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hbl2
- 9th February 2005, 14:16
I've a problem when i interfacing DS1803 to PIC16F819 @ 4Mhz
There are 2 pull-up on SDA and SCL line of 4,7K.

I2CWrite SDA,SCL,%01010000,%10101001,V0

V0 is the value of pot (0-255)

But the resistance of digital pot don't change.
Can you help me?

mister_e
- 9th February 2005, 16:46
can be a few things, where your DS1803 is connected, have you try some lower pull-ups... let's say 1.5-2K ?

Is a simple blink program work on those pin you choose...
the whole code may help. I'll have a look to the datasheet of the DS1803 in a few...

hbl2
- 9th February 2005, 17:01
I tried with 1,5 and 2k res but the res of digital pot don't change

mister_e
- 9th February 2005, 17:08
have a look to the PICLISt

Click Here (http://list.picbasic.com/forum/messages/20/1057.html?978053847)

Dave
- 9th February 2005, 17:09
HBL2, Another thought, but you probably already know this make sure the address bits for the 1803 are in the proper states which acording to your software is a0,a1,a2 all low.

Dave Purola,N8NTA