.LOG Fuel Injection Board 9:50 AM 5/25/2007 Note: The connectors are not numbered so I'm not sure whether to number them from right to left or left to right. Components: IC1 - SX28 (MCU) pin 18, RC.0 test point pin 19, RC.1 test point IC2 - PCF8591 (I2C A/D. 5V) IC3 - PCF8591 (I2C A/D, 2.5V) unknown destination for pin 13 IC4 - MOSFET MIC4422 IC5 - MOSFET MIC4422 IC6 - MOSFET MIC4422 IC7 - MOSFET MIC4422 IC8 - 24C32 I2C 4K EEPROM, need to determine I2C address from code **** this eeprom has built in address, the a0-a3 are not connected Clock - Transko SXO-550-H-100-ET http://www.transko.com/catalog_pdf/catalog_pdf_7-10-05/oscillators/pdf/sxo.pdf **** also on the clock connector if you pull that off you can plug the sx-key directly into it for programing, thay why thier are somany wires running around the pins Q1 - KA317 (Adjustable Voltage Regulator) Q2 - 7805 or LM2940 (5V Voltage Regulator) Q3 - Transistor, 2N3906? - not sure of its purpose *** A1015 for powering the seiral output D1 - Diode 1N4001 R1 - 4.7K pull-up resistor for I2C network SDA (SX28, RC.6) R2 - 4.7K pull-up resistor for I2C network SCL (SX28, RC.7) R4 - ??? used with R22, pull-up for IC3,pin13 *** R4 is 1K, used with R22 for pullup and to drop voltage to 2.5 volts for refernce R5 - ??? used with Q3 transistor *** 33K, used to lower serial input power from computer R6 - ?72 used to adjust voltage on Q1 *** 8.2K R7 - ?72 used to adjust voltage on Q1 *** 1.5K R9 - 10K, pull-up for SX28 MCLR R10 - 6.6K, pull-up for SX28 pin 21 **** used for Hall sensor input pullup R11 - 6.6K, pull-up for SX28, pin 22 **** used for Hall sensor input pullup R22 - 1K used with R4, pull-up for IC3,pin13 C1 - 100uf? - voltage regulation *** 4.7uf C2 - 100uf? - voltage regulation *** 33uF C3 - 100uf? - voltage regulation *** 1000uF ****C4 .22uf RB1 - Connector to SX28 Port B pins AN1 - Connector *** for analog inputs SIL3 - Connector (presumably power in) SIL4 - connector (A OUT) **** power to injectors and ignition PW1 - selects power source (direct or 5V?), can't figure out where pin 2 goes to. *** pin 2 is ground, this powers all the sensors on the engin, some run at 5 volts other at 12 volts JP1 - selects between IC4 and IC5 *** selects either to both run off of one input or both to run serperatly JP2 - selects between IC6 and IC7 *** selects either to both run off of one input or both to run serperatly SR8 - selects between transistor base and SX28 pins RC4,5? *** this is the serial inout to the computer pin 3 is out goes to 3pin on rs232 pin2 is ground goes to pin 5 on rs232 and pin 1 is in from pin 2 on rs232 SL1? - looks like a test point *** this is for the Hall sensor input also thier is a connector for rc1 and rc0, pins 19 and 18 for a test point. 1:05 PM 5/25/2007