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This version (08 May 2013 13:50) was approved by DNechita.The Previously approved version (15 Nov 2012 18:23) is available.Diff

AD7190 - Microcontroller No-OS Driver

Supported Devices

Evaluation Boards

Overview

The AD7190, AD7192 and AD7195 are low noise, complete analog front ends for high precision measurement applications. Devices contain a low noise, 24-bit sigma-delta (Σ-Δ) analog-to-digital converter (ADC). The on-chip low noise gain stage means that signals of small amplitude can be interfaced directly to the ADC. The AD7195 contains ac excitation, which is used to remove dc-induced offsets from bridge sensors.

Devices can be configured to have two differential inputs or four pseudo differential inputs. The on-chip channel sequencer allows several channels to be enabled, and the AD7190, AD7192 and AD7195 sequentially convert on each enabled channel. This simplifies communication with the parts. The on-chip 4.92 MHz clock can be used as the clock source to the ADC or, alternatively, an external clock or crystal can be used. The output data rate from the parts can be varied from 4.7 Hz to 4.8 kHz.

The goal of this project (Microcontroller No-OS) is to be able to provide reference projects for lower end processors, which can't run Linux, or aren't running a specific operating system, to help those customers using microcontrollers with ADI parts. Here you can find a generic driver which can be used as a base for any microcontroller platform and also specific drivers for Renesas platforms.

Driver Description

The driver contains two parts:

  • The driver for the AD7190 part, which may be used, without modifications, with any microcontroller.
  • The Communication Driver, where the specific communication functions for the desired type of processor and communication protocol have to be implemented. This driver implements the communication with the device and hides the actual details of the communication protocol to the ADI driver.

The Communication Driver has a standard interface, so the AD7190 driver can be used exactly as it is provided.

There are three functions which are called by the AD7190 driver:

  • SPI_Init() – initializes the communication peripheral.
  • SPI_Write() – writes data to the device.
  • SPI_Read() – reads data from the device.

SPI driver architecture

The following functions are implemented in this version of AD7190 driver:

Function Description
void AD7190_SetRegisterValue(unsigned char registerAddress, unsigned long registerValue, unsigned char bytesNumber, unsigned char modifyCS) Writes data into a register.
unsigned long AD7190_GetRegisterValue(unsigned char registerAddress, unsigned char bytesNumber, unsigned char modifyCS) Reads the value of a register.
unsigned char AD7190_Init(void) Initializes the SPI peripheral and checks if the AD7190 part is present.
void AD7190_Reset(void) Resets the device.
void AD7190_SetPower(unsigned char pwrMode) Set device to idle or power-down.
void AD7190_WaitRdyGoLow(void) Waits for RDY pin to go low.
void AD7190_ChannelSelect(unsigned short channel) Selects the channel to be enabled.
void AD7190_Calibrate(unsigned char mode, unsigned char channel) Performs the given calibration to the specified channel.
void AD7190_RangeSetup(unsigned char polarity, unsigned char range) Selects the polarity of the conversion and the ADC input range.
unsigned long AD7190_SingleConversion(void) Returns the result of a single conversion.
unsigned long AD7190_ContinuousReadAvg(unsigned char sampleNumber) Returns the average of several conversion results.
unsigned long AD7190_TemperatureRead(void) Read data from temperature sensor and converts it to Celsius degrees.

HW Platform(s):

Downloads

Renesas RL78G13 Quick Start Guide

This section contains a description of the steps required to run the AD7190 demonstration project on a Renesas RL78G13 platform.

Required Hardware

Required Software

Hardware Setup

An EVAL-AD7190EBZ has to be interfaced with the Renesas Demonstration Kit (RDK) for RL78G13:

  EVAL-AD7190EBZ J2 connector Pin CS      →  YRDKRL78G13 J11 connector Pin 1
  EVAL-AD7190EBZ J2 connector Pin DIN     →  YRDKRL78G13 J11 connector Pin 2
  EVAL-AD7190EBZ J2 connector Pin DOUT    →  YRDKRL78G13 J11 connector Pin 3
  EVAL-AD7190EBZ J2 connector Pin SCLK    →  YRDKRL78G13 J11 connector Pin 4
  EVAL-AD7190EBZ J2 connector Pin AGND    →  YRDKRL78G13 J11 connector Pin 5
  

Reference Project Overview

The reference project:

  • checks if the AD7190 part is present;
  • configures the AD7190 part;
  • reads data from single conversion;
  • reads data from multiple conversions, calculates the average value and displays it;
  • reads data from the temperature sensor and displays it in degrees Celsius.

Software Project Setup

This section presents the steps for developing a software application that will run on the Renesas Demo Kit for RL78G13 for controlling and monitoring the operation of the ADI part.

  • Run the IAR Embedded Workbench for Renesas RL78 integrated development environment.
  • Choose to create a new project (Project – Create New Project).
  • Select the RL78 tool chain, the Empty project template and click OK.

  • Select a location and a name for the project (ADIEvalBoard for example) and click Save.

  • Open the project’s options window (Project – Options).
  • From the Target tab of the General Options category select the RL78 – R5F100LE device.

  • From the Setup tab of the Debugger category select the TK driver and click OK.

