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Message |
Fabian
Guest
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| DS1302 troubles |
 Posted: Mon Apr 12, 2004 8:09 am |
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I get strange reading when trying to get my time values from DS1302. i've used the example schem as supplied with the DS1302 datasheet.
from ds1302.c:
| Code: |
#define RTC_SCLK Pin_A2
#define RTC_IO Pin_A3
#define RTC_RST Pin_A4
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the example that's provided with CCS uses more pins than i, ... what gives?
from ex_rtcclk.c
| Code: |
#define RTC_SCLK PIN_B1
#define RTC_RST PIN_B2
#define RTC_CE PIN_D0
#define RTC_IO PIN_D1
#define RTC_CLK PIN_D2
#define RTC_DATA PIN_D3
#include <ds1302.c>
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my approach:
i get the need values for time from rs232 input and write them with the supplied function from the ds1302 driver. (tried with BCD formating too)
when i read the clock it returns unreasanable values...
| Code: |
BYTE day=5,mth=6,year=7,dow=1,hour=8,min=1,sec=23;
//macro from bcd 2 dec
#define fromBCD(x) ((x & 0xf)+conv[(x>>4)])
//from dec 2 bcd
byte get_bcd() {
char first,second;
do {
first=getc();
} while ((first<'0') || (first>'9'));
putc(first);
first-='0';
do {
second=getc();
} while ((second<'0') || (second>'9'));
putc(second);
return((first<<4)|(second-'0'));
}
// set clock
void set_clock(){
byte day,mth,year,dow,hour,min;
puts("Year 20: ");
year=get_bcd();
puts("Month: ");
mth=get_bcd();
puts("Day: ");
day=get_bcd();
puts("Weekday 1-7: ");
dow=get_bcd();
puts("Hour: ");
hour=get_bcd();
puts("Min: ");
min=get_bcd();
printf("\n\r %2d,%2d,%2d, %2d um %2d:%2d\n",fromBCD(day),fromBCD(mth),fromBCD(year),fromBCD(dow),fromBCD(hour),fromBCD(min));
rtc_set_datetime(day,mth,year,dow,hour,min);
printf("\n\r %2d,%2d,%2d, %2d um %2d:%2d\n",fromBCD(day),fromBCD(mth),fromBCD(year),fromBCD(dow),fromBCD(hour),fromBCD(min));
printf("\n\r Uhr gestellt");
}
void get_clock()
{
printf("\n\r...%2d:%2d:%2d...\n",fromBCD(hour),fromBCD(min),fromBCD(sec));
}
void main()
{
setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
rtc_init();
/////////////////////////
/////////////////////////
printf("\n\r...start...\n");
set_clock();
do {
get_clock();
delay_ms(3000);
get_clock();
} while (TRUE);
}
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Mon Apr 12, 2004 10:15 am |
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Pin A4 will require a pull-up resistor on it. Do you have one ?
| Quote: | | #define RTC_RST Pin_A4 |
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Guest
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| Posted: Mon Apr 12, 2004 10:54 am |
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| PCM programmer wrote: | Pin A4 will require a pull-up resistor on it. Do you have one ?
| Quote: | | #define RTC_RST Pin_A4 |
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nope, which value should the pull up resistor have? |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Mon Apr 12, 2004 12:00 pm |
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I don't know what your PIC crystal frequency is --
it determines how quickly the clock line will toggle.
At higher ds1302 clock speeds, you need a faster
rise time on the clock edges. Just to be safe,
I would suggest using a 1K pull-up on pin A4. |
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Guest
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| Posted: Mon Apr 12, 2004 12:04 pm |
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I'm using maxim's ds1302 but ist does not work correctly.
My problem is that I am able to set the time when it is running it only echos nonsense
code:
| Code: |
#include <16F877.h>
#fuses HS,NOWDT,NOPROTECT,NOLVP
#use delay(clock=20000000)
#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7)
#include <DS1302.C>
#define RTC_SCLK Pin_A2
#define RTC_IO Pin_A3
#define RTC_RST Pin_A4
BYTE day=1,mth=2,year=3,dow=4,hour=5,min=6,sec=7;
//bcd def
const unsigned int conv[16] = {
0,10,20,30,40,50,60,70,80,90,90,90,90,90,90,90 };
#define fromBCD(x) ((x & 0xf)+conv[(x>>4)])
unsigned int toBCD(unsigned int val)
{
int ctr;
for (ctr=0;ctr<10;ctr++)
{
if (val == conv[ctr])
return(ctr<<4);
else if (val < conv[ctr]) break;
}
--ctr;
return((val-conv[ctr])+(ctr<<4));
} // end bcd def
byte get_bcd() {
char first,second;
do {
first=getc();
} while ((first<'0') || (first>'9'));
putc(first);
first-='0';
do {
second=getc();
} while ((second<'0') || (second>'9'));
putc(second);
return((first<<4)|(second-'0'));
}
void set_clock()
{
puts("Year 20: ");
year=get_bcd();
puts("Month: ");
mth=get_bcd();
puts("Day: ");
day=get_bcd();
puts("Weekday 1-7: ");
dow=get_bcd();
puts("Hour: ");
hour=get_bcd();
puts("Min: ");
min=get_bcd();
puts("sec");
sec=get_bcd();
printf("\n\r %2d,%2d,%2d, %2d um %2d:%2d\n",fromBCD(day),fromBCD(mth),fromBCD(year),fromBCD(dow),fromBCD(hour),fromBCD(min));
rtc_set_datetime(day,mth,year,dow,hour,min);
printf("\n\r clock setup");
}
void get_clock()
{
rtc_get_time(hour,min,sec);
printf("\n\r...%2d:%2d:%2d...\n",fromBCD(hour),fromBCD (min),fromBCD(sec));
}
void main()
{
setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
rtc_init();
printf("\n\r...start...\n");
set_clock();
do {
get_clock();
delay_ms(1000);
get_clock();
} while (TRUE);
} //end main
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Hyperterminal:
| Code: |
start
Year 20:
04
Month:
04
Day:
13
Weekday 1-7:
03
Hour:
12
Min:
00
sec
0 0
13, 4, 4, 3 um 12: 0
... 0: 0: 0...
