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Hi all, thanks in advance for reading. I am interfacing the PIC32MX320F128H with the MPU6050 over I2C. For some reason my program hangs when I try to initiate a start condition through I2C using plib. More specifically, when I call I2CGetStatus, the I2C_STATUS never returns I2C_START. Without changing the program on the microcontroller, I can get the program to work by doing a hack I've discovered. I unplug my microcontroller from power, I hold the reset button on the microcontroller, plug in the power, and release the reset button, and then my program runs fine. I get values from my accelerometer and gyroscope on the device. But then after reading from the device, I try to initiate a stop condition with I2CStop, but I get no I2C_STOP condition when I call I2CGetStatus afterwards. So I'm starting to think my original issue is related to my issue I get even when I use my workaround. I'm using the MPU6050 from sparkfun. https://www.sparkfun.com/products/11028 My schematic is very simple. VDD - 3.3v from microcontroller GND - GND from microcontroller SCL - A5 SDA - A4 VIO - 3.3v from microcontroller I have been looking at the power on procedure as listed on page 23 of 52 on the datasheet. https://www.cdiweb.com/datasheets/invensense/MPU-6050_DataSheet_V3%204.pdf I have hooked up my VDD and VIO lines to the oscilloscope, and I have looked at both cases when I use my workaround and normal power up, I don't see anything different, so I am very lost. I have successfully been able to interface and use the HMC5883L so I know how I2C works, and I know my I2C library works. But here is my code anyway. main.c #include "xc.h" #include <stdio.h> #include "serial.h" #include "BOARD.h" #include "IO_Ports.h" #include "I2Cpic32.h" #include <plib.h> #define SYS_CLOCK 80000000 #define SLV_CLOCK 400000 #define SLV_ADDR 0x68 #define DELAY(x) for (wait = 0; wait <= x; wait++) {asm("nop");} #define A_BIT 183000 #define A_LOT 18300000 int wait; int main(void) { int p_size, id; UINT32 actualClock; UINT8 packet[10], read_data[14]; uint8_t powerManagementReg; INT16 AcX, AcY, AcZ, GyX, GyY, GyZ, temp; // temp is temperature I2C_7_BIT_ADDRESS slave7BitAddress; DELAY(A_BIT); BOARD_Init(); printf("Board initialized\n"); DELAY(A_LOT); actualClock = I2CSetFrequency(I2C1, SYS_CLOCK, SLV_CLOCK); if ( abs(actualClock-SLV_CLOCK) > SLV_CLOCK/10 ) printf("Error: I2C1 clock frequency (%u) error exceeds 10%%.\n", (unsigned)actualClock); printf("Clock set: %u\n", actualClock); I2CEnable(I2C1, TRUE); printf("I2C Enabled\n"); DELAY(A_LOT); I2C_FORMAT_7_BIT_ADDRESS(slave7BitAddress, SLV_ADDR, I2C_WRITE); DELAY(A_BIT); // wakes up the MPU packet[0] = slave7BitAddress.byte; packet[1] = 0x6b; packet[2] = 0x00; p_size = 3; send_packet(packet, p_size); // gyro config packet[1] = 0x1b; packet[2] = 0x08; send_packet(packet, p_size); // sample rate config packet[1] = 0x19; packet[2] = 0x07; send_packet(packet, p_size); DELAY(A_LOT); for (; { I2C_FORMAT_7_BIT_ADDRESS(slave7BitAddress, SLV_ADDR, I2C_WRITE); packet[0] = slave7BitAddress.byte; packet[1] = 0x3b; p_size = 