| View previous topic :: View next topic |
| Author |
Message |
jojos
Joined: 30 Apr 2007
Posts: 64
|
| DS2432 connection problem |
 Posted: Mon Jul 13, 2009 3:47 am |
 |
|
Hi. I am using DS2432 with a PIC 18F2520. The read_rom command returns ERR_NODEVICE. I am using the code from CCS. I have connected the DS2432's PIN_1 to the ground and PIN_2 to PIC's PIN_A4 with a pull-up resistor to 5 Volts.
Below is my test code
| Code: |
#include "C:\SotirasLcd\18F2520.h"
#include <string.h>
#include <C:\SotirasLcd\stdlib.h>
//INTRC_IO
#fuses INTRC_IO ,PROTECT,NOLVP,PUT,NOPBADEN,NOBROWNOUT,MCLR//BROWNOUT_SW,BORV27//,BORV27 //INTERNAL OSCILLATOR NO CLOCK
#use delay(clock=4000000)//3276800)
#use fast_io(A)
#use fast_io(B)
#use fast_io(C)
#include "ds2432.c"
void init(void);
#define ON 1
#define OFF 0
#define TOUCH_PIN PIN_A4
#define Led_Collision PIN_C0
#define Led_Ok PIN_C1
#define Led_Nodevice PIN_C2
//#bit Stick_bit =0xF80.0
void main(void)
{
unsigned char reg_matrix[20];
unsigned char flag=15;
unsigned int16 mn;
delay_ms(1000);
init();
init_ds2432();
delay_ms(2000);
while(1)
{
flag=read_rom(*reg_matrix);
if(flag==ERR_COLLISION)
{
output_high(Led_Collision);
output_low(Led_Ok);
output_low(Led_Nodevice);
}
else
if(flag==ERR_OK)
{
output_low(Led_Collision);
output_high(Led_Ok);
output_low(Led_Nodevice);
}
else
if(flag==ERR_NODEVICE)
{
output_low(Led_Collision);
output_low(Led_Ok);
output_high(Led_Nodevice);
}
delay_ms(10);
//flag=15;
}
}
void init(void)
{
set_tris_a(0);
set_tris_b(0);
set_tris_c(0);
PORTA=0;
PORTB=0;
PORTC=0;
setup_adc(NO_ANALOGS);
SETUP_CCP1(CCP_OFF);
SETUP_CCP2(CCP_OFF);
disable_interrupts(global);
return;
}
|
Can you see any error in my code?Thank you |
|
 |
Ttelmah
Guest
|
|
| Posted: Mon Jul 13, 2009 7:05 am |
|
|
First thing, _simplify_.
Testing this chip, could be done with about a ten line program. Just load the libraries, and call the initial test. The more other code you have present, the greater the risk of unexpected effects. The first thing you do when trying to debug a program, should be to throw away code, till you have narrowed it right down.
As a general 'comment', put the #use delay, and fuse lines _above_ any library includes. Though it shouldn't cause a probelm with your code, if you load a library, that uses delays, unless the use delay is already present, you may get problems.
I'm not sure you can Use A4, for such a device. These, depend on detecting the rate of change of the voltage on an input, when the line is released. This will not be the same for A4, as for a normal logic I/O line....
Best Wishes |
|
|
jojos
Joined: 30 Apr 2007
Posts: 64
|
|
| Posted: Mon Jul 13, 2009 12:58 pm |
|
|
| I've already tried another pin and the problem remains. I will put fuses up as you mentioned and see if it was a conflict. Thanks |
|
|
PCM programmer
Joined: 06 Sep 2003
Posts: 21708
|
|
| Posted: Mon Jul 13, 2009 2:55 pm |
|
|
From the ds2432.c file:
| Quote: | // int8 read_rom(int* chip)
//
// *Parameters:
// - chip - pointer to an array in which the chip registration data |
| Quote: |
unsigned char reg_matrix[20];
flag = read_rom(*reg_matrix);
|
This is not correct. You're not passing a pointer to reg_matrix[] correctly.
How should you pass a pointer to an array ?
There is a difference between how a pointer is declared, and how it's passed. |
|
|
jojos
Joined: 30 Apr 2007
Posts: 64
|
|
| Posted: Tue Jul 14, 2009 1:40 am |
|
|
I use the touch_present function for a simple debug. Here is the code:
| Code: |
#include "C:\SotirasLcd\18F2520.h"
//INTRC_IO
#fuses INTRC_IO ,PROTECT,NOLVP,PUT,NOPBADEN,NOBROWNOUT,MCLR//BROWNOUT_SW,BORV27//,BORV27 //INTERNAL OSCILLATOR NO CLOCK
#use delay(clock=8000000)//3276800)
#use fast_io(A)
#use fast_io(B)
#use fast_io(C)
#include <string.h>
#include <C:\SotirasLcd\stdlib.h>
#include "ds2432.c"
void init(void);
#define ON 1
#define OFF 0
#define TOUCH_PIN PIN_A5
#define Led_Collision PIN_C0
#define Led_Ok PIN_C1
#define Led_Nodevice PIN_C2
//#bit Stick_bit =0xF80.0
void main(void)
{
unsigned char reg_matrix[20];
unsigned char flag=0;
unsigned int16 mn;
delay_ms(500);
init();
init_ds2432();
delay_ms(500);
while(1)
{
flag=touch_present();
if(flag==TRUE)
output_high(Led_Ok);
else
output_low(Led_Ok);
delay_ms(50);
}
}
void init(void)
{
set_tris_a(0);
set_tris_b(0);
set_tris_c(0);
PORTA=0;
PORTB=0;
PORTC=0;
setup_adc(NO_ANALOGS);
SETUP_CCP1(CCP_OFF);
SETUP_CCP2(CCP_OFF);
disable_interrupts(global);
return;
}
|
Again the led is off ,that means the DS2432 appears not to be present. |
|
|
PCM programmer
Joined: 06 Sep 2003
Posts: 21708
|
|
| Posted: Tue Jul 14, 2009 11:00 am |
|
|
Read these instructions at the top of the ds2432.c file:
| Quote: |
// init_ds2432()
//
// Should call this function before any others.
