//------------------------------------------------------------------------------
// Writes a byte to I2C and checks acknowledge
// returns 0 on success
//------------------------------------------------------------------------------
i2cError_t i2cSoftWriteByte(uint8_t txByte)
{
uint8_t mask;
i2cError_t err=0;
for (mask = 0x80; mask > 0; mask >>= 1) //shift bit for masking (8 times)
{
if ((mask & txByte) == 0) {
I2C_SDA_LO(); //write a bit to SDA-Line
}
else {
I2C_SDA_HI();
}
udelay(1);
I2C_SCL_HI();
udelay(5);
I2C_SCL_LO();
udelay(1);
}
I2C_SDA_IN(); //release SDA-line
I2C_SCL_HI(); //clk #9 for ack
udelay(5);
if (I2C_SDA_GET() != 0) {
err = I2C_ACK_ERROR; //check ack from i2c slave
}
I2C_SCL_LO();
udelay(5);
//udelay(20); //delay to see the package on scope
I2C_SDA_OUT();
return err; //return error code
}
//------------------------------------------------------------------------------
// Reads a byte from I2C
// Returns the byte received
// note: timing (delay) may have to be changed for different microcontroller
//------------------------------------------------------------------------------
uint8_t i2cSoftReadByte(i2cAck_t ack)
{
uint8_t mask, rxByte=0;
I2C_SDA_IN(); //release SDA-line
for (mask = 0x80; mask > 0; mask >>= 1) //shift bit for masking
{
I2C_SCL_HI(); //start clock on SCL-line
udelay(4);
if (I2C_SDA_GET() != 0) {
rxByte = (rxByte | mask); //read bit
}
I2C_SCL_LO();
udelay(1); //data hold time
}
if (ack) {
I2C_SDA_LO(); //send acknowledge if necessary
} else {
I2C_SDA_HI();
}
udelay(1);
I2C_SCL_HI(); //clk #9 for ack
udelay(5);
I2C_SCL_LO();
I2C_SDA_IN(); //release SDA-line
udelay(5);
//udelay(20); //delay to see the package on scope
return rxByte; //return received byte
}
/*
* Toggles in a single byte in master mode.
*
* Entry: SCL low, SDA any
* Exit: SCL low, SDA low with ack set, high else
*
* Change SDA only when SCL is low!
* Sample SDA short before setting SCL low!
*/
static uint8_t TwGet(GPIO_TWICB* icb, uint8_t ack)
{
uint8_t rc = 0;
int i;
/* SDA is input. */
I2C_SDA_HI();
NutMicroDelay (1 * icb->delay_unit);
for (i = 0x80; i; i >>= 1) {
NutMicroDelay (2 * icb->delay_unit);
I2C_SCL_HI();
NutMicroDelay (2 * icb->delay_unit);
while(I2C_SCL_GET() == 0)
{
/* Clock stretching*/
NutMicroDelay (2 * icb->delay_unit);
}
if (I2C_SDA_GET()) {
rc |= i;
}
I2C_SCL_LO();
}
if (ack)
{
/* Master sets acknowledge */
I2C_SDA_LO();
}
NutMicroDelay (2 * icb->delay_unit);
I2C_SCL_HI();
NutMicroDelay (2 * icb->delay_unit);
I2C_SCL_LO();
NutMicroDelay (2 * icb->delay_unit);
return rc;
}
//------------------------------------------------------------------------------
//Initializes the ports for I2C
//------------------------------------------------------------------------------
void i2cSoftInit(void)
{
I2C_SDA_OUT();
I2C_SCL_OUT();
I2C_SDA_LO();
I2C_SCL_LO();
I2C_SDA_HI();
I2C_SCL_HI();
}
/*
* Rising edge on the data line while the clock line is high indicates
* a stop condition.
*
* Entry: SCL low, SDA any
* Exit: SCL high, SDA high
*/
static void TwStop(GPIO_TWICB* icb)
{
I2C_SDA_LO();
NutMicroDelay (icb->delay_unit);
I2C_SCL_HI();
NutMicroDelay (2 * icb->delay_unit);
I2C_SDA_HI();
NutMicroDelay (8 * icb->delay_unit);
}
/*
* Toggles out a single byte in master mode.
*
* Entry: SCL low, SDA any
* Exit: SCL low, SDA high
*
* Change SDA only when SCL is low!
* Sample SDA short before setting SCL low!