2; send_packet(packet, p_size); StartTransfer(FALSE); I2C_FORMAT_7_BIT_ADDRESS(slave7BitAddress, SLV_ADDR, I2C_READ); TransmitOneByte(slave7BitAddress.byte); read_data[0] = read_byte(I2C1); // ACCEL_XOUT[15:8] read_data[1] = read_byte(I2C1); // ACCEL_XOUT[7:0] read_data[2] = read_byte(I2C1); // ACCEL_YOUT[15:8] read_data[3] = read_byte(I2C1); // ACCEL_YOUT[7:0] read_data[4] = read_byte(I2C1); // ACCEL_ZOUT[15:8] read_data[5] = read_byte(I2C1); // ACCEL_ZOUT[7:0] read_data[6] = read_byte(I2C1); // TEMP_OUT[15:8] read_data[7] = read_byte(I2C1); // TEMP_OUT[7:0] read_data[8] = read_byte(I2C1); // GYRO_XOUT[15:8] read_data[9] = read_byte(I2C1); // GYRO_XOUT[7:0] read_data[10] = read_byte(I2C1); // GYRO_YOUT[15:8] read_data[11] = read_byte(I2C1); // GYRO_YOUT[7:0] read_data[12] = read_byte(I2C1); // GYRO_ZOUT[15:8] read_data[13] = read_byte(I2C1); // GYRO_ZOUT[7:0] AcX = (read_data[0] << 8) | read_data[1]; AcY = (read_data[2] << 8) | read_data[3]; AcZ = (read_data[4] << 8) | read_data[5]; temp = (read_data[6] << 8) | read_data[7]; GyX = (read_data[8] << 8) | read_data[9]; GyY = (read_data[10] << 8) | read_data[11]; GyZ = (read_data[12] << 8) | read_data[13]; printf("AcX: %d\n", AcX); printf("AcY: %d\n", AcY); printf("AcZ: %d\n", AcZ); printf("temp: %d\n", temp); printf("GyX: %d\n", GyX); printf("GyY: %d\n", GyY); printf("GyZ: %d\n", GyZ); check_status(I2C1); StopTransfer(); DELAY(A_LOT); } return 0; } I2Cpic32.c // Standard headers #include <stdbool.h> #include <stdint.h> // Microchip headers #include <xc.h> #include <plib.h> // User headers #include "I2Cpic32.h" BOOL ret; I2C_RESULT res; BOOL StartTransfer( BOOL restart ) { I2C_STATUS status; // Send the Start (or Restart) signal if(restart) { I2CRepeatStart(I2C1); } else { // Wait for the bus to be idle, then start the transfer while( !I2CBusIsIdle(I2C1) ); if(I2CStart(I2C1) != I2C_SUCCESS) { printf("Error: Bus collision during transfer Start\n"); return FALSE; } } // Wait for the signal to complete do { status = I2CGetStatus(I2C1); } while ( !(status & I2C_START) ); return TRUE; } BOOL TransmitOneByte( UINT8 data ) { // Wait for the transmitter to be ready while(!I2CTransmitterIsReady(I2C1)); // Transmit the byte if(I2CSendByte(I2C1, data) == I2C_MASTER_BUS_COLLISION) { printf("Error: I2C Master Bus Collision\n"); return FALSE; } // Wait for the transmission to finish while(!I2CTransmissionHasCompleted(I2C1)); return TRUE; } void StopTransfer( void ) { I2C_STATUS status; // Send the Stop signal I2CStop(I2C1); // Wait for the signal to complete do { status = I2CGetStatus(I2C1); printf("asuh\n"); } while ( !(status & I2C_STOP) ); } void check_status(I2C_MODULE id) { I2C_STATUS stat = I2CGetStatus(id); if (stat&I2C_TRANSMITTER_FULL) printf("check_status: I2C_TRANSMITTER_FULL\n"); if (stat&I2C_DATA_AVAILABLE) printf("check_status: I2C_DATA_AVAILABLE\n"); if (stat&I2C_SLAVE_READ) printf("check_status: I2C_SLAVE_READ\n"); if (stat&I2C_START) printf("check_status: I2C_START\n"); if (stat&I2C_STOP) printf("check_status: I2C_STOP\n"); if (stat&I2C_SLAVE_DATA) printf("check_status: I2C_SLAVE_DATA\n"); if (stat&I2C_RECEIVER_OVERFLOW) printf("check_status: