speak for yourself hahah, i find it absolutely fascinating trying to try to understand the LH/EZK assembly. It allows one to do funky things like light the CEL when knock is detected or timing being pulled. Very useful for tuning!esmth - I thought about using a serial port monitor directly, but I want to be able to do full speed logging (2x per rev). I also hate reverse engineering 8051 assembly code.
I can dump data out the 'serial' port fast enough to stall the engine! I use serial in quotes as i'm actually only using the usart hardware as a shift register and not a normal PC-compatible uart. I can get a byte in or out in 9 machine cycles. The old pc-compatible way that has been used in the past is limited to 3200/6400 baud while my method is about equivalent to 1 megabaud. It needs significant hardware modification though -- a real deal breaker for us trying to make a datalogger or the average tuner!
There are constants in the ezk bin to disable this check! Though, you may be able to fool it buy just adding some voltage to pin an5 of the mcu at the right time if you really want to get super accurate behavioral data. The knock circuit on ezk is a real bear. It has 4 (or 5?) bias settings that configure the sensitivity. It has a very small window after the ignition event that it samples.I may try adding a resistor from the RPM signal to the Knock signal to see if that will fool it.
If you tap a wire from p5.4 of the mcu, (or the base of T100 transistor on EZK) when the line is LOW, ezk is sampling the knock circuit, and here is when you should inject the voltage to the knock adc/circuit. (i think, logic may be reversed.)
In practice, I usually see knock signal ADC values from 0x0 to 0x40-ish while the car is running and driving. assuming the analog reference of the MCU is 5v, that should be a range from 0 to 1.3 volts it expects. Idle it averages like 0x05-0x10 so 0.1-0.2v give or take.
For the full monitor, I'm thinking of starting with an Arduino Pro Micro (32U4 and 3.3v) with an ebay HC05 bluetooth module. This will provide serial port emulation on the PC or Smart Phone. Does anyone else have a preference?
I may be biased, but my day job is programming BLE devices with the nrf 52833/52840 chips. They are very capable and cheap, but they do not have the ease-of-use of the arduino software stack. There might be an unofficial layer though.