Test bench set up working well.

Today I have built the Ion current bias generator and tested it on our test bench. The results show that the circuit charged up around 80v from the coil back EMF. The old ignitor has been replaced by a Toyota ignitor and a frequency generator has been used for the trigger signal.

Dual channel zero crossing circuit made

Today I have built a two channel zero crossing detection circuit for use with the PIC32. This circuit converts two variable reluctance position sensor signals into square wave digital signals that the PIC32 can read directly. This design features two LM1815 chips and is simply built on veroboard. I have tested it on our test bench with good results on the scope.

Ion current sampling software started

This week I have begun writing the software which will use the ADC module to sample the ion current traversing the spark gap. This mode of the software sets up the ADC module for manual sampling then the angular event control calls the ion current event every increment of sampling required. This begins the next sample conversion after which the ADC interrupt saves the result into the sample array.

Software sync on engine

Today during testing on the 1ZZ-FE the software was able to synchronise with the crankshaft and attain CRANK SYNC. This is a good milestone that shows the software can work in real applications. Next step is to make a two channel zero crossing detection circuit that can covert the crank and cam VR signals into digital for the PIC32. Thanks to Dennis for lending me his zero crossing circuit.

Software modified to suit 1zz-fe

While the go kart engine is being modified. I have been setting up the software to suit one of the 1zz-fe engines downstairs. These have two inductive pick ups; one 36 minus 2 teeth on the crankshaft and a 4 minus 1 tooth on the camshaft. From my research I have found that the first tooth after the crank missing teeth gap is 36 degrees before cylinder 3 and 2 TDC. The camshaft first tooth after the teeth gap is around 36 degrees before cylinder 4 TDC when the VVTI is in neutral position.

Angular event control mostly functional

The angular event control code is capable of calling the function at what appears to be the correct angle. I have used function pointers to allow different functions to be called from the same output compare interrupt. This allows the user to set up events to occur at a certain angle and choose which function is called and leave the rest to the software.

Event Control Started

This week I have been programming the module which is responsible for angular event control.
So far the soft ware can pick the next event from a list and then calculate which crank sensor tooth it should be time referenced from and the time-stamp with which to trigger the output compare module to start the event.

I am also converting the software to use 16bit integers for angle variables instead of floating point to save on processing time.