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akaka
Joined: 18 Jul 2012
Posts: 14
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| Interfacing AD7730 |
 Posted: Sat Feb 27, 2016 4:54 am |
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Hi every one I was looking for any similar post for days.....
I want to interface AD7730 Bridge Transducer ADC with a PIC.
The project it is still in Demo Mode and it's simple in main loop.
So here is the schematic
http://postimg.org/image/d77oqkcxt/
and code follows:
Libraries for AD7730
AD7730.c
| Code: | /*----------------------------------------------------------------------------
File: AD7730.c
Description
Driver of AD7730
Project : Operating System for 16f88---->Test weighing scale with AD7730
Created for Version: 1.0
Updated for Version: 1.0
Last Date Modified : 20/02/2016
Copyright(c) 2016 by Chris_Kal
All Rights Reserved.
----------------------------------------------------------------------------*/
#include "AD7730.h"
#define RESET PIN_B6
#define READY PIN_B5
#define AD7730_SELECT PIN_B3
void SendAD_Data(BYTE data)
{
//delay_ms(2);
spi_write(data);
//delay_ms(5);
}
void AD7730_Init()
{
//-----------Filter Configuration-------------------------------
printf("Filter Configuration...\r\n");
output_low(AD7730_SELECT);
SendAD_Data(CR_SINGLE_WRITE | CR_FILTER_REGISTER);
SendAD_Data(FR2_SINC_AVERAGING_2048);
SendAD_Data(FR1_SKIP_OFF | FR1_FAST_OFF);
SendAD_Data(FR0_CHOP_ON);
output_high(AD7730_SELECT);
//--------------------------------------------------------------
delay_ms(30);
//----------------DAC Configuration-----------------------------
printf("DAC Configuration...\r\n");
output_low(AD7730_SELECT);
SendAD_Data(CR_SINGLE_WRITE | CR_DAC_REGISTER);
SendAD_Data(DACR_OFFSET_SIGN_POSITIVE | DACR_OFFSET_NONE);
output_high(AD7730_SELECT);
//--------------------------------------------------------------
delay_ms(30);
//---------Internal Zero Calibartion----------------------------
printf("Internal Zero Calibartion...\r\n");
output_low(AD7730_SELECT);
SendAD_Data(CR_SINGLE_WRITE | CR_MODE_REGISTER);
SendAD_Data(MR1_MODE_INTERNAL_ZERO_CALIBRATION | CURRENT_MODE_1_SETTINGS);
SendAD_Data(CURRENT_MODE_0_SETTINGS);
//waitForReady
while(input(READY) != 0) ;////not yet
output_high(AD7730_SELECT);
//---------Internal Full Calibartion----------------------------
printf("Internal Full Calibartion...\r\n");
output_low(AD7730_SELECT);
SendAD_Data(CR_SINGLE_WRITE | CR_MODE_REGISTER);
SendAD_Data(MR1_MODE_INTERNAL_FULL_CALIBRATION | CURRENT_MODE_1_SETTINGS);
SendAD_Data(CURRENT_MODE_0_SETTINGS);
//waitForReady
while(input(READY) != 0) ;////not yet
output_high(AD7730_SELECT);
//--------------------------------------------------------------
//---------------SET CONTINOUS MODE-----------------------------
printf("SET CONTINOUS MODE...\r\n");
output_low(AD7730_SELECT);
SendAD_Data(CR_SINGLE_WRITE | CR_MODE_REGISTER);
SendAD_Data(MR1_MODE_CONTINUOUS | CURRENT_MODE_1_SETTINGS);
SendAD_Data(CURRENT_MODE_0_SETTINGS);
//waitForReady
while(input(READY) != 0) ;////not yet
output_high(AD7730_SELECT);
//--------------------------------------------------------------
//---------------START CONTINUOUS READ--------------------------