I2C_RECEIVER_OVERFLOW\n"); if (stat&I2C_TRANSMITTER_OVERFLOW) printf("check_status: I2C_TRANSMITTER_OVERFLOW\n"); if (stat&I2C_10BIT_ADDRESS) printf("check_status: I2C_10BIT_ADDRESS\n"); if (stat&I2C_GENERAL_CALL) printf("check_status: I2C_GENERAL_CALL\n"); if (stat&I2C_ARBITRATION_LOSS) printf("check_status: I2C_ARBITRATION_LOSS\n"); if (stat&I2C_TRANSMITTER_BUSY) printf("check_status: I2C_TRANSMITTER_BUSY\n"); if (stat&I2C_BYTE_ACKNOWLEDGED) printf("check_status: I2C_BYTE_ACKNOWLEDGED\n"); } BYTE read_byte(I2C_MODULE id) { BYTE val; ret = I2CReceiverEnable(I2C1, TRUE); //printf("I2CReceiverEnable(I2C1, TRUE): %d\n", ret); while(!(ret = I2CReceivedDataIsAvailable(I2C1))); ret = I2CReceivedDataIsAvailable(I2C1); //printf("I2CReceivedDataIsAvailable(I2C1): %d\n", ret); I2CAcknowledgeByte(I2C1, TRUE); val = I2CGetByte(id); //printf("val: %x\n", val); while(!(ret = I2CAcknowledgeHasCompleted(I2C1))); //printf("I2CAcknowledgeHasCompleted(I2C1): %d\n", ret); return val; } void send_packet(UINT8 data[], int size) { int i; // Start transfer ret = StartTransfer(FALSE); //printf("StartTransfer(FALSE): %d\n", ret); for (i = 0; i < size; i++) { ret = TransmitOneByte(data[i]); //printf("TransmitOneByte(%x): %d\n", data[i], ret); ret = I2CByteWasAcknowledged(I2C1); //printf("I2CByteWasAcknowledged(I2C1): %d\n", ret); } // Stop transfer StopTransfer(); } uint8_t I2C_ReadReg(uint8_t address, uint8_t reg) { uint8_t val; printf("asuh\n"); StartTransfer(FALSE); ret = TransmitOneByte(address << 1); printf("TransmitOneByte(%x): %d\n", (address << 1), ret); ret = I2CByteWasAcknowledged(I2C1); printf("I2CByteWasAcknowledged(I2C1): %d\n", ret); ret = TransmitOneByte(reg); printf("TransmitOneByte(%x): %d\n", reg, ret); ret = I2CByteWasAcknowledged(I2C1); printf("I2CByteWasAcknowledged(I2C1): %d\n", ret); StartTransfer(TRUE); ret = TransmitOneByte((address << 1) + 1); printf("TransmitOneByte(%x): %d\n", ((address << 1) + 1), ret); ret = I2CReceiverEnable(I2C1, TRUE); printf("I2CReceiverEnable(I2C1, TRUE): %d\n", ret); while(!(ret = I2CReceivedDataIsAvailable(I2C1))); ret = I2CReceivedDataIsAvailable(I2C1); val = I2CGetByte(I2C1); printf("val: %x\n", val); StopTransfer(); return val; } int16_t I2C_ReadReg16(uint8_t address, uint8_t reg) { int16_t val; StartTransfer(FALSE); ret = TransmitOneByte(address << 1); printf("TransmitOneByte(%x): %d\n", (address << 1), ret); ret = I2CByteWasAcknowledged(I2C1); //printf("I2CByteWasAcknowledged(I2C1): %d\n", ret); ret = TransmitOneByte(reg); printf("TransmitOneByte(%x): %d\n", reg, ret); ret = I2CByteWasAcknowledged(I2C1); //printf("I2CByteWasAcknowledged(I2C1): %d\n", ret); StartTransfer(TRUE); ret = TransmitOneByte((address << 1) + 1); printf("TransmitOneByte(%x): %d\n", ((address << 1) + 1), ret); ret = I2CReceiverEnable(I2C1, TRUE); //printf("I2CReceiverEnable(I2C1, TRUE): %d\n", ret); while(!(ret = I2CReceivedDataIsAvailable(I2C1))); ret = I2CReceivedDataIsAvailable(I2C1); val = I2CGetByte(I2C1) << 8; ret = I2CReceiverEnable(I2C1, TRUE); //printf("I2CReceiverEnable(I2C1, TRUE): %d\n", ret); while(!