FreeStim idea
Posted: Sun Sep 01, 2013 7:07 pm
Ok, so I have given this some thought and figured I should share my idea for everyone's benefit and assistance with the development of a FOSS stimulator for DIY ECUs.
My references below are based on the Jaguar schematics.
Andy.
My references below are based on the Jaguar schematics.
- So here is my idea for "FreeStim":
- Use an MC9S12XDP512 112-pin MCU on a removable development board (so it can be used for other things as well) that would plug into the "FreeStim" board. This will allow us to use the FreeEMS benchtest (DEFAULT) firmware along with software like https://github.com/johnhowe/Lacerated-Pempheridae to simulate the RPM0 and RPM1 input patterns via the Port T0 and T1 outputs from the development board.
- Use a TC4427A that would be connected to the T0 and T1outputs from the development board MCU to allow the selection of a 5v or 12 pull up of these inputs to simulate OEM trigger sensors (RPM0 and RPM1 inputs on the ECU).
- Use potentiometers for CHT, IAT, MAF, O2, SPR1 and TPS.
- Have LEDs for High Power LSD outputs (Injectors) 1-8, Medium Power LSD outputs (Fuel Pump, LSD1 and LSD2), 5v (Analog-5v/TPS-5v) output and PWM idle valve output.
- Have a toggle switch on the +12-16vdc (battery connection) input to the onboard regulator.
- Have an onboard LM2940T +5v low dropout regulator with a 0.5A thermal fuse and a power on LED.
- Have an onboard LM7812 +12v regulator to test the BRV input on the ECU with a known value.
- Have 0.100" header strips for +5v, +12v, +12-16v (battery connection) and GND.
- Have a Molex "Mini-Fit, Jr" style connector so that adapters can be easily made by the user to adapt to whatever connector(s) they are using for their FreeEMS or other ECU.
Andy.