ds1307 from f877 to f452 not work

[microkam]

this code is run ok on 16f877,when i download this code on 18f452 there is one problem that the ds1307 not work, in the same time the 24lc256 on the same bus is working good...whats the problem!!!!


define osc 4
DEFINE LOADER_USED 1

DEFINE LCD_DREG PORTB
DEFINE LCD_DBIT 4
DEFINE LCD_RSREG PORTB
DEFINE LCD_RSBIT 3
DEFINE LCD_EREG PORTB
DEFINE LCD_EBIT 2
DEFINE LCD_BITS 4
DEFINE LCD_COMMANDUS 2000
DEFINE LCD_DATAUS 50
DEFINE LCD_LINES 2


DPIN var PORTC.4 'I2C DATA PIN 24LC256 and ds1307,with 4K7 pull up
CPIN var PORTC.5 'I2C CLOCK PIN with pulled up resister 4K7


add var word
d1 var byte
d2 var byte
B0 var byte
sec var byte
sec0 var byte
sec1 var byte
rtcco var byte
rtcad var byte

pause 500
rtcco=$D0
rtcad=0
B0=0
I2CWRITE DPIN,CPIN,rtcco,rtcad,[B0,B0,B0,B0,B0] ' intilization of ds1307
lcdout $FE,1," start"
main:
pause 1000
add=0
d1=9
I2cWRITE DPIN,CPIN,$A0,add,[d1] 'eeprom write
pause 30
I2CREAD DPIN,CPIN,$A1,add,[d2] 'eeprom read
gosub readtime
lcdout $FE,1,#d2," ",#sec
goto main

readtime:
rtcco=$D0
rtcad=0
I2CREAD DPIN,CPIN,rtcco,rtcad,[B0] 'ds1307 read
sec0=B0&%00001111
sec1=B0&%01110000 : sec1=sec1>>4
sec=sec0+sec1*10
return

[Dave]

microkam, I notice you make no mention of a 4.7 k pullup on the data line?

Dave Purola,
N8NTA

[microkam]

the data line and clock line is pulled up with 4K7 ohm ,and this code is runing very good on 16f877 ,but idont know whats the problem on 18f452

[Ingvar]

Perhaps .....

DEFINE I2C_SLOW 1

..... will solve the problem?

[microkam]

i did this..
i defined this
DEFINE I2C_SLOW 1
buts no result

[NavMicroSystems]

microkam,

I can't see anything wrong with your code.

And since you are saying the EEPROM works fine
I would assume the DS1307 is faulty
(or has a bad connection)

[microkam]

there is no faulty in ds1307 because before moment i replace the 18f452 with 16f877 on the same program and it run ok ......
i dont know whats i doing

[Melanie]

Can you try it with a variable instead of a constant in the I2C Address... eg...

RTC var Byte

RTC=$D0
I2CWRITE DPIN,CPIN,RTC,0,[0,0,0,0,0] ' intilization of ds1307

and likewise in reading...

I2CREAD DPIN,CPIN,RTC,0,[B0] 'ds1307 read

there is no need to change between $D0 and $D1 when reading or writing, because PBP manipulates bit zero for you automatically. You only need to concern yourself with the upper seven bits of the address.

Nobody reads FAQ's... makes me wonder why I spent the time doing them in the first place...http://www.picbasic.co.uk/forum/showthread.php?t=587

[microkam]

i edited my programe on the new defined and the ds1307 still not working
,i download the new programe on the 16f877 and all thing is ok
whats the problem!!!
mel, can you see the new programe and tell me whats the wrong

[NavMicroSystems]

Melanie,

you are absolutely right in:

there is no need to change between $D0 and $D1 when reading or writing, because PBP manipulates bit zero for you automatically. You only need to concern yourself with the upper seven bits of the address.

However,
all variants listed should work:
(I would always prefer the first one)

RTC CON $D0
I2CWRITE DPIN,CPIN,RTC,0,[0,0,0,0,0]

RTC var Byte
RTC=$D0
I2CWRITE DPIN,CPIN,RTC,0,[0,0,0,0,0]

I2CWRITE DPIN,CPIN,$D0,0,[0,0,0,0,0]

and even this one
(Bit0 set with I2CWRITE)
works since PBP takes care of Bit0:

I2CWRITE DPIN,CPIN,$D1,0,[0,0,0,0,0]