robotpic
29-11-2010, 11:57 AM
e dung pic 18f4331 e . mọi người xem giúp nhé
T PWM:
công thuc tính: pr2= TPWM/(4*Tosc*TMR2prescale)-1
fosc = 20 Mhz=20,000,000, Tosc=1/20,000,000=0.00,000,025 s
Fpwm = 10 KHz=10,000Hz,Tpwm=1/10000=0.0001s
TMRprescaler = 4
==> PTPER =124
Tpwm= (duty)*Tosc*tmr2 prescale
vd: 100% Tpwm=0.0001s ===> duty=500
50% Tpwm=0.00005s ===> duty=250
////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////
T POWER PWM // ho 18f4331 pic nay co 2 che do ===> 2 cach tinh khac nhau
O che do Free run:
PTPER = (fosc*Tpwm)/(4*PTMR prescaler) - 1
fcy = 20 Mhz=20,000,000, Fpwm = 10 KHz=10,000Hz, PTMRprescaler = 4
==> PTPER =124
Tpwm= (duty)*Tosc*tmr2 prescale
vd: 100% Tpwm=0.0001s ===> duty=500
50% Tpwm=0.00005s ===> duty=250
T PWM:
công thuc tính: pr2= TPWM/(4*Tosc*TMR2prescale)-1
fosc = 20 Mhz=20,000,000, Tosc=1/20,000,000=0.00,000,025 s
Fpwm = 10 KHz=10,000Hz,Tpwm=1/10000=0.0001s
TMRprescaler = 4
==> PTPER =124
Tpwm= (duty)*Tosc*tmr2 prescale
vd: 100% Tpwm=0.0001s ===> duty=500
50% Tpwm=0.00005s ===> duty=250
////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////
T POWER PWM // ho 18f4331 pic nay co 2 che do ===> 2 cach tinh khac nhau
O che do Free run:
PTPER = (fosc*Tpwm)/(4*PTMR prescaler) - 1
fcy = 20 Mhz=20,000,000, Fpwm = 10 KHz=10,000Hz, PTMRprescaler = 4
==> PTPER =124
Tpwm= (duty)*Tosc*tmr2 prescale
vd: 100% Tpwm=0.0001s ===> duty=500
50% Tpwm=0.00005s ===> duty=250