Overview -------- The V0.1 board was the first hardware implementation and is not intended for general in car use. It does however drastically simplify testing on stationary engines. Layout ------ The board is a 2 sided 'shield' that is approximately the same width as an Arduino Mega, but extends out at both ends. It has I/O for all the main sensors as well as 4 channels each of ignition and fuel. Populating the board -------------------- The following components are needed to fully populate the board: - R1, R2, R3, R5, R7, R7 = 10k Ohm resistors - R4, R6, R8, R9 = 1k Ohm resistors - D1-D4 = Schottky diode (Eg 1N5819) - C1-C4 = 100nF capacitors rated for at least 6V - Q1-Q4 = TO220 nChannel MOSFETs (Eg STP62NS04Z). Other appropriate MOSFETs will work and maybe substituted but these should have clamping >30V and some protection built in. - U1 = Opto-isolator (Eg CNY17-3). May or may not be needed depending on the type of crank sensor you are using. If your sensor outputs 0-5V directly, this can be left out and the sensor connected directly to digital pin 2 on the arduino Dev Notes --------- The V0.1 board has several drawbacks and issues that are to be addressed for the next version. These include: - Lack of ground screw terminals. The board only has a single ground screw connector which must be shared by all sensors. This is less than ideal both physically and electrically. - The use of an opto-isolator for the crank sensor is of debatable value. Most suitable hall sensors will output 0-5V signals and I'm not sure it's worth the extra cost/space to support 0-12V+ sensors as well. This leads to the next issue: - No support for VR crank sensors. The next version of the board will either use a built in VR conditioner or will allow something such as \[the jbperf VR conditioner board\](http://jbperf.com/dual_VR/v2_1.html) to be plugged in if required - No bias resistors onboard for the 2 temperature inputs (CLT and IAT). In order to standardise the voltage divider circuit, these should both have a 2490 Ohm resistor - There is no fly back diode on the MOSFETs. Assumption for this board was that protected drivers would always be used, but the provision for a diode should be added for flexiblity.