uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity) {
if (quantity > BUFFER_LENGTH)
{
quantity = BUFFER_LENGTH;
}
// perform blocking read into buffer
int readed = 0;
TWI_StartRead(twi, address, 0, 0);
do {
// Stop condition must be set during the reception of last byte
if (readed + 1 == quantity)
{
TWI_SendSTOPCondition( twi);
}
TWI_WaitByteReceived(twi, RECV_TIMEOUT);
rxBuffer[readed++] = twi_read_byte(twi);
} while (readed < quantity);
TWI_WaitTransferComplete(twi, RECV_TIMEOUT);
// set rx buffer iterator vars
rxBufferIndex = 0;
rxBufferLength = readed;
return readed;
}
uint8_t TwoWire::requestFrom(uint8_t address, uint8_t quantity, uint32_t iaddress, uint8_t isize, uint8_t sendStop) {
if (quantity > BUFFER_LENGTH)
quantity = BUFFER_LENGTH;
// perform blocking read into buffer
int readed = 0;
TWI_StartRead(twi, address, iaddress, isize);
do {
// Stop condition must be set during the reception of last byte
if (readed + 1 == quantity)
TWI_SendSTOPCondition( twi);
if (TWI_WaitByteReceived(twi, RECV_TIMEOUT))
rxBuffer[readed++] = TWI_ReadByte(twi);
else
break;
} while (readed < quantity);
TWI_WaitTransferComplete(twi, RECV_TIMEOUT);
// set rx buffer iterator vars
rxBufferIndex = 0;
rxBufferLength = readed;
return readed;
}
/**
* \brief Asynchronously reads data from a slave on the TWI bus. An optional
* callback function is triggered when the transfer is complete.
* \param pTwid Pointer to a Twid instance.
* \param address TWI slave address.
* \param iaddress Optional slave internal address.
* \param isize Internal address size in bytes.
* \param pData Data buffer for storing received bytes.
* \param num Number of bytes to read.
* \param pAsync Asynchronous transfer descriptor.
* \return 0 if the transfer has been started; otherwise returns a TWI error code.
*/
uint8_t TWID_Read(
Twi *pTwi,
uint8_t address,
uint32_t iaddress,
uint8_t isize,
uint8_t *pData,
uint32_t num)
{
//Twi *pTwi;
uint32_t timeout;
assert( pTwi != NULL ) ;
assert( (address & 0x80) == 0 ) ;
assert( (iaddress & 0xFF000000) == 0 ) ;
assert( isize < 4 ) ;
/* Set STOP signal if only one byte is sent*/
if (num == 1) {
TWI_Stop(pTwi);
}
/* Synchronous transfer*/
/* Start read*/
TWI_StartRead(pTwi, address, iaddress, isize);
/* Read all bytes, setting STOP before the last byte*/
while (num > 0) {
/* Last byte ?*/
if (num == 1) {
TWI_Stop(pTwi);
}
/* Wait for byte then read and store it*/
timeout = 0;
while( !TWI_ByteReceived(pTwi) && (++timeout<TWITIMEOUTMAX) );
if (timeout == TWITIMEOUTMAX) {
TRACE_ERROR("TWID Timeout BR\n\r");
}
*pData++ = TWI_ReadByte(pTwi);
num--;
}
/* Wait for transfer to be complete */
timeout = 0;
while( !TWI_TransferComplete(pTwi) && (++timeout<TWITIMEOUTMAX) );
if (timeout == TWITIMEOUTMAX) {
TRACE_ERROR("TWID Timeout TC\n\r");
}
return 0;
}
// i2c_eeprom_master_read/write are based on twid.c from atmels at91lib and
// adapted for better handling when there is no eeprom present.