  • Extract the files from the lab .zip archive and copy them into the project’s folder.

  • The new source files have to be included into the project. Open the Add Files… window (Project – Add Files…), select all the copied files and click open.

  • At this moment, all the files are included into the project.
  • The project is ready to be compiled and downloaded on the board. Press the F7 key to compile it. Press CTRL + D to download and debug the project.
  • A window will appear asking to configure the emulator. Keep the default settings and press OK.

  • To run the project press F5.

03 Sep 2012 13:02 · Dragos Bogdan

Renesas RX62N Quick Start Guide

This section contains a description of the steps required to run the AD7190 demonstration project on a Renesas RX62N platform.

Required Hardware

Required Software

Hardware Setup

An EVAL-AD7190EBZ board has to be interfaced with the Renesas Demonstration Kit (RDK) for RX62N:

  EVAL-AD7190EBZ J2 connector Pin CS      →  YRDKRX62N J8 connector Pin 15
  EVAL-AD7190EBZ J2 connector Pin DIN     →  YRDKRX62N J8 connector Pin 19
  EVAL-AD7190EBZ J2 connector Pin DOUT    →  YRDKRX62N J8 connector Pin 22
  EVAL-AD7190EBZ J2 connector Pin SCLK    →  YRDKRX62N J8 connector Pin 20
  EVAL-AD7190EBZ J2 connector Pin AGND    →  YRDKRX62N J8 connector Pin 4

Reference Project Overview

The reference project:

  • checks if the AD7190 part is present;
  • configures the AD7190 part;
  • reads data from single conversion;
  • reads data from multiple conversions, calculates the average value and displays it;
  • reads data from the temperature sensor and displays it in degrees Celsius.

Software Project Setup

This section presents the steps for developing a software application that will run on the Renesas Demo Kit for RX62N for controlling and monitoring the operation of the ADI part.

  • Run the High-performance Embedded Workshop integrated development environment.
  • A window will appear asking to create or open project workspace. Choose “Create a new project workspace” option and press OK.
  • From “Project Types” option select “Application”, name the Workspace and the Project “ADIEvalBoard”, select the “RX” CPU family and “Renesas RX Standard” tool chain. Press OK.

  • A few windows will appear asking to configure the project:
    • In the ”Select Target CPU” window, select “RX600” CPU series, “RX62N” CPU Type and press Next.
    • In the “Option Setting” windows keep default settings and press Next.
    • In the “Setting the Content of Files to be generated” window select ”None” for the ”Generate main() Function” option and press Next.
    • In the “Setting the Standard Library” window press “Disable all” and then Next.
    • In the “Setting the Stack Area” window check the ”Use User Stack” option and press Next.
    • In the “Setting the Vector” window keep default settings and press Next.
    • In the “Setting the Target System for Debugging” window choose “RX600 Segger J-Link” target and press Next.
    • In the “Setting the Debugger Options” and “Changing the Files Name to be created” windows keep default settings, press Next and Finish.
  • The workspace is created.

  • The RPDL (Renesas Peripheral Driver Library) has to integrated in the project. Unzip the RPDL files (double-click on the file “RPDL_RX62N.exe”). Navigate to where the RPDL files were unpacked and double-click on the “Copy_RPDL_RX62N.bat” to start the copy process. Choose the LQFP package, type the full path where the project was created and after the files were copied, press any key to close the window.
  • The new source files have to be included in the project. Use the key sequence Alt, P, A to open the “Add files to project ‘ADIEvalBoard’” window. Double click on the RPDL folder. From the “Files of type” drop-down list, select “C source file (*.C)”. Select all of the files and press Add.

  • To avoid conflicts with standard project files remove the files “intprg.c” and “vecttbl.c” which are included in the project. Use the key sequence Alt, P, R to open the “Remove Project Files” window. Select the files, click on Remove and press OK.

  • Next the new directory has to be included in the project. Use the key sequence Alt, B, R to open the “RX Standard Toolchain” window. Select the C/C++ tab, select “Show entries for: Include file directories” and press Add. Select “Relative to: Project directory”, type “RPDL” as sub-directory and press OK.

  • The library file path has to be added in the project. Select the Link/Library tab, select “Show entries for: Library files” and press Add. Select “Relative to: Project directory”, type “RPDL\RX62N_library” as file path and press OK.

  • Because the “intprg.c” file was removed the “PIntPrg” specified in option “start” has to be removed. Change “Category” to “Section”. Press ”Edit”, select “PIntPRG” and press “Remove”. From this window the address of each section can be also modified. After all the changes are made press OK two times.

  • At this point the files extracted from the zip file located in the “Software Tools” section have to be added into the project. Copy all the files from the archive into the project folder.

  • Now, the files have to be included in the project. Use the key sequence Alt, P, A to open the “Add files to project ‘ADIEvalBoard’” window. Navigate into ADI folder. From the “Files of type” drop-down list, select “Project Files”. Select all the copied files and press Add.

  • Now, the project is ready to be built. Press F7. The message after the Build Process is finished has to be “0 Errors, 0 Warnings”. To run the program on the board, you have to download the firmware into the microprocessor’s memory.
03 Feb 2012 15:32 · Dragos Bogdan

More information

01 Jun 2012 12:21