Analog Devices / AD5270

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Dependents:   ad5270-helloworld CN0357 CN0396

Embed: (wiki syntax)

« Back to documentation index

AD5270 Class Reference
Public Types | Public Member Functions | Data Fields

AD5270 Class Reference

Analog Devices AD5270 SPI Digital Rheostat class. More...

#include <AD5270.h>

Public Types

enum  AD5270Commands_t {
  NO_OP = 0x00, NO_OP_cmd = 0x0000, WRITE_RDAC = 0x04, READ_RDAC = 0x08,
  STORE_50TP = 0x0C, SW_RST = 0x10, READ_50TP_CONTENTS = 0x14, READ_50TP_ADDRESS = 0x18,
  WRITE_CTRL_REG = 0x1C, READ_CTRL_REG = 0x20, SW_SHUTDOWN = 0x24, HI_Zupper = 0x80,
  HI_Zlower = 0x01, HI_Z_Cmd = 0x8001
}
 

AD5270 commands.

More...

Public Member Functions

 AD5270 (PinName CS=SPI_CS, float max_resistance=20000.0, PinName MOSI=SPI_MOSI, PinName MISO=SPI_MISO, PinName SCK=SPI_SCK)
 AD5270 constructor, sets CS pin and SPI format.
void frequency (int hz)
 Set AD5270 SPI frequency.
void write_ctrl_reg (uint8_t data)
 Writes the control register.
uint8_t read_ctrl_reg (void)
 Reads the control register.
void change_mode (AD5270Modes_t mode)
 Changes the device mode, enabled or shutdown.
void set_SDO_HiZ (void)
 Puts the AD5270 SDO line in to Hi-Z mode.
void reset_RDAC (void)
 Resets the wiper register value to the data last written in the 50TP.
void write_wiper_reg (uint16_t data)
 Writes the wiper register.
uint16_t read_wiper_reg (void)
 Reads the wiper register value.
uint16_t write_cmd (uint8_t command, uint16_t data=0x00, bool toggle_cs=true)
 Issues AD5270 a command.
uint16_t write_reg (uint16_t data, bool toggle_cs=true)
 Writes 16bit data to the AD5270 SPI interface.
uint16_t calc_RDAC (float resistance)
 Compute for the nearest RDAC value from given resistance.
float write_RDAC (float resistance)
 sets a new value for the RDAC
float read_RDAC (void)
 Reads the RDAC register.
float get_max_resistance (void)
 Gets maximum resistance of the AD5270 digital rheostat.
void enable_50TP_programming (void)
 Enables the 50TP memory programming.
void store_50TP (void)
 Stores current RDAC content to the 50TP memory.
void disable_50TP_programming (void)
 Disables the 50TP memory programming.
uint8_t read_50TP_last_address (void)
 Reads the last programmed value of the 50TP memory.
uint16_t read_50TP_memory (uint8_t address)
 Reads the content of a 50TP memory address.

Data Fields

SPI ad5270
 SPI instance of the AD5270.
DigitalOut cs
 DigitalOut instance for the chip select of the AD5270.

Detailed Description

Analog Devices AD5270 SPI Digital Rheostat class.

Definition at line 56 of file AD5270.h.

Member Enumeration Documentation

enum AD5270Commands_t

AD5270 commands.

Enumerator:
NO_OP 

No data.

NO_OP_cmd 

16 bit no data

WRITE_RDAC 

Write to the RDAC Register.

READ_RDAC 

Read from the RDAC Register.

STORE_50TP 

Write from RDAC to memory.

SW_RST 

Software reset to last memory location.

READ_50TP_CONTENTS 

Read the last memory contents.

READ_50TP_ADDRESS 

Read the last memory address.

WRITE_CTRL_REG 

Write to the control Register.

READ_CTRL_REG 

Read from the control Register.

SW_SHUTDOWN 

Software shutdown (0) - Normal, (1) - Shutdown.

HI_Zupper 

Get the SDO line ready for High Z.

HI_Zlower 

Puts AD5270 into High Z mode.

HI_Z_Cmd 

Puts AD5270 into High Z mode*/.

Definition at line 61 of file AD5270.h.

Constructor & Destructor Documentation

AD5270 ( PinName  CS = SPI_CS,
float  max_resistance = 20000.0,
PinName  MOSI = SPI_MOSI,
PinName  MISO = SPI_MISO,
PinName  SCK = SPI_SCK 
)

AD5270 constructor, sets CS pin and SPI format.

