- Sun Oct 12, 2008 10:02 am
#56944
in order to generate 5ms delay using 11.0592mhz crystal, what are the values to be loaded into TH0 and TL0? (mode1, 16 bit counter)
in mazidi, the values say:
5ms/1.085us=60926 thus TH=EE and TL=00
but another book tells me to do the no. to be loaded is19457
and also instructs to perform the following calculation before lading the values in TH and TL:
TH0 * 256 + TL0 = 19457
assuming TL0=1
TH0=76.
thus the values to be loaded are:th=4c and tl=01
which one is correct?
Also;
when the timer in 8051/89c51 is innitialised, it counts up to ffffh, in the mean time, can the other registers be used for other purposes, or do i need another microcontroller to do the job? my project is regarding RTC, so i need accuracy. i don't want to burden the microcontroller and get errors as a result, but at the same time i don't want to have 2 microcontrollers eating up the power....
i intend to use the CF in the TCON to generate a pulse at any of the port pins, and then use this pulse to drive the other microcontroller.
can i use a single ocsillator to provide the clock to both the microcontrollers or do i need 2 oscillators?
please help!!!
in mazidi, the values say:
5ms/1.085us=60926 thus TH=EE and TL=00
but another book tells me to do the no. to be loaded is19457
and also instructs to perform the following calculation before lading the values in TH and TL:
TH0 * 256 + TL0 = 19457
assuming TL0=1
TH0=76.
thus the values to be loaded are:th=4c and tl=01
which one is correct?
Also;
when the timer in 8051/89c51 is innitialised, it counts up to ffffh, in the mean time, can the other registers be used for other purposes, or do i need another microcontroller to do the job? my project is regarding RTC, so i need accuracy. i don't want to burden the microcontroller and get errors as a result, but at the same time i don't want to have 2 microcontrollers eating up the power....
i intend to use the CF in the TCON to generate a pulse at any of the port pins, and then use this pulse to drive the other microcontroller.
can i use a single ocsillator to provide the clock to both the microcontrollers or do i need 2 oscillators?
please help!!!