MSP430 circuit to measure and trick 1997 Jetta LD Pump
| /* 1997 Volkwagen Jetta LD Pump Circuit tester/bypasser | |
| * Trevor Bentley, September 2011 | |
| * | |
| * | |
| * Operation: | |
| * - Displays welcome message on boot | |
| * - Dumps 256 bytes of Informational Flash (if UART enabled) | |
| * - Enters very low power state while waiting | |
| * - Wakes up when a falling edge detected on P1.4, which should go to | |
| * the power output of the ECM to the LD Pump solenoid. This requires | |
| * extra circuitry. | |
| * - Measures each edge as a 'pump', counts number of pumps. | |
| * - Red LED (P1.0) blinks rapidly while pumping | |
| * - When reach target number of pumps (PUMP_TARGET), green LED (P1.6) | |
| * turns on, and SENSE line is pulled high (P1.5). This is held for | |
| * SENSE_LINE_SECONDS. | |
| * - Measured total number of pumps, and time to reach target number | |
| * of pumps. | |
| * - Red and Green LEDs both on while measurements written to Informational | |
| * Flash. | |
| * - Most recent measurements displayed (if UART enabled) | |
| * - Back to very low power state while waiting. | |
| * | |
| * | |
| * | |
| * EXAMPLE CIRCUIT: | |
| * | |
| * BAT(-)----------------------- | |
| * BAT(+)-----------[3.3REG] | | |
| * | | | | |
| * [C VCC]--|-^^^|--[ opto ]--^^^|----[P1.4 ] | |
| * [A ] _ > [isolator] [ P1.0] - Red LED | |
| * [R ] ^ > [ ] [ P1.6] - Green LED | |
| * [ ] | > [ ] [ ] | |
| * [E GND]--|----|--[ ] [ MSP430] | |
| * [C ] [ ] | |
| * [M SENSE]---^^^-----[transistor]-------[P1.5 ] | |
| * | | | |
| * BAT(+)----^^^-/ \--BAT(-) | |
| * | |
| * | |
| * MSP430 powered by 3.3V regulator off of constant battery power. | |
| * | |
| * Car ECM connects to optoisolator via voltage divider (divide to 3V, | |
| * and current limit). Safety diode from ground to power. Optoisolator | |
| * connects to P1.4, pulled up to constant battery power. Car ECM will | |
| * switch either VCC or GND on and off to pump the LD Pump, which this | |
| * circuit replaces. This will result in toggling on P1.4. | |
| * | |
| * P1.5 controls base of transistor that pulls sense line up to constant | |
| * battery power. | |
| * | |
| */ | |
| #include <msp430x22x2.h> | |
| #include <signal.h> | |
| #include <string.h> | |
| //------------------------------------------------------------------------------ | |
| // Hardware-related definitions | |
| //------------------------------------------------------------------------------ | |
| #define UART_TXD 0x02 // TXD on P1.1 (Timer0_A.OUT0) | |
| #define UART_RXD 0x04 // RXD on P1.2 (Timer0_A.CCI1A) | |
| #define LDPUMP 0x10 // LDPump detect P1.4 | |
| #define SENSE 0x20 // Sense Line P1.5 | |
| #define RED_LED 0x01 // Red LED | |
| #define GREEN_LED 0x40 // Green LED | |
| //#define TEST_VALS | |
| #ifndef TEST_VALS | |
| #define SENSE_LINE_SECONDS 90U // Seconds to hold SENSE line | |
| #define PUMP_TARGET 30U // Number of 'pumps' to detect | |
| #else | |
| #define SENSE_LINE_SECONDS 4U | |
| #define PUMP_TARGET 10U | |
| #endif | |
| #define CLOCK_DIV (10U) | |
| #define MS_PER_TICK (10*CLOCK_DIV) // Milliseconds per clock interrupt | |
| // Number of clock interrupts to hold SENSE line for. | |
| #define SENSE_TICKS (SENSE_LINE_SECONDS * (1000 / MS_PER_TICK)) | |
| // Base address of Informational Flash | |
| #define INFO_FLASH_BASE 0x1000 | |
| //------------------------------------------------------------------------------ | |
| // Conditions for 9600 Baud SW UART, SMCLK = 1MHz | |
| //------------------------------------------------------------------------------ | |
| #define UART_ENABLED | |
| #ifdef UART_ENABLED | |
| #define UART_TBIT_DIV_2 (1000000U / (9600 * 2)) | |
| #define UART_TBIT (1000000U / 9600) | |
| #endif | |
