On Sat, 2005-07-09 at 15:29 -0400, Olin Lathrop wrote:
> James Humes wrote:
> > I'm working with a PIC16F913 and
> > trying to implement I2C master mode on two of its pins (SCL, SDA). I
> > have put a 10K resistor on each line to pull it up to Vcc
> 
> That's a pretty high value.  It may cause trouble unless your bit rate is
> really slow, like below 10Kbits/sec maybe.  Check the rise time on the
> scope.

Actually that isn't that high. For example, the MChip datasheet for the
24C02C EEPROM (page 4) says:

"...the SDA requires a pull-up resistor to Vcc (typical 10k for 100kHz,
2k for 400kHz)."

While I more commonly use lower values, 10k is completely reasonable in
my mind for "normal" I2C speeds which are on the slower side, and
definitely doesn't imply running < 10khz. 

TTYL

-----------------------------
Herbert's PIC Stuff:
http://repatch.dyndns.org:8383/pic_stuff/

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