// This handling is needed for the bricklet initialization
bool i2c_eeprom_master_read(Twi *twi,
const uint16_t internal_address,
char *data,
const uint16_t length) {
uint32_t timeout;
mutex_take(mutex_twi_bricklet, MUTEX_BLOCKING);
// Start read
TWI_StartRead(twi,
bricklet_eeprom_address,
internal_address,
I2C_EEPROM_INTERNAL_ADDRESS_BYTES);
for(uint16_t i = 0; i < length; i++) {
// If last Byte -> send STOP
if(i == length-1) {
TWI_Stop(twi);
}
uint32_t timeout = 0;
// Wait until byte is received, otherwise return false
while(!TWI_ByteReceived(twi) && (++timeout < I2C_EEPROM_TIMEOUT));
if(timeout == I2C_EEPROM_TIMEOUT) {
logieew("read timeout (nothing received)\n\r");
mutex_give(mutex_twi_bricklet);
return false;
}
data[i] = TWI_ReadByte(twi);
}
timeout = 0;
// Wait for transfer to be complete
while(!TWI_TransferComplete(twi) && (++timeout < I2C_EEPROM_TIMEOUT));
if (timeout == I2C_EEPROM_TIMEOUT) {
logieew("read timeout (transfer incomplete)\n\r");
mutex_give(mutex_twi_bricklet);
return false;
}
mutex_give(mutex_twi_bricklet);
return true;
}
unsigned char ReadAccelData(unsigned int iaddress, char *bytes, unsigned int num)
{
unsigned int timeout;
// wait for TWI bus to be ready
while(!(TWI_TransferComplete(AT91C_BASE_TWI))) nop();
// Start Reading
TWI_StartRead(AT91C_BASE_TWI, ACCELADDR,iaddress,1);
while (num > 0) {
// Last byte
if(num == 1) TWI_Stop(AT91C_BASE_TWI);
// wait for byte then read and store it
timeout = 0;
while(!TWI_ByteReceived(AT91C_BASE_TWI) && (++timeout<TWITIMEOUTMAX)) nop();
if(timeout == TWITIMEOUTMAX) return 2;
*bytes++ = TWI_ReadByte(AT91C_BASE_TWI);
num--;
}
return 0;
}
/**
* \brief Asynchronously reads data from a slave on the TWI bus. An optional
* callback function is triggered when the transfer is complete.
* \param pTwid Pointer to a Twid instance.
* \param address TWI slave address.
* \param iaddress Optional slave internal address.
* \param isize Internal address size in bytes.
* \param pData Data buffer for storing received bytes.
* \param num Number of bytes to read.
* \param pAsync Asynchronous transfer descriptor.
* \return 0 if the transfer has been started; otherwise returns a TWI error code.
*/
uint8_t TWID_Read(
Twid *pTwid,
uint8_t address,
uint32_t iaddress,
uint8_t isize,
uint8_t *pData,
uint32_t num,
Async *pAsync)
{
Twi *pTwi;
AsyncTwi *pTransfer;
uint32_t timeout;
assert( pTwid != NULL ) ;
pTwi = pTwid->pTwi;
pTransfer = (AsyncTwi *) pTwid->pTransfer;
assert( (address & 0x80) == 0 ) ;
assert( (iaddress & 0xFF000000) == 0 ) ;
assert( isize < 4 ) ;
/* Check that no transfer is already pending*/
if (pTransfer) {
TRACE_ERROR("TWID_Read: A transfer is already pending\n\r");
return TWID_ERROR_BUSY;
}
/* Set STOP signal if only one byte is sent*/
if (num == 1) {
TWI_Stop(pTwi);
}
/* Asynchronous transfer*/
if (pAsync) {
/* Update the transfer descriptor */
pTwid->pTransfer = pAsync;
pTransfer = (AsyncTwi *) pAsync;
pTransfer->status = ASYNC_STATUS_PENDING;