| //------------------------------------------------------------------------------ | |
| // Global variables used for full-duplex UART communication | |
| //------------------------------------------------------------------------------ | |
| #ifdef UART_ENABLED | |
| unsigned int txData = 0; // UART internal variable for TX | |
| unsigned char rxBuffer = 0; // Received UART character | |
| #endif | |
| // Structure for storing measurements | |
| typedef struct { | |
| unsigned int pump_count; | |
| unsigned int timer_count; | |
| } measure_t; | |
| // Number of elements in measurements[] | |
| #define MEASUREMENT_COUNT (64/sizeof(measure_t)) | |
| // Mask for wrapping measurements[] index | |
| #define MEASUREMENT_MASK (MEASUREMENT_COUNT-1) | |
| // Array of measurement readings | |
| measure_t measurements[MEASUREMENT_COUNT]; | |
| // Index of current measurement | |
| unsigned int measurement_idx = 0; | |
| // State machine variable | |
| volatile enum tstate { | |
| WAITING, | |
| PUMPING, | |
| HOLDING, | |
| UARTTX | |
| } timer_state = WAITING; | |
| // LUT for hex characters | |
| unsigned char hexvals[] = { | |
| '0','1','2','3','4','5','6','7', | |
| '8','9','A','B','C','D','E','F', | |
| }; | |
| volatile unsigned int counter = 0; // Timer interrupt ticks | |
| volatile unsigned int toggles = 0; // Toggles of pumps | |
| volatile unsigned int counter_cycles_until_stop = 0; // IRQ ticks until done | |
| //------------------------------------------------------------------------------ | |
| // Function prototypes | |
| //------------------------------------------------------------------------------ | |
| void reset_ldpump(void); | |
| void erase_flash(int addr); | |
| void save_byte(char byte, char flash_offset); | |
| void save_measurements(void); | |
| void end_sense_hold(void); | |
| void TimerA_Counter_init(void); | |
| void Port1_ISR(void); | |
| void Timer_A0_ISR(void); | |
| #ifdef UART_ENABLED | |
| void print_values(void); | |
| void uart_isr(void); | |
| void TimerA_UART_init(void); | |
| void TimerA_UART_tx(unsigned char byte); | |
| void TimerA_UART_print(char *string); | |
| void TimerB_ISR(void); | |
| #endif | |
| //------------------------------------------------------------------------------ | |
| // main() | |
| //------------------------------------------------------------------------------ | |
| void main(void) | |
| { | |
| #ifdef UART_ENABLED | |
| int temp; | |
| int i; | |
| char str[4]; | |
| #endif | |
| // Configure clocks | |
| WDTCTL = WDTPW | WDTHOLD; // Stop watchdog timer | |
| DCOCTL = 0x00; // Set DCOCLK to 1MHz | |
| BCSCTL1 = CALBC1_1MHZ; | |
| DCOCTL = CALDCO_1MHZ; | |
| // Configure Port 1 | |
| P1OUT = 0x00; // Initialize all GPIO | |
| P1DIR = 0xFF & ~(UART_RXD | LDPUMP); // Set all pins but RXD to output | |
| #ifdef UART_ENABLED | |
| P1SEL = UART_TXD | UART_RXD; // Timer function for TXD/RXD pins | |
| #endif | |
| // P1.4 is interrupt -- LD Pump solenoid line | |
| P1IE = 0x10; // Turn on P1.4 interrupts | |
| P1IES = 0x10; // High->low edge detect | |
| P1REN = 0x10; // Pull-down resistor enabled | |
| // Clear measurements | |
| memset(measurements, 0xFF, sizeof(measurements)); | |
| eint(); // Enable interrupts | |
| #ifdef UART_ENABLED | |
| // Print 256-bytes of informational flash | |
| TimerA_UART_init(); | |
| TimerA_UART_print("\r\nLDP-TEST\r\n"); | |
| str[2] = ' '; | |
| str[3] = 0; | |
| for (i = 0; i < 256; i++) { | |
| temp = *((volatile char*)INFO_FLASH_BASE+i); | |
| str[0] = hexvals[temp >> 4 & 0xF]; | |
| str[1] = hexvals[temp & 0xF]; | |
| TimerA_UART_print(str); | |
| } | |
| TimerA_UART_print("\r\n$$$%%%$$$\r\n\r\n"); | |
| #endif | |
| // Enable pump detector | |
| TimerA_Counter_init(); | |
| for (;;) | |
| { | |
| // Sleep in super-low-power-mode | |