Parameters:
CS- (optional)chip select of the AD5270
max_resistance- (optional) nominal resistance of the AD5270 chip in ohms
MOSI- (optional)pin of the SPI interface
MISO- (optional)pin of the SPI interface
SCK- (optional)pin of the SPI interface

Definition at line 60 of file AD5270.cpp.

Member Function Documentation

uint16_t calc_RDAC ( float  resistance )

Compute for the nearest RDAC value from given resistance.

Parameters:
resistance- resistor
Returns:
RDAC value - closest possible to given resistance

Definition at line 72 of file AD5270.cpp.

void change_mode ( AD5270Modes_t  mode )

Changes the device mode, enabled or shutdown.

Parameters:
mode- new mode of the device

Definition at line 277 of file AD5270.cpp.

void disable_50TP_programming ( void   )

Disables the 50TP memory programming.

Definition at line 156 of file AD5270.cpp.

void enable_50TP_programming ( void   )

Enables the 50TP memory programming.

Definition at line 138 of file AD5270.cpp.

void frequency ( int  hz )

Set AD5270 SPI frequency.

Parameters:
hz- SPI bus frequency in hz
Returns:
none

Definition at line 117 of file AD5270.cpp.

float get_max_resistance ( void   )

Gets maximum resistance of the AD5270 digital rheostat.

Returns:
maximum resistance in ohms

Definition at line 184 of file AD5270.cpp.

uint8_t read_50TP_last_address ( void   )

Reads the last programmed value of the 50TP memory.

Returns:
last programmed value

Definition at line 220 of file AD5270.cpp.

uint16_t read_50TP_memory ( uint8_t  address )

Reads the content of a 50TP memory address.

Parameters:
addressmemory to be read
Returns:
value stored in the 50TP address

Definition at line 234 of file AD5270.cpp.

uint8_t read_ctrl_reg ( void   )

Reads the control register.

Returns:
value of the control register

Definition at line 256 of file AD5270.cpp.

float read_RDAC ( void   )

Reads the RDAC register.

Returns:
RDAC resistor value

Definition at line 95 of file AD5270.cpp.

uint16_t read_wiper_reg ( void   )

Reads the wiper register value.

Returns:
value of the wiper register

Definition at line 207 of file AD5270.cpp.

void reset_RDAC ( void   )

Resets the wiper register value to the data last written in the 50TP.

Definition at line 268 of file AD5270.cpp.

void set_SDO_HiZ ( void   )

Puts the AD5270 SDO line in to Hi-Z mode.

Returns:
none

Definition at line 105 of file AD5270.cpp.

void store_50TP ( void   )

Stores current RDAC content to the 50TP memory.

Definition at line 147 of file AD5270.cpp.

uint16_t write_cmd ( uint8_t  command,
uint16_t  data = 0x00,
bool  toggle_cs = true 
)

Issues AD5270 a command.

Parameters:
command- command to be sent
data- (optional)value for the requested command
Returns:
response form the AD5270

Definition at line 128 of file AD5270.cpp.

void write_ctrl_reg ( uint8_t  data )

Writes the control register.

Parameters:
datato be written

Definition at line 247 of file AD5270.cpp.

float write_RDAC ( float  resistance )

sets a new value for the RDAC

Parameters:
resistancenew value for the resistance
Returns:
actual value of the resistance in the RDAC

Definition at line 82 of file AD5270.cpp.

uint16_t write_reg ( uint16_t  data,
bool  toggle_cs = true 
)

Writes 16bit data to the AD5270 SPI interface.

Parameters:
datato be written
Returns:
data returned by the AD5270

Definition at line 167 of file AD5270.cpp.

void write_wiper_reg ( uint16_t  data )

Writes the wiper register.

This includes reading the control register, setting write protect off, writing the wiper, and reverting the settings to the control reg.

Parameters:
datato be written

Definition at line 195 of file AD5270.cpp.

Field Documentation

SPI ad5270

SPI instance of the AD5270.

Definition at line 125 of file AD5270.h.

DigitalOut cs

DigitalOut instance for the chip select of the AD5270.

Definition at line 126 of file AD5270.h.

Generated on Wed Jul 13 2022 06:13:55 by  doxygen 1.7.2