pTransfer->pData = pData;
pTransfer->num = num;
pTransfer->transferred = 0;
/* Enable read interrupt and start the transfer */
TWI_EnableIt(pTwi, TWI_IER_RXRDY);
TWI_StartRead(pTwi, address, iaddress, isize);
}
/* Synchronous transfer*/
else {
/* Start read*/
TWI_StartRead(pTwi, address, iaddress, isize);
/* Read all bytes, setting STOP before the last byte*/
while (num > 0) {
/* Last byte ?*/
if (num == 1) {
TWI_Stop(pTwi);
}
/* Wait for byte then read and store it*/
timeout = 0;
while( !TWI_ByteReceived(pTwi) && (++timeout<TWITIMEOUTMAX) ) {
if(pTwi->TWI_SR & TWI_SR_NACK) {
return 0;
}
}
if (timeout == TWITIMEOUTMAX) {
TRACE_ERROR("TWID Timeout BR\n\r");
*pData++ = 0;
} else {
*pData++ = TWI_ReadByte(pTwi);
}
num--;
}
/* Wait for transfer to be complete */
timeout = 0;
while( !TWI_TransferComplete(pTwi) && (++timeout<TWITIMEOUTMAX) );
if (timeout == TWITIMEOUTMAX) {
TRACE_ERROR("TWID Timeout TC\n\r");
}
}
pTwi->TWI_SR;
pTwi->TWI_RHR;
return 0;
}
/**
* \brief Asynchronously reads data from a slave on the TWI bus. An optional
* callback function is triggered when the transfer is complete.
* \param pTwid Pointer to a Twid instance.
* \param address TWI slave address.
* \param iaddress Optional slave internal address.
* \param isize Internal address size in bytes.
* \param pData Data buffer for storing received bytes.
* \param num Number of bytes to read.
* \param pAsync Asynchronous transfer descriptor.
* \return 0 if the transfer has been started; otherwise returns a TWI error code.
*/
uint8_t TWID_Read(
Twid *pTwid,
uint8_t address,
uint32_t iaddress,
uint8_t isize,
uint8_t *pData,
uint32_t num,
Async *pAsync)
{
Twi *pTwi;
AsyncTwi *pTransfer;
uint32_t timeout = 0;
uint32_t i = 0;
uint32_t status;
assert( pTwid != NULL ) ;
pTwi = pTwid->pTwi;
pTransfer = (AsyncTwi *) pTwid->pTransfer;
assert( (address & 0x80) == 0 ) ;
assert( (iaddress & 0xFF000000) == 0 ) ;
assert( isize < 4 ) ;
/* Check that no transfer is already pending*/
if (pTransfer) {
TRACE_ERROR("TWID_Read: A transfer is already pending\n\r");
return TWID_ERROR_BUSY;
}
/* Asynchronous transfer*/
if (pAsync) {
/* Update the transfer descriptor */
pTwid->pTransfer = pAsync;
pTransfer = (AsyncTwi *) pAsync;
pTransfer->status = ASYNC_STATUS_PENDING;
pTransfer->pData = pData;
pTransfer->num = num;
pTransfer->transferred = 0;
/* Enable read interrupt and start the transfer */
TWI_EnableIt(pTwi, TWI_IER_RXRDY);
TWI_StartRead(pTwi, address, iaddress, isize);
}
/* Synchronous transfer*/
else {
/* Start read*/
TWI_StartRead(pTwi, address, iaddress, isize);
if (num != 1)
{
status = TWI_GetStatus(pTwi);
if(status & TWI_SR_NACK)
TRACE_ERROR("TWID NACK error\n\r");
timeout = 0;
while( ! (status & TWI_SR_RXRDY) && (++timeout<TWITIMEOUTMAX))
{
status = TWI_GetStatus(pTwi);
//TRACE_ERROR("TWID status %x\n\r",TWI_GetStatus(pTwi));
}
pData[0] = TWI_ReadByte(pTwi);
for( i = 1; i < num - 1; i++)
{
status = TWI_GetStatus(pTwi);
if(status & TWI_SR_NACK)
