At 05:53 PM 11/26/02 +0000, you wrote:
>(oops...sorry forgot tag)
>
>Using w98; MPLAB 5.40.00
>I need an accurate time period on a 12C509 and testing code on a JW device.
>Made a note of the internal calibration value before erasing.
>Using TMR0 and internal oscillator for timing - set the up the calibration
>constant in the Calibration window in MPLAB.
>
>Here is my problem....when I test on MPLAB simulator the timing period if
>fine and correct for a time period of 1 second I get 999.94 mS. But when I
>programme the JW device the actual timing period is out by 10%. Is this what
>I should expect? Should I use delay timer rather than TMR0?

Silly question, perhaps, but if you're getting a longer time than you
expect.. have you actually set the OSCCAL SFR (0x05) at the
beginning of your program?

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body