| ??? 10/26/05 04:39 Read: times |
#102951 - Timer 2 for PWM... Responding to: ???'s previous message |
U Kaz said:
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I am trying to use timer 2 of AT89S8252 to generate PWM, I have read the data sheet but could not get enough information, I was wondering if you guys can help, AT89S8252s timer 2 is same as AT89C52s. This means that it can not support hardware PWM. You can generate software PWM, but you will be unable to generate high frequency PWM by software. U Kaz said:
what is Timer 2 Interrupt vector address? For External interrupt 0 the vector address is 0003H So just go on adding 08 to get the next vector location For Timer 0 interrupt the vector address is 000BH For External interrupt 1 the vector address is 0013H For Tomer 1 interrupt the vector address is 001BH For Serial interrupt the vector address is 0023H For Timer 2 interrupt the vector address is 002BH U Kaz said:
If I want to specify Timer2 as in "auto-reload timer" mode, can I do it simply with this command MOV T2CON,#00H and then I can start/stop timer by controlling TR2. Timer 2 is a 16-bit Timer/Counter that can operate as either a timer or an event counter. The type of operation is selected by bit C/T2 in the SFR T2CON. Timer 2 has three operating modes: capture, auto-reload (up or down counting), and baud rate generator. The modes are selected by bits in T2CON. Timer 2 in timer mode is auto reload only unlike T0 and T1. RCAP2H and RCAP2L are the resistors which hold the auto reload values of timer 2. So if you want to change the count, you have to modify these resistor contents and they will be auto reloaded in timer mode after each roll over. U Kaz said:
how much role TMOD register has to play in initialising Time 2. None. It is for T0 and T1. |