| LPM3; | |
| // Go to moderate-low-power-mode after PIO wakes us up | |
| LPM0; | |
| // Awoken after a pump session has finished and written to flash. | |
| // Print status (if enabled), and reset state machine | |
| #ifdef UART_ENABLED | |
| print_values(); | |
| #endif | |
| reset_ldpump(); | |
| } | |
| } | |
| // Write entire 'measurements' variable to information flash (erases first) | |
| // Manages interrupts itself. Do NOT disable. | |
| void save_measurements(void) { | |
| int i; | |
| static int count = 0; | |
| static int offset = 0; | |
| unsigned char *p = (unsigned char*)measurements; | |
| dint(); | |
| FCTL3 = FWKEY; // Unlock | |
| FCTL1 = FWKEY | ERASE ; // Erase | |
| *((volatile char*)(INFO_FLASH_BASE + offset)) = 0; | |
| FCTL1 = FWKEY | WRT; // Write | |
| memcpy((void*)(INFO_FLASH_BASE + offset + i), p, | |
| sizeof(measurements)); | |
| FCTL1 = FWKEY; // No-op | |
| FCTL3 = FWKEY | LOCK; // Lock | |
| // If we've written a full block... | |
| if (++count == MEASUREMENT_COUNT) { | |
| count = 0; | |
| // Clear measurements | |
| memset(measurements, 0xFF, sizeof(measurements)); | |
| // Next time, write to next block of FLASH. We have 3 64-byte blocks. | |
| offset += 0x40; | |
| if (offset == 0xc0) offset = 0; | |
| } | |
| eint(); | |
| } | |
| void reset_ldpump(void) { | |
| // Reset counters and state | |
| counter = 0; | |
| toggles = 0; | |
| counter_cycles_until_stop = 0; | |
| timer_state = WAITING; | |
| P1OUT &= ~(RED_LED | GREEN_LED | SENSE); // Disable lights and sense | |
| } | |
| //------------------------------------------------------------------------------ | |
| // Turn on timer, interrupt ticks every 10ms | |
| // Interrupt shared with UART, so only one can be enabled at a time. | |
| //------------------------------------------------------------------------------ | |
| void TimerA_Counter_init(void) { | |
| // Configure Timer_A | |
| // Internal 1MHz timer divided by 8 (ID_3) == 125000 / s | |
| // (12500 ticks/s) / 100 == 1250 ticks per 10 ms | |
| // One interrupt per 10*CLOCK_DIV ms. | |
| TACTL = MC_0; // Disable timer | |
| TACCR0 = 1250*CLOCK_DIV; // ticks per interrupt | |
| TACCTL0 = CCIE | OUTMOD_7; // Enable interrupts, reset on overflow | |
| timer_state = WAITING; | |
| TACTL = TASSEL_2 | MC_1 | TACLR | ID_3; // Set to 1MHz clock, turn on | |
| } | |
| //------------------------------------------------------------------------------ | |
| // Interrupt when edge detected on P1.4, signifying switching | |
| // on LD Pump solenoid line. | |
| //------------------------------------------------------------------------------ | |
| interrupt(PORT1_VECTOR) Port1_ISR(void) { | |
| if (timer_state == WAITING) { | |
| // We were waiting in super-low-power mode. Wake up! | |
| LPM3_EXIT; | |
| // No longer waiting, it's pump time | |
| timer_state = PUMPING; | |
| } | |
| else if (++toggles == PUMP_TARGET) { | |
| // We reached our target number of pumps, so trigger SENSE line. | |
| P1OUT |= SENSE | GREEN_LED; | |
| P1OUT &= ~(RED_LED); | |
| counter_cycles_until_stop = SENSE_TICKS; | |
| timer_state = HOLDING; | |
| } | |
| P1IFG = 0x00; | |
| } | |
| void end_sense_hold(void) { | |
| volatile int i; | |
| P1OUT |= RED_LED; | |
| measurements[measurement_idx].pump_count = toggles; | |
| measurements[measurement_idx].timer_count = counter; | |
| measurement_idx = (measurement_idx + 1) & MEASUREMENT_MASK; | |
| save_measurements(); | |
| P1OUT &= ~RED_LED; | |
| } | |
| //------------------------------------------------------------------------------ | |
| // Timer_A UART - Transmit Interrupt Handler | |
| //------------------------------------------------------------------------------ | |
| enablenested interrupt (TIMERA0_VECTOR) Timer_A0_ISR(void) | |
| { | |