printf("START CONTINUOUS READ...\r\n");
output_low(AD7730_SELECT);
SendAD_Data(CR_CONTINUOUS_READ_START | CR_DATA_REGISTER);
output_high(AD7730_SELECT);
//--------------------------------------------------------------
}
int8 ReadStatus(void)
{
int8 status;
output_low(AD7730_SELECT);
delay_ms(5);
spi_write(CR_SINGLE_READ| CR_STATUS_REGISTER);
status = spi_read(0);
output_high(AD7730_SELECT);
return status;
}
int16 Read_Mode(void)
{
int16 data;
int8 ModeH;
int8 ModeL;
output_low(AD7730_SELECT);
delay_ms(5);
spi_write(0x12); //send comm reg for read from MODE reg(opcode)
ModeH = spi_read(0); //read high byte
ModeL = spi_read(0); //read low byte
data = (ModeH<<8)|ModeL;
delay_ms(20);
output_high(AD7730_SELECT); //CS = 1
return data;
}
int8 ReadDAC(void)
{
int8 DAC;
output_low(AD7730_SELECT);
delay_ms(5);
spi_write(CR_SINGLE_READ| CR_DAC_REGISTER);
if( spi_data_is_in()){
DAC = spi_read(0);
printf("Incoming Data\r\n");
}
output_high(AD7730_SELECT);
return DAC;
}
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AD7730.h
| Code: |
#define READ_ONLY 0xFF
//Communication Register Values
#define CR_SINGLE_WRITE 0x00
#define CR_SINGLE_READ 0x10
#define CR_CONTINUOUS_READ_START 0x20
#define CR_CONTINUOUS_READ_STOP 0x30
#define CR_COMMUNICATION_REGISTER 0x00 //Write only
#define CR_STATUS_REGISTER 0x00 //Read only
#define CR_DATA_REGISTER 0x01
#define CR_MODE_REGISTER 0x02
#define CR_FILTER_REGISTER 0x03
#define CR_DAC_REGISTER 0x04
#define CR_OFFSET_REGISTER 0x05
#define CR_GAIN_REGISTER 0x06
#define CR_TEST_REGISTER 0x07
//Mode Register Values
#define MR1_MODE_IDLE 0x00
#define MR1_MODE_CONTINUOUS 0x20 //Standard Operation
#define MR1_MODE_SINGLE 0x40
#define MR1_MODE_STANDBY 0x60
#define MR1_MODE_INTERNAL_ZERO_CALIBRATION 0x80
#define MR1_MODE_INTERNAL_FULL_CALIBRATION 0xA0
#define MR1_MODE_SYSTEM_ZERO_CALIBRATION 0xC0
#define MR1_MODE_SYSTEM_FULL_CALIBRATION 0xE0
#define MR1_BU_BIPOLAR 0x00 //+- voltage defined by MR0_RANGE
#define MR1_BU_UNIPOLAR 0x10 //0 to voltage deifined by MRO_RANGE
#define MR1_WL_24_BIT 0x01
#define MR1_WL_16_BIT 0x00
#define MR0_HIREF_5V 0x80
#define MR0_HIREF_2P5V 0x00
#define MR0_RANGE_10MV 0x00
#define MR0_RANGE_20MV 0x01
#define MR0_RANGE_40MV 0x02
#define MR0_RANGE_80MV 0x03
#define MR0_CHANNEL_1 0x00
#define MR0_CHANNEL_2 0x01
#define MR0_CHANNEL_SHORT_1 0x02 //Used for internal noise check
#define MR0_CHANNEL_NEGATIVE_1_2 0x03 //Unknown use
#define MRO_BURNOUT_ON 0x04 //Advanced, to check if loadcell is burnt out
//Filter Register Values
#define FR2_SINC_AVERAGING_2048 0x80 //Base sample rate of 50 Hz
#define FR2_SINC_AVERAGING_1024 0x40 //Base sample rate of 100 Hz
#define FR2_SINC_AVERAGING_512 0x20 //Base sample rate of 200 Hz
#define FR2_SINC_AVERAGING_256 0x10 //Base sample rate of 400 Hz
#define FR1_SKIP_ON 0x02 //the FIR filter on the part is bypassed
#define FR1_SKIP_OFF 0x00
#define FR1_FAST_ON 0x01 //FIR is replaced with moving average on large step, sinc filter averages are used to compensate
#define FR1_FAST_OFF 0x00
#define FR0_CHOP_ON 0x10 //When the chop mode is enabled, the part is effectively chopped at its input and output to remove all offset and offset drift errors on the part.