... 0: 0: 0...
.
.
.
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ferdinand
Guest
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| Posted: Mon Apr 12, 2004 12:05 pm |
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I'm using maxim's ds1302 but ist does not work correctly.
My problem is that I am able to set the time when it is running it only echos nonsense
code:
| Code: |
#include <16F877.h>
#fuses HS,NOWDT,NOPROTECT,NOLVP
#use delay(clock=20000000)
#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7)
#include <DS1302.C>
#define RTC_SCLK Pin_A2
#define RTC_IO Pin_A3
#define RTC_RST Pin_A4
BYTE day=1,mth=2,year=3,dow=4,hour=5,min=6,sec=7;
//bcd def
const unsigned int conv[16] = {
0,10,20,30,40,50,60,70,80,90,90,90,90,90,90,90 };
#define fromBCD(x) ((x & 0xf)+conv[(x>>4)])
unsigned int toBCD(unsigned int val)
{
int ctr;
for (ctr=0;ctr<10;ctr++)
{
if (val == conv[ctr])
return(ctr<<4);
else if (val < conv[ctr]) break;
}
--ctr;
return((val-conv[ctr])+(ctr<<4));
} // end bcd def
byte get_bcd() {
char first,second;
do {
first=getc();
} while ((first<'0') || (first>'9'));
putc(first);
first-='0';
do {
second=getc();
} while ((second<'0') || (second>'9'));
putc(second);
return((first<<4)|(second-'0'));
}
void set_clock()
{
puts("Year 20: ");
year=get_bcd();
puts("Month: ");
mth=get_bcd();
puts("Day: ");
day=get_bcd();
puts("Weekday 1-7: ");
dow=get_bcd();
puts("Hour: ");
hour=get_bcd();
puts("Min: ");
min=get_bcd();
puts("sec");
sec=get_bcd();
printf("\n\r %2d,%2d,%2d, %2d um %2d:%2d\n",fromBCD(day),fromBCD(mth),fromBCD(year),fromBCD(dow),fromBCD(hour),fromBCD(min));
rtc_set_datetime(day,mth,year,dow,hour,min);
printf("\n\r clock setup");
}
void get_clock()
{
rtc_get_time(hour,min,sec);
printf("\n\r...%2d:%2d:%2d...\n",fromBCD(hour),fromBCD (min),fromBCD(sec));
}
void main()
{
setup_adc_ports(NO_ANALOGS);
setup_adc(ADC_OFF);
setup_timer_1(T1_DISABLED);
setup_timer_2(T2_DISABLED,0,1);
rtc_init();
printf("\n\r...start...\n");
set_clock();
do {
get_clock();
delay_ms(1000);
get_clock();
} while (TRUE);
} //end main
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Hyperterminal:
| Code: |
start
Year 20:
04
Month:
04
Day:
13
Weekday 1-7:
03
Hour:
12
Min:
00
sec
0 0
13, 4, 4, 3 um 12: 0
... 0: 0: 0...
... 0: 0: 0...
.
.
.
|
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Fabian
Guest
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| Posted: Mon Apr 12, 2004 1:17 pm |
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| PCM programmer wrote: | I don't know what your PIC crystal frequency is --
it determines how quickly the clock line will toggle.
At higher ds1302 clock speeds, you need a faster
rise time on the clock edges. Just to be safe,
I would suggest using a 1K pull-up on pin A4. |
20Mhz crystal frequ. |
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PCM programmer
Joined: 06 Sep 2003
Posts: 21708
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| Posted: Mon Apr 12, 2004 1:21 pm |
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Does Fabian = Ferdinand ?
Did the pull-up resistor fix your problem,
or do you still have a problem ? |
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Fabian
Guest
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| Posted: Tue Apr 13, 2004 8:51 am |
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jes we're working togehter on thist proŽject.
The problem is still existing.
We are going to have a look at the hardware with an oscilloscope towmorrow.
I'll post again if I can't solve it or do you have any further suggestions.
Thanks Fabian |
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rwyoung
Joined: 12 Nov 2003
Posts: 563
Location: Lawrence, KS USA
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| Posted: Tue Apr 13, 2004 7:53 pm |
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I have code that works with a DS1307 which is not exactly the same part as the DS1302. I can cut and paste my routines if you think that might help you. The code is working on a PIC16F76 and there is also an i2c EEPROM on the bus in addition to the DS1307.
_________________
Rob Young
The Screw-Up Fairy may just visit you but he has crashed on my couch for the last month! |
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Fabian
Guest
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| Posted: Tue Apr 13, 2004 10:03 pm |
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| rwyoung wrote: | | I have code that works with a DS1307 which is not exactly the same part as the DS1302. I can cut and paste my routines if you think that might help you. The code is working on a PIC16F76 and there is also an i2c EEPROM on the bus in addition to the DS1307. |
yes i think that might help me alot.
pleas post it or give me a link to download this file
thanks
fabian |
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