i've found this schematic circuit... but the problem is..idunno how to read it... can some one help me... what the partlist, and how to construct this device...
The 16F84 is a standard old PIC, you need a PIC programmer to program it - try reading the 'sticky' in the micro-controller forum.
Presumably you have the code to program in the chip?.
What does the RS232 interface allow you to do?, the 16F84 has 64 bytes of non-volatile memory, perhaps it's for storing parameters there to alter preformance?.
yes, i have the .hex file.. also the .asm of the CDI.. but need to build th PIC programmer hardware first... i've found the simplest Pic programmer in the net.. (if you have some other way please let me know)
is it hard to do this device?? i really2 zero about electronic...
You should start with a simpler circuit first if you cannot read a schematic. For starters, checkout these links to help you learn how to read schematics: **broken link removed** **broken link removed**
Nigel's supposition is correct. The microcontroller is there to adjust the spark advance according to engine speed. It allows for easy starting and then changes according to speed for more power. The hobbyists use a table look-up for the advance settings. See: https://www.rcuniverse.com/forum/m_4344316/tm.htm
In answer to "how does it work," the 400V capacitor connected to the spark coil is charged with rectified current from the alternator, then rapidly discharged through the BT151 SCR , which causes the ignition coil to generate the high voltage (inductive
kick) needed to fire the spark plug. The microcontoller provides the pulse needed to fire the SCR. The pick-up is frequently a Hall sensor, which provides timing information to the microcontroller.