*/
static int TwPut(GPIO_TWICB* icb, uint8_t octet)
{
int i;
for (i = 0x80; i; i >>= 1) {
/* Set the data bit. */
if (octet & i) {
I2C_SDA_HI();
} else {
I2C_SDA_LO();
}
/* Wait for data to stabilize. */
NutMicroDelay (2 * icb->delay_unit);
/* Toggle the clock. */
I2C_SCL_HI();
NutMicroDelay (2 * icb->delay_unit);
while(I2C_SCL_GET() == 0)
{
/* Clock stretching*/
NutMicroDelay (2 * icb->delay_unit);
}
I2C_SCL_LO();
}
/* Release data line to receive the ACK bit. */
I2C_SDA_HI();
NutMicroDelay (2 * icb->delay_unit);
I2C_SCL_HI();
NutMicroDelay (2 * icb->delay_unit);
if (I2C_SDA_GET()) {
i = -1;
} else {
i = 0;
}
I2C_SCL_LO();
NutMicroDelay (2 * icb->delay_unit);
return i;
}
//-------------------------------------------
// Entry point for the application
//-------------------------------------------
void appMain(void)
{
#if 0 // no effect
UCTL0 = SWRST;
ME1 &= ~(URXE0 | UTXE0 | USPIE0);
UCTL0 &= ~SWRST;
UCTL1 = SWRST;
ME2 &= ~(URXE1 | UTXE1 | USPIE1);
UCTL1 &= ~SWRST;
#endif
#if 1
ADC12IE = 0;
ADC12IFG = 0;
ADC12CTL0 &= ~ENC;
ADC12CTL0 &= ~REFON;
ADC12CTL0 &= ~ADC12ON;
DMA0CTL = 0;
DMA1CTL = 0;
#endif
#if 0
pinAsData(1, 0);
pinAsData(1, 1);
pinAsData(1, 2);
pinAsData(1, 3);
pinAsData(1, 4);
pinAsData(1, 5);
pinAsData(1, 6);
pinAsData(1, 7); // radio data indicate
pinAsData(2, 0); // ADS interrupts (unused)
pinAsData(2, 1);
pinAsData(2, 2);
pinAsData(2, 3); // SHT SDA + I2C soft SDA
pinAsData(2, 4); // SHT SCL + I2C soft SCL
pinAsData(2, 5); // sensors enable
pinAsData(2, 6);
pinAsData(2, 7); // uart0 rx
pinAsData(3, 0); // SD card CS
pinAsData(3, 1);
pinAsData(3, 2);
pinAsData(3, 3);
pinAsData(3, 4); // uart0 hw tx
pinAsData(3, 5); // uart0 hw rx
pinAsData(3, 6); // uart1 hw tx
pinAsData(3, 7); // uart1 hw tx
pinAsData(4, 0); // radio data request
pinAsData(4, 1); // radio rts
pinAsData(4, 2); // radio config
pinAsData(4, 3); // radio trx disable
pinAsData(4, 4); // radio reset
pinAsData(4, 5); // radio sleep
// pinAsData(4, 6); // uart0 tx
// pinAsData(4, 7);
pinAsData(5, 0);
pinAsData(5, 1);
pinAsData(5, 2);
pinAsData(5, 3);
pinAsData(5, 4); // red LED
pinAsData(5, 5); // green LED
pinAsData(5, 6); // blue LED
pinAsData(5, 7);
pinAsData(6, 0);
pinAsData(6, 1);
pinAsData(6, 2);
pinAsData(6, 3);
pinAsData(6, 4);
pinAsData(6, 5);
pinAsData(6, 6);
pinAsData(6, 7);
#endif
pinAsInput(1, 0);
pinAsInput(1, 1);
pinAsInput(1, 2);
pinAsInput(1, 3);
pinAsInput(1, 4);
pinAsInput(1, 5);
pinAsInput(1, 6);
pinAsInput(1, 7); // radio data indicate
pinAsInput(2, 0); // ADS interrupts (unused)
pinAsInput(2, 1);
pinAsInput(2, 2);
pinAsInput(2, 3); // SHT SDA + I2C soft SDA
// pinAsInput(2, 4); // SHT SCL + I2C soft SCL
// pinAsInput(2, 5); // sensors enable
pinAsInput(2, 6);
pinAsInput(2, 7); // uart0 rx
pinAsInput(3, 0); // SD card CS
pinAsInput(3, 1);
pinAsInput(3, 2);
pinAsInput(3, 3);
pinAsInput(3, 4); // uart0 hw tx
pinAsInput(3, 5); // uart0 hw rx
pinAsInput(3, 6); // uart1 hw tx
pinAsInput(3, 7); // uart1 hw tx
pinAsInput(4, 0); // radio data request
pinAsInput(4, 1); // radio rts
pinAsInput(4, 2); // radio config
// pinAsInput(4, 3); // radio trx disable
pinAsInput(4, 4); // radio reset
// pinAsInput(4, 5); // radio sleep
pinAsInput(4, 6); // uart0 tx
pinAsInput(4, 7);
pinAsInput(5, 0);
pinAsInput(5, 1);
pinAsInput(5, 2);
pinAsInput(5, 3);
// pinAsInput(5, 4); // red LED
pinAsInput(5, 5); // green LED
pinAsInput(5, 6); // blue LED
pinAsInput(5, 7);
pinAsInput(6, 0);
pinAsInput(6, 1);
pinAsInput(6, 2);
pinAsInput(6, 3);
pinAsInput(6, 4);
pinAsInput(6, 5);
pinAsInput(6, 6);
pinAsInput(6, 7);
// -- required for better efficiency
// make sure I2C clock is high
I2C_SCL_HI();
// make sure sensors are disabled
pinClear(SM3_SENSORS_ENABLE_PORT, SM3_SENSORS_ENABLE_PIN);
// --
while (1) {
msleep(PAUSE); // sleep PAUSE seconds
// PRINTF("%lu: hello world\n", (uint32_t) getJiffies());
ledToggle();
}
}
