         if (byte & (1<<k))
  158.         {
  159.             DQ_SET_LOW;
  160.             timeDelayUS(2); 
  161.  
  162.             DQ_SET_HIGH;
  163.             timeDelayUS(65); 
  164.         }
  165.         else
  166.         {
  167.             DQ_SET_LOW;
  168.             timeDelayUS(65); 
  169.  
  170.             DQ_SET_HIGH;
  171.             timeDelayUS(2); 
  172.         }
  173.     }
  174. }
  175.  
  176. uint8_t ds18b20BlockModeProcess( void )
  177. {
  178.     uint16_t tempValue;
  179.     uint8_t tempL, tempH;
  180.  
  181.     if (ds18b20Init() == FALSE)
  182.     {
  183.         return FALSE;
  184.     }
  185.  
  186.     // wait for 600 us 
  187.     timeDelayUS(600);
  188.     
  189.     ds18b20WriteByte(0xcc);
  190.     ds18b20WriteByte(0x44);  // start convert temperature 
  191.  
  192.     if (ds18b20Init() == FALSE)
  193.     {
  194.         return FALSE;
  195.     }
  196.     // wait for 600 us 
  197.     timeDelayUS(600);
  198.  
  199.     ds18b20WriteByte(0xcc);
  200.     ds18b20WriteByte(0xbe);  // read temperature data register
  201.  
  202.     tempL = ds18b20ReadByte();
  203.     tempH = ds18b20ReadByte();
  204.     
  205.     if (tempH > 0x7f) 
  206.     {
  207.         tempL    = ~tempL;
  208.         tempH    = ~tempH+1; 
  209.         st_ds1b20val.sign = 1;
  210.     }
  211.  
  212.     tempValue = (uint16_t)((tempH << 8) | tempL);
  213.  
  214.     st_ds1b20val.temperatureVal = (float)(tempValue * 0.0625);
  215.     
  216.     return TRUE;
  217. }
  218.  
  219.  
  220. // NO blocking mode operate ds18b20 
  221. uint8_t ds18b20NoBlockingProcess( void )
  222. {
  223.     uint16_t tempValue;
  224.     static uint16_t waitCnt = 0;
  225.     uint8_t tempL, tempH;
  226.     static  uint8_t runState = 0;
  227.     
  228.     switch( runState )
  229.     {
  230.         default:
  231.         case INIT_DQ:
  232.             if (ds18b20Init() == FALSE)
  233.             {
  234.                 return FALSE;
  235.             }
  236.             runState = WAIT_READY;
  237.             break;
  238.             
  239.         case WAIT_READY:
  240.             timeDelayUS(2);       // IDEL 
  241.             runState = SKIDROM_CMD;
  242.             break;
  243.            
  244.        case SKIDROM_CMD:
  245.             ds18b20WriteByte(0xcc);
  246.             ds18b20WriteByte(0x44);  // begin to convert temperature data
  247.             waitCnt = 0;
  248.             runState = WAIT_CONVERT;
  249.             break;
  250.        
  251.        case WAIT_CONVERT:
  252.            waitCnt++;
  253.            if( waitCnt > WAIT_CNT_CONVERT)
  254.            {
  255.                waitCnt = 0;
  256.                runState = RESET_CMD;
  257.            }
  258.            break;
  259.         
  260.         case RESET_CMD:
  261.             if (ds18b20Init() == FALSE)
  262.             {
  263.                 return FALSE;
  264.             }
  265.             runState = WAIT_DATA_READY;
  266.             break;
  267.             
  268.         case WAIT_DATA_READY: 
  269.             timeDelayUS(2);     // IDEL 
  270.             runState = READ_CMD;
  271.             break;
  272.             
  273.         case READ_CMD:
  274.             ds18b20WriteByte(0xcc);
  275.             ds18b20WriteByte(0xbe);  // read temperature data register
  276.             runState = GET_VALUE;
  277.             break;
  278.             
  279.         case GET_VALUE:
  280.  
  281.             tempL = ds18b20ReadByte();
  282.             tempH = ds18b20ReadByte();
  283.  
  284.             if (tempH > 0x7f) 
  285.             {
  286.                 tempL    = ~tempL;
  287.                 tempH    = ~tempH+1; 
  288.                 st_ds1b20val.sign = 1;
  289.             }
  290.  
  291.             tempValue = (uint16_t)((tempH << 8) | tempL);
  292.  
  293.             st_ds1b20val.temperatureVal = (float)(tempValue * 0.0625);
  294.             runState = INIT_DQ;
  295.             return TRUE;
  296.     }
  297.     
  298.     return FALSE;
  299. }
  300.  
  301.  
  302.  
  303. /* End of this file */

2) Create the ds18b20.h file and write the following code

  1. /*
  2.     FILE NAME  :  ds18b20.h
  3.     Description:  user ds18b20 interface 
  4.     Author     :  [email protected]
  5.     Date       :  2024/06/03
  6. */
  7. #ifndef DS18B20_H
  8. #define DS18B20_H
  9. #include "hal_data.h"
  10.  
  11.  
  12. #define WAIT_CNT_CONVERT     500 
  13.  
  14. #define timeDelayUS(us)      R_BSP_SoftwareDelay(us, BSP_DELAY_UNITS_MICROSECONDS);
  15. #define DS_DELAY_MS(ms)      R_BSP_SoftwareDelay(ms, BSP_DELAY_UNITS_MILLISECONDS);
  16.  
  17.  
  18. #define DS_IO_PORT_PIN       BSP_IO_PORT_08_PIN_09
  19.  
  20.  
  21. #define DS_Mode_IN_PUT()     R_IOPORT_PinCfg(&g_ioport_ctrl, DS_IO_PORT_PIN, IOPORT_CFG_PORT_DIRECTION_INPUT)
  22. #define DS_Mode_Out_PP()     R_IOPORT_PinCfg(&g_ioport_ctrl, DS_IO_PORT_PIN, IOPORT_CFG_PORT_DIRECTION_OUTPUT)
  23.  
  24. #define DQ_SET_LOW           R_IOPORT_PinWrite(&g_ioport_ctrl, DS_IO_PORT_PIN, BSP_IO_LEVEL_LOW)
  25. #define DQ_SET_HIGH          R_IOPORT_PinWrite(&g_ioport_ctrl, DS_IO_PORT_PIN, BSP_IO_LEVEL_HIGH)
  26.  
  27.  
  28. typedef struct{
  29.     float  temperatureVal; 
  30.     bool sign;
  31. }ds18b20Struc;
  32.  
  33. uint8_t ds18b20BlockModeProcess( void );
  34. ds18b20Struc get_ds18b20_value( void );
  35.  
  36.  
  37. #endif   /* DS18B20_H */
  38.  
  39.

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