# Recent content by dope40

1. ### 16f882 TMR1 as frequency counter problem

Hi, I am trying to make a frequency counter using a pic 16f882 . The idea is using TMR1 to measure the pulse period and use it to get the frequency. I am using a 16 MHz crystal so that TMR1 increases every 250ns ( FOSC/4 and 1:1 Prescale Value ) Here is the code : #include <xc.h> //...
2. ### USB Trace impedance conundrum

Hi , I have recently been making a board with a usb connector and FTDI FT232RL. The problem is that i am using a 2 layer board. I used Saturn PCB Calculator , but the traces have to be too big . So , the conundrum is that when i saw the SparkFun USB to Serial Breakout - FT232RL...
3. ### very accurate frequency counter

When i am done counting the pulses of the multiple times how do i convert it into a single frequency.
4. ### very accurate frequency counter

If i use x10 Frequency multiplier ? Then the Frequency for 10 RPM is 3Hz. so the resulution has to be 1 Hz , but it has to go from 150Hz to 15KHz.(So if i messure 313 Hz > when i divide it by 10 i get 31.1 Hz > or in a 4 cylinder engine 940 RPM )
5. ### very accurate frequency counter

The formula to convert the RPM to Hz (on the ignition coil ) is X=((number of cylinders/2)/60)*RPM The engine will be working around 900 RPM but i need to be able to control it with 10 RPM interval. Here is a simple calculator that i made to calculate the RPM in Hz (number of sparks)
6. ### very accurate frequency counter

I am trying to get engine rpm . The frequency depends on the number of cylinders and RPM thats why it needs to be between 15Hz and 1.5KHz . The accurasity needs to be 10 RPM (on a 16 cylinder engine that is 1.3 Hz , but on a 4 cylinder engine that is 0,3 Hz ) . I just recenty started using PIC...
7. ### very accurate frequency counter

Hi , i want to build very accurate frequency counter (0.1Hz accurate ) . The range is from ~15 Hz to ~1.5 KHz.I am using PIC and uC , also i am using flowcode , so if any has any sugestion i would be very happy to hear them. P.S Sorry for the bad grammar but English is not my native language.
8. ### frequency counter flowcode help

Hi , so i recently started using flowcode 5 , and i want to make a frequency counter/meter.I found a great example but i doesnt seem to work for frequensys bigger then 18 Hz .I need it to work from 1 Hz to around 1KHz . but it seems that i cant make it going.So if there is a flowcode expert...
9. ### LCD PIC menu build help

Hi , because i wasn't able to find an answer i was hoping you can help.I am trying to build 16x2 lcd menu to change the values of "char",but i dont know how.I need to make the menu and browse it and also to change what the buttons are doing after i come into a submenu so i can change the value...
10. ### Launch Control Help !!

Is it possible to make work in that range or should i try another circuit?
11. ### Launch Control Help !!

Hi, thanks for the fast reply... i have try this on my car but if i set it to 4000 rpm it drops to 3900 and it kicks again ... but i want to drop down to about 3950 so i get proper boost.I changed VR1 to 100K so i can get rpm range from ~2800 to ~5800.I tried changing VR1 and VR3 various values...
12. ### Launch Control Help !!

Hi , i found this circuit on the net .. (https://code.google.com/p/ecureverse/wiki/LaunchControl) ...... So my question is how does the hysteresis work , and also how can i make it faster because its little slow for my need , i changed the VR1 with 150K pot, VR3 with 50K adjust VR2 so that is...
13. ### potentiometer problem!!

can i use a optocoupler to change the value of an rc circuit?
14. ### formula convertion problem

Here is the file ... i hope its ok
15. ### formula convertion problem

how can i multiplex the value on to 3 CC 7-segment displays?