#define FR0_CHOP_OFF 0x00 //Increases sample rate by x3
//DAC Register Values
#define DACR_OFFSET_SIGN_POSITIVE 0x00
#define DACR_OFFSET_SIGN_NEGATIVE 0x20
#define DACR_OFFSET_40MV 0x10
#define DACR_OFFSET_20MV 0x08
#define DACR_OFFSET_10MV 0x04
#define DACR_OFFSET_5MV 0x02
#define DACR_OFFSET_2P5MV 0x01
#define DACR_OFFSET_NONE 0x00
//current settings
#define CURRENT_MODE_1_SETTINGS (MR1_BU_UNIPOLAR | MR1_WL_24_BIT)
#define CURRENT_MODE_0_SETTINGS (MR0_HIREF_5V | MR0_RANGE_10MV | MR0_CHANNEL_1)
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init.c
| Code: | /*----------------------------------------------------------------------------
File: S_INIT.C
Description
Implementation of InitSystem() function.
Project : Operating System for 16f88---->Test weighing scale with AD7730
Created for Version: 1.0
Updated for Version: 1.0
Last Date Modified : 06/02/2016
Copyright(c) 2016 by Chris_Kal
All Rights Reserved.
----------------------------------------------------------------------------*/
/******************* Pin Description...**************************************/
//1 RA2/AN2/CVREF/VREF- NOT USED OUTPUT
//2 RA3/AN3/VREF+/C1OUT NOT USED OUTPUT
//3 RA4/AN4/T0CKI/C2OUT NOT USED OUTPUT
//4 RA5/MCLR/VPP NOT USED OUTPUT
//5 VSS
//6 RB0/INT/CCP1 AD7730_READY INPUT
//7 RB1/SDI/SDA SPI_SDI INPUT
//8 RB2/SDO/RX/DT SPI_SDO OUTPUT
//9 RB3/PGM/CCP1 AD7730_SELECT OUTPUT
//10 RA1/AN1 SOFT UART TX OUTPUT
//11 RA0/AN0 SOFT UART RX INPUT
//12 RA7/OSC1/CLKI NOT USED OUTPUT
//13 RA6/OSC2/CLKO NOT USED OUTPUT
//14 VDD
//15 RB7/AN6/PGD/ NOT USED OUTPUT
//16 RB6/AN5/PGC/ NOT USED OUTPUT
//17 RB5/SS/TX/CK NOT USED OUTPUT
//18 RB4/SCK/SCL SPI_SCK AUTO
/*The following files must be place to the main file (internal clock 8MHz)
#include <16F88.h>
//#fuses HS,NOWDT,NOPROTECT,NOBROWNOUT,NOLVP,NOPUT,NOWRT,NODEBUG,NOCPD
#fuses INTRC_IO,NOWDT,NOPROTECT,NOBROWNOUT,NOLVP,NOPUT,NOWRT,NODEBUG,NOCPD
#use delay(clock=8000000)
#define AD7730_SELECT PIN_B3
#define SPI_SCK PIN_B4
#define SPI_SDI PIN_B1 //mosi
#define SPI_SDO PIN_B2 //miso
#use spi(master, di=SPI_SDI, do=SPI_SDO, clk=SPI_SCK, mode=0, baud=500000, stream=STREAM_SPI_AD7730,FORCE_HW)//or baud=1000000
//SOFT UART SETUP
#use rs232(baud=9600, xmit=PIN_A1, rcv=PIN_A0,FORCE_SW)
*/
//#include <16F88.h>
/********Init System***********/
void InitSystem(void)
{
set_tris_a(0x02);//RA0 Software Uart Input
set_tris_b(0x23);//pins 5, 0 & 1 are inputs all others are outputs
//setup_psp(PSP_DISABLED);
/*setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF); */
//setup_CCP1(CCP_OFF);
//setup_CCP2(CCP_OFF);
output_high(AD7730_SELECT);//set critical I/O
}
|
main file
| Code: | /*----------------------------------------------------------------------------
File: weighing.c
Description
Main application for Weighing scale using AD7730
Project : Operating System for 16f88---->Test weighing scale with AD7730
Created for Version: 1.0
Updated for Version: 1.0
Last Date Modified : 24/02/2016
Copyright(c) 2016 by Chris_Kal
All Rights Reserved.
