This will cover the development of a new ECU based on the Microsquirt module using the Cinch SE enclosure with the 48-pin connectors together with a board to carry the module and having an auxiliary CPU (mini IOx) to control additional I/Os and features based on the I/O Extender code and features.
The features and pin usage as of now are as follows:
- 4 pins for high Z injector drivers (2 on the module and 2 on the new board)
- 4 pins for logic coil drivers
- 6 pins for 2 differential VR inputs (VR+ and VR-) which can be configured as opto/Hall inputs with one pin per input used for pull up or shunt depending on how it is connected
- 4 pins 2 RS-232 serial ports (Microsquirt module and mini IOx)
- 2 pins for the CAN bus (for both Microsquirt module and mini IOx)
- 2 pins for main power supply: 12V and ground (may need to double that to reduce noise)
- 1 pin MAT
- 1 pin CLT
- 1 pin TPS
- 2 pins for 2 O2 sensors
- 1 pin Vref
- 2 pins for idle control: either 3-wire valve or 2-wire valve plus one spare output
- 1 pin fuel pump
- 2 pins MAP+Baro
- 1 pin bootload
- 1 pin Tach output
- 1 pin table switching
- 1 pin launch control
- 1 pin boost control
- 3 pins NOS (1 input + 2 outputs)
- 2 pins programmable outputs (may need to remove these if additional 12V and ground needed)
- 2 pin analog inputs (may need to remove these instead of programmable outputs if additional 12V and ground needed)
- 3 pins ground: 1 sensor ground + 2 high current grounds
The inputs will be configured to use the Microsquirt module circuit directly except for the tach inputs which will use a MAX9926 interface and the few optional inputs which will use an active low input circuit. The outputs will use the standard Microsquirt module circuits except for the ignition outputs which will use the pushpull circuit discussed recently on the MS3 forum (to allow the use of most, if not all, "logic level" COPs) and optional outputs which will use an appropriate driver for the feature. The mini IOx serial port could be used for reading the digital data from an LC1 chain (or other WBO2 serial controller protocols yet to be implemented such as PLX and TechEdge); this will free one ADC input.
I'll update this as things progress. If you have any preference on the aforementioned options in case some I/Os need to be cut, post you comments.
The planned number of units for the initial release is from 6 to 8. If you have an interest in having one, please mention it here (24c and tmsmini have expressed their interest). Depending on the interest, there may be some future development and more units or these may be the only units produced. I'll confirm a price target as more data becomes available.