ads7870.h

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/*! \file ads7870.h \brief TI ADS7870 12-bit 8ch A/D Converter Driver Library. */
//*****************************************************************************
//
// File Name    : 'ads7870.h'
// Title        : TI ADS7870 12-bit 8ch A/D Converter Driver Library
// Author       : Pascal Stang - Copyright (C) 2005
// Created      : 2005.07.19
// Revised      : 2005.07.21
// Version      : 0.1
// Target MCU   : Atmel AVR Series
// Editor Tabs  : 4
//
// NOTE: This code is currently below version 1.0, and therefore is considered
// to be lacking in some functionality or documentation, or may not be fully
// tested.  Nonetheless, you can expect most functions to work.
//
// This code is distributed under the GNU Public License
//      which can be found at http://www.gnu.org/licenses/gpl.txt
//
/// \ingroup driver_hw
/// \defgroup ads7870 TI ADS7870 SPI A/D Converter Driver (ads7870.c)
/// \code #include "ads7870.h" \endcode
/// \par Overview
///     This library provides high-level functions for accessing the Texas
///     Instruments ADS7870 I2C A/D Converter.
///
///     The basic specs of the ADS7870 are:
///     - Fast SPI interface (up to 20MHz)
///     - 12-bit results
///     - 8 single-ended or 4 differential input channels
///     - Programmable gain stage (1,2,4,5,8,10,16,20x gains)
///     - Software or hardware triggered conversion
///     - 4-bit auxiliary digital I/O lines (controlled via serial interface)
///     - Up to 50KHz conversion rate
///     - External reference or internal 2.5V, 2.048V, 1.15V reference
///     - NOTE: use pin-compatible ADS7871 for 14-bit results
//
//*****************************************************************************
//@{

#ifndef ADS7870_H
#define ADS7870_H

#include "global.h"

// constants/macros/typdefs
#define ADS7870_CS_PORT         PORTB
#define ADS7870_CS_DDR          DDRB
#define ADS7870_CS_PIN          PB0

// instruction bit defines
#define ADS7870_CONVERT         0x80

#define ADS7870_REG_READ        0x40
#define ADS7870_REG_WRITE       0x00
#define ADS7870_REG_16BIT       0x20

// register addresses
#define ADS7870_RESULTLO        0x00
#define ADS7870_RESULTHI        0x01
#define ADS7870_PGAVALID        0x02
#define ADS7870_ADCTRL          0x03
#define ADS7870_GAINMUX         0x04
#define ADS7870_DIGIOSTATE      0x05
#define ADS7870_DIGIOCTRL       0x06
#define ADS7870_REFOSC          0x07
#define ADS7870_SERIFCTRL       0x18
#define ADS7870_ID              0x1F

// register bit defines
#define ADS7870_RESULTLO_OVR    0x01

#define ADS7870_ADCTRL_BIN      0x20
#define ADS7870_ADCTRL_RMB1     0x08
#define ADS7870_ADCTRL_RMB0     0x04
#define ADS7870_ADCTRL_CFD1     0x02
#define ADS7870_ADCTRL_CFD0     0x01

#define ADS7870_GAINMUX_CNVBSY  0x80

#define ADS7870_REFOSC_OSCR     0x20
#define ADS7870_REFOSC_OSCE     0x10
#define ADS7870_REFOSC_REFE     0x08
#define ADS7870_REFOSC_BUFE     0x04
#define ADS7870_REFOSC_R2V      0x02
#define ADS7870_REFOSC_RBG      0x01

#define ADS7870_SERIFCTRL_LSB   0x01
#define ADS7870_SERIFCTRL_2W3W  0x02
#define ADS7870_SERIFCTRL_8051  0x04

#define ADS7870_ID_VALUE        0x01

// gain defines
#define ADS7870_GAIN_1X         0x00
#define ADS7870_GAIN_2X         0x10
#define ADS7870_GAIN_4X         0x20
#define ADS7870_GAIN_5X         0x30
#define ADS7870_GAIN_8X         0x40
#define ADS7870_GAIN_10X        0x50
#define ADS7870_GAIN_16X        0x60
#define ADS7870_GAIN_20X        0x70
// channel defines
#define ADS7870_CH_0_1_DIFF     0x00
#define ADS7870_CH_2_3_DIFF     0x01
#define ADS7870_CH_4_5_DIFF     0x02
#define ADS7870_CH_6_7_DIFF     0x03
#define ADS7870_CH_1_0_DIFF     0x04
#define ADS7870_CH_3_2_DIFF     0x05
#define ADS7870_CH_5_4_DIFF     0x06
#define ADS7870_CH_7_6_DIFF     0x07
#define ADS7870_CH_SINGLE_ENDED 0x08
#define ADS7870_CH_0            0x08
#define ADS7870_CH_1            0x09
#define ADS7870_CH_2            0x0A
#define ADS7870_CH_3            0x0B
#define ADS7870_CH_4            0x0C
#define ADS7870_CH_5            0x0D
#define ADS7870_CH_6            0x0E
#define ADS7870_CH_7            0x0F

// functions

//! Initialize the ADS7870 chip.
/// Returns:
/// TRUE if successful, 
/// FALSE if unsuccessful (chip not responding).
u08 ads7870Init(void);

//! Begin single-ended conversion on given logical channel#0-7, and return result.
/// \note Result is returned left-justified.
s16 ads7870Convert(u08 channel);

//! Begin differential conversion on given channel pair, and return result.
/// \note Result is returned left-justified.
s16 ads7870ConvertDiff(u08 channel);

//! Begin conversion on given raw channel#, and return result.
/// \note Result is returned left-justified.
s16 ads7870ConvertRaw(u08 channel);

//! Read value from ADS7870 register.
///
u08 ads7870ReadReg(u08 reg);

//! Write value into ADS7870 register.
///
void ads7870WriteReg(u08 reg, u08 value);



#endif
//@}

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