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Hello... am still struggling to get the ultrasonic sensor to get distance readings:cry: :cry: :cry: anyway i used the motion sensor example using timer 0 you send to me but the problem is that the output "distance" shown on the LCD is always = 255 mm so what's wrong , also i might have told you this...

hello... from a pin in the pic i send a trigger pulse for at least 10 microseconds to the sensor then the sensor echo pin will keep sending high signal to another pin in the pic until it receives an echo back and immediately lowers its echo that was going to the pic pin,for that i use a timer to sta...

will that is ok , but i thought that if it wasn't working in simulation it wont be working after i upload the hex file to the chip and see the output,so if i upload the program to the chip i will be able to see the variable that will count how many times timer1 have overflowed incrementing on the lc...

no i am only simulating in flowcode3 and watching the counter for the overflow on an lcd screen

hi... i think i might have found my problem...i used pic16f877a and just wrote a simple program with an interrupt icon,the program counts how many times timer1 overflows,just like that .but it seems that timer1 never overflows :!: :!: :!: ,i replaced the interrupt icon timer1overflow with timer0 ove...

why :?: :?: :?: :?: :?: :?: do i need load the flowcode variables into the timer like this FCV_TMR1H = tmr1h; FCV_TMR1L = tmr1l; and then to read the timer variables into flowcode use the following. FCV_TMR1H = tmr1h; FCV_TMR1L = tmr1l; and where exactly to insert each one in my program :?: :?:

wow :shock: :shock: thanks for the very fast reply... i have posted this question before,,,so am sorry if this is not appropriate http://matrixmultimedia.com/mmforums/viewtopic.php?f=5&t=4101 still cant get anything from my SRF05 sensor :cry: :cry: :cry: :cry: i did as mentioned in the linked post s...

what registers are needed to be controlled else than t1con register to control timer1 in pic 16f877,do i need to control register intcon register or PIE ????to get time fro timer 1

hello again... still cant get anything from my SRF05 sensor :cry: :cry: :cry: :cry: i did as mentioned above step by step but still nothing is working :cry: :cry: this is what i did using pic16f877 and 8 mhz crystal 1. Turn Sensor Pwr Hi Delay for 100ms 2.C-code Containing tmr1h=FCV_CAPTUREH; tmr1l=...

lets say i don't know how to use timers at all :roll: :roll: :roll: and i need to find another way to calculate the time for the ultrasonic sensor echo pulse transmit and receive period so what if i create a counter inside a while loop and this counter starts counting from zero to an unspecified val...

What C instruction will cause timer1 to start timing ?
Is it
tmr0h = 1;
tmr0l = 1;
or something else

and what C code will cause the timer to stop or be disabled ?

and what C instruction will turn on the timer1 with a predefined prescaler 1 or 2 or 4 or 8?
is it
t1con = 0x##; ##=some numbers

cant you see my code to see what i am missing in C-codes
i used
tmr1=0;
FCV_TMR1H=tmr1h;load a high start up value into the timer

FCV_TMR1L=tmr1l;load a low start up value into the timer

FCV_TMR1=tmr1;


is these C-codes are right??

still cant understand why,when i change the PIC target from 16f877a to 16f877 a message tells me that flow code is unable to run one or more commands....

Hello...
and what about using interrupt timer1 over flow????does i need it based on my calculations i don't need it

Am starting AT LAST!!! to understand what is going on with the motion sensor2 example so if am using an 8MHz XTAL crystal and a prescaler of 1/8 and system division by four>>>how do we do that???i don't know!!can someone tell me??>> then each instruct cycle time will equal 2 micro seconds then assum...

why i cant create a timer1 overflow interrupt using pic16f877 but i can do that with pic16f877a?????

i receive this message when i compile the motion sensor 2 example Warning unreferenced functions removed: FCD_LCDDisplay0_GetDefines in: C:\Documents and Settings\khaled\Desktop\MotionSensor22.c FCD_LCDDisplay0_Command in: C:\Documents and Settings\khaled\Desktop\MotionSensor22.c FCD_LCDDisplay0_Raw...

So i understand that i can change PIN C2 to any other PIN, i thought that i need PIN C2 because there is a C-Code FCV... and this code works with input capture PINS???so i can easily just change the pin C2....and the example will still work fine...

actually am building a fire fighting robot and i am facing a lot of problems in programming,,,,to see my robot outside design go to
http://letsmakerobots.com/frontpage/panel?page=0%2C7

second photo
look for "HOLY-HELL "A.F.F.R under the name khalchris

thanks again and yes i have seen your example PWM engine for a servo,am new to flow wcode and C-Pic programming but i try to understand more and more every day...actually i have a lot of questions that i want to ask about your example,i will again see it and try to understand how you wrote it,but i ...

thank you for your help ....
but what do you mean by too many jumps?

i connected an LCD screen to PIC16f877 and used the motion sensor2 example to see the distance on it,the lcd works fine but it gives me all black blocks,i checked the LCD pins on pic they were giving signals except for the pin B5 which is the enable pin it was always low and didn't send any output a...

this is a servo position control program done by me....i don't know if it is correct so i hope someone check it for me and tell me if there is a mistake or and change that should be done... the program will simply change the position of the servo when turning CW to turning CCW when reaching some def...

do i have to use pin C2 or i can use any other pin?????

how did you find that each clock tick will need 6.51us??????
can you show me the calculations??