AD5790-微控制器无操作系统驱动程序

消耗积分:2 | 格式:pdf | 大小:1.37MB | 2021-05-22

王磊

分享资料个

This version (24 Jan 2021 17:21) was approved by Dragos Bogdan.The Previously approved version (24 Jan 2021 17:07) is available.

AD5790 - Microcontroller No-OS Driver

Supported Devices

AD5790

Evaluation Boards

EVAL-AD5790SDZ

Reference Circuits

CN0257

Overview

The AD5790 is a single 20-bit, voltage out Dac that operates from a bipolar supply up to 33V. Reference buffers are also provided on-chip The AD5790 accepts a positive reference input in the range of 5V to VDD – 2.5V and a negative reference input in the range of VSS + 2.5v to 0V. The AD5790 offers a relative accuracy of +/-2 LSB's max and operation is guaranteed monotonic with a -1 LSB to +3 LSB's DNL specification. The part uses a versatile 3-wire serial interface that operates at clock rates up to 35 MHz and is compatible with standard SPI®, QSPI™, MICROWIRE™, and DSP interface standards. The part incorporates a power-on reset circuit that ensures the DAC output powers up to 0V and in a known output impedance state and remains in this state until a valid write to the device takes place. The part provides a disable feature that places the output in a defined load state.

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.

HW Platform(s):

Renesas Demo Kit for RL78G13 (Renesas)

Driver Description

The driver contains two parts:

The driver for the AD5790 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 AD5790 driver can be used exactly as it is provided.

There are three functions which are called by the AD5790 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 AD5790 driver:

Function	Description
unsigned char AD5790_Init(void)	Initialize the communication with the device.
void AD5790_EnableOutput(unsigned char state)	The part is placed in normal mode or its output is clamped to the ground.
void AD5790_SetRegisterValue(unsigned char registerAddress, unsigned long registerValue, unsigned char bytesNumber)	Writes data into a register.
unsigned long AD5790_GetRegisterValue(unsigned char registerAddress, unsigned char bytesNumber)	Reads the value of a register.
void AD5790_SetDacValue(unsigned long value)	Writes to the DAC register.
void AD5790_SoftInstruction(unsigned char instructionBit)	Asserts RESET, CLR and LDAC in a software manner.
void AD5790_Setup(unsigned long setupWord)	Writes to Control Register.

Downloads

Renesas RL78G13 Quick Start Guide

This section contains a description of the steps required to run the AD5790 demonstration project on a Renesas RL78G13 platform.

Required Hardware

Required Software

Hardware Setup

An EVAL-AD5790SDZ has to be interfaced with the Renesas Demonstration Kit (RDK) for RL78G13:

  EVAL-AD5790SDZ J3 connector Pin SYNC  (CS)     → YRDKRL78G13 J11 connector Pin 1
  EVAL-AD5790SDZ J3 connector Pin SDIN  (MOSI)   → YRDKRL78G13 J11 connector Pin 2
  EVAL-AD5790SDZ J3 connector Pin SDO   (MISO)   → YRDKRL78G13 J11 connector Pin 3
  EVAL-AD5790SDZ J3 connector Pin SCLK  (SCLK)   → YRDKRL78G13 J11 connector Pin 4
  EVAL-AD5790SDZ J3 connector Pin DGND  (DGND)   → YRDKRL78G13 J11 connector Pin 5
  EVAL-AD5790SDZ J3 connector Pin LDAC  (LDAC)   → YRDKRL78G13 J11 connector Pin 9  
  EVAL-AD5790SDZ J3 connector Pin CLR   (CLR)    → YRDKRL78G13 J11 connector Pin 10
  EVAL-AD5790SDZ J3 connector Pin RESET (Reset)  → YRDKRL78G13 J18 connector Pin 30

Software Setup

With the Applilet3 for RL78G13 tool the following peripherals have to be configured:

CSI10 (Clocked Serial Interface 10) – For the AD5790 part and the ST7579 LCD

Choose to generate the Transmit/receive function for the CSI10 and configure the interface with the following settings:

Transfer mode setting: Single transfer mode
Data length setting : 8 bits
Transfer direction setting: MSB
Specification of data timing: Type 3
Transfer rate setting – Clock mode: Internal clock (master)
Transfer rate setting – Baudrate: 1000000 (bps)
Interrupt setting – Transfer interrupt priority (INTCSI10): Low
Uncheck the callback functions.

TM00 (Timer 00) – For the DelayMs() function

Configure TM00 as an interval timer:

Interval timer setting - Interval value(16 bits): 1 ms
Interval timer setting - Uncheck Generates INTM00 when counting is started
Interrupt setting - Uncheck End of timer channel 0 count, generate an interrupt (INTM00)

Watchdog Timer

Disable the watchdog timer:

Choose for the Watchdog timer operation setting: Unused option.

Reference Project Overview

The reference project initializes the device, reads the parts internal registers, displays them and then generates a triangle signal.

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.

Two software applications have to be used: Applilet3 for RL78G13 (a tool that automatically generates device drivers for MCU peripheral functions) and IAR Embedded Workbench for Renesas RL78 (the integrated development environment).

Step 1 - Applilet3 for RL78G13

Run the Applilet3 for RL78G13 tool and create a new project for R5F100LE processor. Select IAR Compiler build tool, a project name, a location for the new project and press OK.

Keep the default Pin assignment setting and click Fix settings.

Now the desired peripherals can be configured and the code can be generated. For example, if the clocked serial interface 10 (CSI10) has to be configured, select the Serial peripheral, choose for the Channel 2 of Serial Array Unit 0 (SAU0) the CSI10 interface, Transmit/receive function option and then go to CSI10 tab.

To configure the CSI10 interface for serial transmissions of 8 bits, with MSB first, with the data captured on clock's rising edge, with a frequency of the clock of 1 MHz and the idle state high, the settings from the following image have to be made.

After all the desired peripherals are configured click on the Generate Code button and a new workspace and a new project for the IAR Embedded Workbench will be generated. After the code was generated close the Applilet3 for RL78G13 tool.

Step 2 - IAR Embedded Workbench for Renesas RL78

Run the IAR Embedded Workbench and open the workspace created with the Applilet3 tool.

Copy the files extracted from the zip file into the user_src folder, located in the project’s folder.

The new source files have to be included into the project. Add in the user_src group the files from the corresponding folder (Right click on the group and select Add – Add Files…). Because a new Main file was included the r_main.c file from the applilet_src group has to be deleted (Right click on the file and select Remove).

Now the debugger driver has to be selected from the project’s options. Right click on the project name and select Options. From the Debugger category choose the TK Debugger Driver.

Now, 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.

29 Feb 2012 17:01 · Dragos Bogdan