----------------------------------------------------------------------------*/
#include <16F88.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#fuses INTRC_IO,NOWDT,NOPROTECT,NOBROWNOUT,NOLVP,NOPUT,NOWRT,NODEBUG,NOCPD
#use delay(clock=8000000)
#use rs232(baud=9600, xmit=PIN_A0, rcv=PIN_A1,FORCE_SW)
#include "AD7730.c"
#include "s_init.c"
#define SPI_SCK PIN_B4
#define SPI_SDI PIN_B1 //mosi
#define SPI_SDO PIN_B2 //miso
#use spi(master, di=SPI_SDI, do=SPI_SDO, clk=SPI_SCK, mode=1, baud=250000, FORCE_HW,MSB_FIRST)//or baud=1000000
//SOFT UART SETUP
int8 result1;
int8 result2;
int8 result3;
int16 mode;
unsigned long result;
int8 first=0;
int8 nDAC;
int8 second;
int8 third;
void main(void)
{
InitSystem();
output_low(RESET);
delay_ms(250);
output_high(RESET);
delay_ms(250);
printf("Welcome\r\n");
//SendAD_Data(CR_SINGLE_WRITE | CR_MODE_REGISTER);
//delay_ms(500);
//spi_write(0xff);
first = ReadStatus();
printf("status is 0x%x\r\n",first);
// delay_ms(500);
nDAC = ReadDAC();
printf("DAC is 0x%x\r\n",nDAC);
mode=Read_Mode();
printf("Mode is 0x%x \r\n",mode);
output_low(AD7730_SELECT);
SendAD_Data(CR_SINGLE_WRITE | CR_MODE_REGISTER);
SendAD_Data(0x80);
SendAD_Data(CURRENT_MODE_0_SETTINGS);
while(input(READY) != 0) ;////not yet
output_high(AD7730_SELECT);
delay_ms(500);
mode=Read_Mode();
printf("Mode is 0x%x \r\n",mode);
//waitForReady
AD7730_Init();
printf("Init finished\r\n");
printf("Reading Registers.......\r\n");
delay_ms(500);
first = ReadStatus();
printf("status is 0x%x\r\n",first);
delay_ms(50);
mode=Read_Mode();
printf("Mode is 0x%x \r\n",mode);
while(TRUE)
{
//From the data sheet, we need to read bytes continously but hold the AD7730 DIN pin (Arduino MOSI) low, so we send 0b0000 0000 three times
output_low(AD7730_SELECT);
SendAD_Data(CR_CONTINUOUS_READ_START | CR_DATA_REGISTER);
output_high(AD7730_SELECT);
while(input(READY) != 0) ;
output_low(AD7730_SELECT);
SendAD_Data(0x30);
output_high(AD7730_SELECT);
delay_ms(250);
output_low(AD7730_SELECT);
SendAD_Data(0x11);
result1 = spi_read(0);
result2 = spi_read(0);
result3 = spi_read(0);
output_high(AD7730_SELECT);
printf("Data Registers (hex)\r\n ");
printf("result1, HEX%x\r\n",result1);
printf("result2, HEX%x\r\n",result2);
printf("result3, HEX%x\r\n",result3);
result = result3 + result2 * 256L + result1 * 256L * 256L;
printf("result %Ld\r\n",result);
delay_ms(2500);
}
}
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On reset according to ad7730 datasheet the reset status reg seems to be fine (I read 0xc0) but after that all other regs is read 0.
