HPADDAlibrary

C Library for High-Precision AD/DA Board

This library includes High-Precision AD/DA Board official files(https://www.waveshare.com/wiki/File:High-Precision-AD-DA-Board-Code.7z). I got permission from an administrator of the official for publication.

Required

• Hardware
  • Raspberry Pi
  • High-Precision AD/DA Board
• Library
  • bcm2835 library

Usage

cd ./HPADDAlibrary
make
sudo ./Test

Functions

Use for both AD and DA

int initHPADDAboard()

• function: init ADS1256 & DAC8532
• parameter: NULL
• The return value: 0:successful 1:Abnormal

void closeHPADDAboard()

• function: close SPI, ADS1256 & DAC8532
• parameter: NULL
• The return value: NULL

void delay_us(uint64_t micros)

• function: wait[us]
• parameter:
  • [us]
• The return value: NULL

Use for DA

void DAC8532_Write( int dac_channel , unsigned int val)

• function: change an output of DAC8532 to target value
• parameter:
  • dac_channel : channel of DAC8532 (0 or 1)
  • val : output value to DAC8532 ( 0 - 65536 ) , please use DAC8532_VoltToValue function
• The return value: NULL

unsigned int DAC8532_VoltToValue( double volt , double volt_ref)

• function: convert value from volt to 16bit value ( 0 - 65535 )
• parameter: volt : target volt [v] ( 0 - 5.0 )
  • volt_ref : reference volt [v] ( 3.3 or 5.0 )
• The return value: output value to DAC8532 ( 0 - 65535 )

Use for AD

int32_t ADS1256_GetAdc(uint8_t _ch);

• function: read ADC value
• parameter:
  • channel number 0--7
• The return value: ADC vaule (signed number)

int32_t ADS1256_GetAdcDiff(uint8_t positive_no , uint8_t negative_no );

• function: read ADC value
• parameter:
  • positive_no : input port no of positive side (0 - 7)
  • negative_no : input port no of negative side (0 - 7)
• The return value: ADC vaule (signed number)

double ADS1256_ValueToVolt(uint32_t value , double vref);

• function: convert ADC output value to volt [V]
• parameter:
  • value : output value ( 0 - 0x7fffff )
  • reference voltage [V] ( 3.3 or 5.0 )
• The return value: ADC voltage [V]

Use for AD (Print)

void ADS1256_PrintAllValue();

• function: print 8 values of ADS1256 input
• parameter: NULL
• The return value: NULL

void ADS1256_PrintAllValueDiff();

• name: ADS1256_PrintAllValueDiff
• function: print 4 values of ADS1256 differential input
• parameter: NULL
• The return value: NULL

void ADS1256_PrintAllReg();

• function: print all register of ADS1256
• parameter: NULL
• The return value: NULL

Use for AD (Settings)

double ADS1256_SetSampleRate(double rate)

• function: set sampling rate of ADS1256
• parameter:
  • rate : [samples per second] (2.5 - 30000)
    • This rate is for one input. It becomes later in the case of multi input.
• The return value: Actual set value

int ADS1256_SetGain(int gain)

• function: set Gain of ADS1256
• parameter:
  • rate : Gain (1 - 64)
• The return value: Actual set value

uint8_t ADS1256_ReadChipID(void);

• function: Read the chip ID
• parameter:
  • _cmd : NULL
• The return value: four high status register

static void ADS1256_WriteReg(uint8_t _RegID, uint8_t _RegValue);

• function: Write the corresponding register
• parameter:
  • _RegID: register ID
  • _RegValue: register Value
• The return value: NULL

static uint8_t ADS1256_ReadReg(uint8_t _RegID);

• function: Read the corresponding register
• parameter:
  • _RegID: register ID
• The return value: read register value

static void ADS1256_WriteCmd(uint8_t _cmd);

• function: Sending a single byte order
• parameter:
  • _cmd : command
• The return value: NULL

Use for AD (Private Functions)

void setCS_DAC8532(char b)

• function: set SPI CS pin value of DAC8532
• parameter:
  • b : bool value for SPI CS status (0 : connection start , 1: connection end)
• The return value: NULL

static int32_t ADS1256_ReadData(void);

• function: read ADC value
• parameter: NULL
• The return value: NULL

static void ADS1256_DelayDATA(void);

• function: delay
• parameter: NULL
• The return value: NULL

void ADS1256_WaitDRDY(void);

• function: delay time wait for automatic calibration
• parameter: NULL
• The return value: NULL

void ADS1256_ChangeMUX(int8_t positive_no , int8_t negative_no );

• function: set ADS1256 MUX for changing input of ADC
• parameter:
  • positive_no :input port no of positive side (0 - 7 or -1) * Nomally it should be set to 0 - 7. When set to -1 , AGND becomes positive input.
  • negative_no :input port no of negative side (-1 or 0 - 7) * Nomally it should be set to -1. When use Differential Input, it should be set to 0 - 7.
• The return value: NULL

void ADS1256_SetCS(char b);

• function: set SPI CS pin value of ADS1256
• parameter:
  • b : bool value for SPI CS status (0 : connection start , 1: connection end)
• The return value: NULL

static void ADS1256_Send8Bit(uint8_t _data);

• function: SPI bus to send 8 bit data
• parameter:
  • _data: data
• The return value: NULL

static uint8_t ADS1256_Recive8Bit(void);

• function: SPI bus receive function
• parameter: NULL
• The return value: NULL