LPC2114 ; 14.7456 MHz XTAL PCLK configured to 14.7456 MHz After using PCLK to initialize the real time clock along with other peripherals (UART, Timers), I noticed the RTC time registers (MIN, SEC, HOUR, etc.) are going 2 times faster than typical a stopwatch (ie. I wait 10seconds and the RTC says 20). code.... .......... CCR = AMR = CIIR = ILR = 0; //clear all RTC Misc registers SEC = MIN = HOUR = 0; //clear timer registers being used //Setup Prescalar Values PREINT = (PCLK/32768) - 1; //integer value PREFRAC = PCLK - ((PREINT + 1)* 32768); //fraction value CCR |= RTC_RESET; //reset timer CCR &= ~RTC_RESET; CCR |= RTC_ENABLE; //start timer ............... After following the documentation as closely as possible, I'm still not sure why the RTC's going twice as fast. Can anyone clarified this issue?
Message
RTC manipulation (ctd.)
2004-10-05 by Leighton Rowe
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