I forgot to give you wirings:
AD7730 Board Easy PIC 6 (16f88)
SDI RB1
SDO RB2
CS/ RB3
SCK RB4
RDY/ RB5
RESET/ RB6
SYNC/ VCC
POL JUMPER TO GND
any ideas????
Thanks in advance
Chris |
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asmboy
Joined: 20 Nov 2007
Posts: 2128
Location: albany ny
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| Posted: Sat Feb 27, 2016 6:29 am |
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in the ccs manual , spi_write() / spi_read() includes the following info:
| Code: |
This function is only available on devices with SPI hardware.
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the hardware function in the F88 for SPI is on C3,4,5
your declaration #use spi is for software based SPI on other pins.
it doesn't work the way you think.
the problem:
you are mixing soft spi setup -with the HARDWARE only commands
of spi_read spi_write
They don't mix and match. time to read the CCS manual -
i might add that code like this:
| Code: | | SendAD_Data(MR1_MODE_INTERNAL_ZERO_CALIBRATION | CURRENT_MODE_1_SETTINGS); |
is actually lot LESS CLEAR than
| Code: |
send_AD(0x14); // MR1_MODE_INTERNAL_ZERO_CALIBRATION ,CURRENT_MODE_1_SETTINGS
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because for debug it's too much wasted effort to figure out the bit pattern when its a bunch of defines - that could themselves be faulty.
If ANY of that stuff was VARS - it would be different - but these are #defines and not subject to change, - but IMHO, its less clear if you actually got the code right -- the way you over-document it - just my 2 cents |
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akaka
Joined: 18 Jul 2012
Posts: 14
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| Posted: Sat Feb 27, 2016 7:24 am |
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Hi asmboy,
Thanks for your reply but I think you are a little bit confused.
16f88 is a 18 pin device there is no port C availiable.
Take a look at the following link which is the datasheet of 16f88
http://ww1.microchip.com/downloads/en/DeviceDoc/30487D.pdf
my configuration is proper for hardware SPI pins.
regards
Chris |
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asmboy
Joined: 20 Nov 2007
Posts: 2128
Location: albany ny
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| Posted: Sat Feb 27, 2016 7:48 am |
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yes - i had pins for F886 in my head - sorry
the KEY comment stands about mixing soft SPI with hard --
i still suspect that setup_spi() - not #use spi is what you want
ie: that you are not doing what you think in SPI terms.
big picture: you do setup for SOFT spi
but then use the HARD function - which is not set up the same way.
so yes - you can see data clocked and everything - but bit order may not be right because of your "mix & match" code |
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akaka
Joined: 18 Jul 2012
Posts: 14
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| Posted: Sat Feb 27, 2016 8:13 am |
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| asmboy wrote: | | because of your "mix & match" code |
can you be more detailed about that???
I haven't found any info in ccs manual about #use spi command isused only in software interfacing.
On the contrary FORCE_HW commands is used to configure hardware pins
I'll check in .lst file if the proper registers are configured as it should be and I will keep you informed.
Tomorrow I am going to check it using oscilloscope. |
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asmboy
Joined: 20 Nov 2007
Posts: 2128
Location: albany ny
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| Posted: Sat Feb 27, 2016 8:36 am |
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the manual details it rather well.
when you read the bold topic SPI
you see the following:
For software support, see #USE SPI.
you are incorrectly mixing #USE - which is for soft spi code
with hard code OUTPUT and INPUT
setup_spi() does not require a #USE SPI declaration
what is most telling is this:
go READ the heading for setup_spi()
and see what I/O functions are associated with IT.
then read
#USE SPI
and note that the ONLY function associated with IT is
| Quote: |
Also See: spi_xfer() |
best of luck learning SPI for CCS |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Sat Feb 27, 2016 10:37 am |
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Also, #use spi() defaults to 32-bit transfers. If you're doing only 8-bit
transfers in your code with spi_xfer(), the easiest way to fix this is to
add the BITS=8 parameter as shown in bold below:
| Quote: | | #use spi(master, di=SPI_SDI, do=SPI_SDO, clk=SPI_SCK, mode=1, baud=250000, FORCE_HW,MSB_FIRST, BITS=8) |
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