(ret = I2CReceivedDataIsAvailable(I2C1))); ret = I2CReceivedDataIsAvailable(I2C1); val |= I2CGetByte(I2C1); printf("val: %x\n", val); StopTransfer(); return val; } void I2C_WriteReg(UINT8 address, UINT8 reg, UINT8 val) { // Start transfer ret = StartTransfer(FALSE); //printf("StartTransfer(FALSE): %d\n", ret); ret = TransmitOneByte(address); //printf("TransmitOneByte(%x): %d\n", address, ret); ret = I2CByteWasAcknowledged(I2C1); //printf("I2CByteWasAcknowledged(I2C1): %d\n", ret); ret = TransmitOneByte(reg); //printf("TransmitOneByte(%x): %d\n", reg, ret); ret = I2CByteWasAcknowledged(I2C1); //printf("I2CByteWasAcknowledged(I2C1): %d\n", ret); ret = TransmitOneByte(val); //printf("TransmitOneByte(%x): %d\n", val, ret); ret = I2CByteWasAcknowledged(I2C1); //printf("I2CByteWasAcknowledged(I2C1): %d\n", ret); // Stop transfer StopTransfer(); }

Hi everyone, I have been playing with a MPU6050 and an Arduino for a while now and I think it time to replace my Arduino with my new pic32mx. I d like to create a "bridge" in order to use the I2Cdev library on a pic. First of all, if I managed to miss it during my google search, I would love the link If not, well, I m willing to try and build it myself. However I could use some guidelines... I would not say I m a noob in programming but I m certainly not an expert. The way I understand it: All the Class in this library use functions coming from "I2Cdev.cpp/h" "I2Cdev" is using functions coming from "Wire.cpp/h" (I know there is other possibilities but It can work using only the Wire class correct?) Then "Wire" use "twi.cpp/h" (with the TwoWire object created outside of the class ?!? (extern TwoWire Wire;) that's where c++ starts to be a bit confusing for me...) My first (and still main) idea was to create a whole new "Wire.cpp" and to rewrite all its original functions with code appropriate to pic32. But an other option could be to keep the Wire classe from Arduino and rewrite the TWI class instead... The second option would permit to keep the twi class almost intact (with all its benefit) and change only the necessary part. Third option : Anyone ??? What I have today is a class with the following functions (working for my pic) sendStart (bool restart) send a start or a restart signal sendStop() send a stop signal transmitOneByte(char data) just put a byte in the buffer (hardware send it automatically) sendData(char *data, int quantity) // Call sendStart // transmit *data with data[0] = slave address // Call sendStop readData(char *dataTX, int nb param, char *dataRX, int quantity) // Call sendStart // transmit *data with data[0] = slave address, data[1] = register1 , data[2] = register 2 .... // sendStart restart // transmit slave address+write // read the different byte, store them in dataRX and send a Nack at the end // Call sendStop I believe they are close to the Wire class so that should be the easy option however Wire is a daughter class of Stream.h which is daughter of print.h which is daughter......... So the really easy option would be to download that library from a dark website in one of your post below ;-) ;-) ;-) Looking forward to reading you Joachim