MegaShift GPIO Port and Pin Assignments
The GPIO processor has 25 free pins available for inputs and outputs (I/O) (not including the serial and CANbus communications pins), and 25 PCB I/O circuits available.
The microTCU™ pins are a bit different, see this link for information on the microTCU™ differences.
The default assignments for the GPIO pins are:
Default Function | Port/Pin | (I)nput or (O)utput | Default Circuit Assignment (Ampseal Pin) | Alternate Functions | Notes:
|
VSS | PT0 | I | VR1 (Amp 2) | <-none-> | Vehicle speed signal input, interrupt driven |
ISS | PT5 | I | VR3 (Amp 14) | Engine speed (tachometer) input | Input shaft speed sensor or tach input, interrupt driven |
PC | PT2 | O | PWM3 (Amp 33) | Spare Output3/Output9 (5.1xx code only) | Line pressure control output on PWM2 |
TCC | PT3 | O | PWM2 (Amp 32) | <-none-> | Dedicated torque converter clutch control output on PWM3 |
Output1 | PE4 | O | VB3 (Amp 23) | <-none-> | Dedicated shift solenoid output #1 |
Output2 | PM2 | O | VB4 (Amp 35) | <-none-> | Dedicated shift solenoid output #2 |
Output3 | PT1 | O | PWM4 (Amp 34) | <-none-> | Dedicated shift solenoid output #3 |
Shift Lever Input1 (digital) | PAD00 * | I | EGT4 (build as GPI) (Amp 26) | Voltage lever input | ADC count for shift lever position input #1 |
Shift Lever Input2 (digital) | PAD01 * | I | GPI2 (jumper at 25x2 header) (Amp 6) | Output5 | ADC count for shift lever position input #2 |
Shift Lever Input3 (digital) | PAD03 * | I | EGT3 (Amp 25) | Output6 | ADC count for shift lever position input #3 |
Paddle UP | PT6 | I | VR2 (build as digital input) (Amp 15) | <-none-> | Digital on/off input for up-shifting |
Paddle DOWN | PAD06 * | I | GPI5 (Amp 4) | Voltage shifter buttons | On/off input for down-shifting, but can be an ADC input |
LED1 | PM4 | O | GPO1 (Amp 10) | 7-segment display | Low current output |
LED2 | PM3 | O | GPO2 (Amp 7) | 7-segment display | Low current output |
LED3 | PM5 | O | GPO3 (Amp 8) | 7-segment display | Low current output |
LED4 | PB4 | O | GPO4 (Amp 9) | 7-segment display | Low current output |
Brake Sense | PAD07 | I | GPI4 (Amp 3) | <-none-> | Digital on/off input |
non-CANbus MAP/TPS/MAF | PAD05 * | I | EGT1 (Amp 24) | Report auxiliary variable voltage signal level as aux_volts (if using CANbus) | ADC count |
Line Pressure Sensor | PAD04 * | I | EGT2 (Amp 27) | Optional logging only | ADC count |
Temperature Sensor | PAD02 * | I | GPI3 (Amp 30) | Optional logging only | ADC count |
Speedo Output | PT4 | O | PWM1 (Amp 31) | Spare 0utput0/Output8 | |
4WD Input | PE1 | I | GPI1 (Amp 5) | shift table switching/Shift lever Input 4 | Digital on/off input for switching between shift table 1 and shift table 2 |
Spare Output1 | PT7 (Amp 2) | O | VB1 (jumper at 25x2 header) (Amp 11) | Output7 | User Spare Port, PWM, TCC, Shift Solenoid, or Selective Clutch. |
Spare Output2 | PA0 | O | VB2 (Amp 12) | Output4 | User Spare Port, PWM, TCC, Shift Solenoid, or Selective Clutch. |
Pin PE0 and circuit VR4 are not assigned in the default builds (but these are available on the 25x2 header, of course).
The "OutputX" label (Output1, Output2, etc.) has been restricted to pins that can be used as shift solenoid outputs. These outputs have a user specified state for each gear to shift the transmission between gears. There are other types of outputs, of course, such as TCC, PC, speedo output signal, etc. but these are labeled differently.
"InputX" refers to manual shift lever position signal digital inputs. There are other types of inputs, of course, such as VSS, temperature, brake, etc. but these are labeled differently.
Spare Outputs are outputs that have multiple user configurable functions (including possible use as shift solenoid control outputs). See this web page for more details.
* The analog-digital converter pins PAD00 to PAD07 are also know as ADX, AD0X, etc., but are never referenced as PA00 or PA0 as there is an separate port A on the HCS12 processors.