| static unsigned char txBitCnt = 10; | |
| switch (timer_state) { | |
| case WAITING: // Waiting to detect first pump from ECM | |
| break; | |
| case PUMPING: // Pumps detected, counting to target number | |
| // Increment counter, toggle LED | |
| if (++counter) | |
| P1OUT ^= RED_LED; | |
| break; | |
| case HOLDING: // Target number of pumps reached, holding SENSE line | |
| if (--counter_cycles_until_stop == 0) { | |
| end_sense_hold(); | |
| // Wake up main. It will print status and reset state machine | |
| LPM0_EXIT; | |
| } | |
| break; | |
| #ifdef UART_ENABLED | |
| case UARTTX: | |
| goto uart; | |
| #endif | |
| default: | |
| break; | |
| } | |
| return; | |
| #ifdef UART_ENABLED | |
| uart: | |
| TACCR0 += UART_TBIT; // Add Offset to CCRx | |
| if (txBitCnt == 0) { // All bits TXed? | |
| TACCTL0 &= ~CCIE; // All bits TXed, disable interrupt | |
| txBitCnt = 10; // Re-load bit counter | |
| } | |
| else { | |
| if (txData & 0x01) { | |
| TACCTL0 &= ~OUTMOD2; // TX Mark '1' | |
| } | |
| else { | |
| TACCTL0 |= OUTMOD2; // TX Space '0' | |
| } | |
| txData >>= 1; | |
| txBitCnt--; | |
| } | |
| #endif | |
| } | |
| #ifdef UART_ENABLED | |
| void print_values(void) { | |
| unsigned char mstr[10]; | |
| TimerA_UART_init(); | |
| mstr[0] = hexvals[toggles >> 12 & 0xF]; | |
| mstr[1] = hexvals[toggles >> 8 & 0xF]; | |
| mstr[2] = hexvals[toggles >> 4 & 0xF]; | |
| mstr[3] = hexvals[toggles & 0xF]; | |
| mstr[4] = ' '; | |
| mstr[5] = hexvals[counter >> 12 & 0xf]; | |
| mstr[6] = hexvals[counter >> 8 & 0xF]; | |
| mstr[7] = hexvals[counter >> 4 & 0xF]; | |
| mstr[8] = hexvals[counter & 0xF]; | |
| mstr[9] = 0; | |
| TimerA_UART_print(mstr); | |
| TimerA_UART_print("\r\n\r\n"); | |
| TimerA_Counter_init(); | |
| } | |
| //------------------------------------------------------------------------------ | |
| // Function configures Timer_A for full-duplex UART operation | |
| //------------------------------------------------------------------------------ | |
| void TimerA_UART_init(void) | |
| { | |
| TACTL = MC_0; // Disable timer | |
| TACCTL0 = OUT; // Set TXD Idle as Mark = '1' | |
| TACCTL1 = SCS + CM1 + CAP + CCIE; // Sync, Neg Edge, Capture, Int | |
| timer_state = UARTTX; | |
| TACTL = TASSEL_2 + MC_2 + TACLR; // SMCLK, start in continuous mode | |
| } | |
| //------------------------------------------------------------------------------ | |
| // Outputs one byte using the Timer_A UART | |
| //------------------------------------------------------------------------------ | |
| void TimerA_UART_tx(unsigned char byte) | |
| { | |
| while (TACCTL0 & CCIE); // Ensure last char got TX'd | |
| TACCR0 = TAR; // Current state of TA counter | |
| TACCR0 += UART_TBIT; // One bit time till first bit | |
| TACCTL0 = OUTMOD0 + CCIE; // Set TXD on EQU0, Int | |
| txData = byte; // Load global variable | |
| txData |= 0x100; // Add mark stop bit to TXData | |
| txData <<= 1; // Add space start bit | |
| } | |
| //------------------------------------------------------------------------------ | |
| // Prints a string over using the Timer_A UART | |
| //------------------------------------------------------------------------------ | |
| void TimerA_UART_print(char *string) | |
| { | |
| while (*string) { | |
| TimerA_UART_tx(*string++); | |
| } | |
| } | |
| //------------------------------------------------------------------------------ | |
| // Timer_A UART - Receive Interrupt Handler | |
| //------------------------------------------------------------------------------ | |
| interrupt (TIMERA1_VECTOR) Timer_A1_ISR(void) | |
| { | |
| } | |
| //------------------------------------------------------------------------------ | |
| #endif //UART_ENABLED |
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