// Will reset most 1-Wire devices on the network at once.
// *No returns.
|
|
|
|
jojos
Joined: 30 Apr 2007
Posts: 64
|
|
| Posted: Tue Jul 14, 2009 11:49 pm |
|
|
Ok I have put the init_ds2432 as the first instruction in main. When the while loop executes for the first time the touch_present function gives a TRUE result but when it executes again it gives FALSE result all the time. Any ideas? I can't understand what seems to be the problem.
Edit:
I have changed the output_float(TOUCH_PIN) with
output_high (TOUCH_PIN) in the touch_present function and now it works.
I dont know if i will have to chabge something else in the other functions but the touch_present function now works.Any ideas why i had to make this change?Thank you.
Last edited by jojos on Wed Jul 15, 2009 12:17 am; edited 1 time in total |
|
|
PCM programmer
Joined: 06 Sep 2003
Posts: 21708
|
|
| Posted: Wed Jul 15, 2009 12:16 am |
|
|
It looks like you had it in there before, but I missed it. Did moving it
to the start of main() cause a change in symptoms ?
1. What is the size of the pull-up resistor on the Touch pin ?
| Quote: | #use fast_io(A)
#use fast_io(B)
#use fast_io(C)
set_tris_a(0);
set_tris_b(0);
set_tris_c(0);
PORTA=0;
PORTB=0;
PORTC=0; |
2. Get rid of the fast i/o, TRIS, and direct register i/o statements and
let the compiler set the TRIS. Comment out all 9 statements above.
Then compile and test it. |
|
|
jojos
Joined: 30 Apr 2007
Posts: 64
|
|
| Posted: Wed Jul 15, 2009 12:28 am |
|
|
PCM Programmer the problem was the #use fast_io directives. I let the set_tris directives and the PORTx=0; instructions and it works. I also changed back the output_float(TOUCH_PIN) instruction in the touch_present function.
I don't know how the #use fast_io directives made conflict with the program but now it works. If someone can explain this it's good to know. Thank you anyway for your help. |
|
|
FvM
Joined: 27 Aug 2008
Posts: 2337
Location: Germany
|
|
| Posted: Wed Jul 15, 2009 12:38 am |
|
|
| Quote: | | I don't know how the #use fast_io directives made conflict with the program I don't know how the #use fast_io directives made conflict with the program |
That's rather obvious. Unless explicitly told different, CCS provided drivers are relying on default compiler settings, in this case #use standard_io. The one-wire interface involves a bidirectional pin, with standard_io in effect, the IO direction is automatically set with input() and output_xxx() statements, this operation is required by the driver.
Generally, it isn't a good idea to add arbitrary compiler settings without fully understanding their purpose. |
|
|
jojos
Joined: 30 Apr 2007
Posts: 64
|
|
| Posted: Wed Jul 15, 2009 12:57 am |
|
|
| Thank you FvM for solving my confusion about this matter. It's always good to learn new things. |
|
|
jojos
Joined: 30 Apr 2007
Posts: 64
|
|
| Posted: Mon Jul 20, 2009 4:42 am |
|
|
| I don't want to open a new thread so I am writing my question here. First of all I can't get any access to the full datasheet of DS2432, I believe that in there I can solve many of my wonderings. Maxim Dallas seems to ignore my emails about getting it. Second, DS2432 has 1Kb memory. In the CCS code library it says in the 'write_byte' command that I can set an address of 0-127 range. So how I can access the rest of the memory. I figure in some way the memory is splitted in pages or something like that. So how can I set these pages (if I am correct)? Same thing in the 'read_byte' command. Range for the address is 0-127,136-151. Thank you. |
|
|
FvM
Joined: 27 Aug 2008
Posts: 2337
Location: Germany
|
|
| Posted: Mon Jul 20, 2009 6:26 am |
|
|
| Address range 0 to 127 is representing the 4 R/W memory pages. 128*8 equals 1 kbit, I think. Addresses starting from 128 are special function registers. |
|
|
jojos
Joined: 30 Apr 2007
Posts: 64
|
|
| Posted: Mon Jul 20, 2009 6:45 am |
|
|
| Ok then. But how can I load the page I like before I set the address? |
|
|
FvM
Joined: 27 Aug 2008
Posts: 2337
Location: Germany
|
|
| Posted: Mon Jul 20, 2009 7:54 am |
|
|
I never used DS2432 with PIC or CCS driver, only with Maxim libraries. Thus I can't tell any details related to the DS2432 driver.
You should clarify, what you want to achieve with DS2432 and what's not working as expected. |
|
|
|
FAQ 
Search
Register
Profile 
Log in to check your private messages 
Log in