TRACE_ERROR("TWID NACK error\n\r");
timeout = 0;
while( ! (status & TWI_SR_RXRDY) && (++timeout<TWITIMEOUTMAX))
{
status = TWI_GetStatus(pTwi);
//TRACE_ERROR("TWID status %x\n\r",TWI_GetStatus(pTwi));
}
pData[i] = TWI_ReadByte(pTwi);
}
}
TWI_Stop(pTwi);
status = TWI_GetStatus(pTwi);
if(status & TWI_SR_NACK)
TRACE_ERROR("TWID NACK error\n\r");
timeout = 0;
while( ! (status & TWI_SR_RXRDY) && (++timeout<TWITIMEOUTMAX))
{
status = TWI_GetStatus(pTwi);
//TRACE_ERROR("TWID status %x\n\r",TWI_GetStatus(pTwi));
}
pData[i] = TWI_ReadByte(pTwi);
timeout = 0;
status = TWI_GetStatus(pTwi);
while( !(status & TWI_SR_TXCOMP) && (++timeout<TWITIMEOUTMAX))
{
status = TWI_GetStatus(pTwi);
//TRACE_ERROR("TWID status %x\n\r",TWI_GetStatus(pTwi));
}
#if 0
/* Read all bytes, setting STOP before the last byte*/
while (num > 0) {
/* Last byte ?*/
if (num == 1) {
TWI_Stop(pTwi);
}
/* Wait for byte then read and store it*/
timeout = 0;
while( !TWI_ByteReceived(pTwi) && (++timeout<TWITIMEOUTMAX) );
if (timeout == TWITIMEOUTMAX) {
TRACE_ERROR("TWID Timeout BR\n\r");
}
*pData++ = TWI_ReadByte(pTwi);
num--;
}
/* Wait for transfer to be complete */
timeout = 0;
while( !TWI_TransferComplete(pTwi) && (++timeout<TWITIMEOUTMAX) );
if (timeout == TWITIMEOUTMAX) {
TRACE_ERROR("TWID Timeout TC\n\r");
}
#endif
}
return 0;
}
//-----------------------------------------------------------------------------
/// Asynchronously reads data from a slave on the TWI bus. An optional
/// callback function is triggered when the transfer is complete.
/// Returns 0 if the transfer has been started; otherwise returns a TWI error
/// code.
/// \param pTwid Pointer to a Twid instance.
/// \param address TWI slave address.
/// \param iaddress Optional slave internal address.
/// \param isize Internal address size in bytes.
/// \param pData Data buffer for storing received bytes.
/// \param num Number of bytes to read.
/// \param pAsync Asynchronous transfer descriptor.
//-----------------------------------------------------------------------------
unsigned char TWID_Read(
Twid *pTwid,
unsigned char address,
unsigned int iaddress,
unsigned char isize,
unsigned char *pData,
unsigned int num,
Async *pAsync)
{
AT91S_TWI *pTwi = pTwid->pTwi;
AsyncTwi *pTransfer = (AsyncTwi *) pTwid->pTransfer;
unsigned int timeout;
//TRACE_DEBUG("TWID_Read()\n\r");
SANITY_CHECK(pTwid);
SANITY_CHECK((address & 0x80) == 0);
SANITY_CHECK((iaddress & 0xFF000000) == 0);
SANITY_CHECK(isize < 4);
// Check that no transfer is already pending
if (pTransfer) {
TRACE_ERROR("TWID_Read: A transfer is already pending\n\r");
return TWID_ERROR_BUSY;
}
// Set STOP signal if only one byte is sent
if (num == 1) {
TWI_Stop(pTwi);
}
// Asynchronous transfer
if (pAsync) {
// Update the transfer descriptor
pTwid->pTransfer = pAsync;
pTransfer = (AsyncTwi *) pAsync;
pTransfer->status = ASYNC_STATUS_PENDING;
pTransfer->pData = pData;
pTransfer->num = num;
pTransfer->transferred = 0;
// Enable read interrupt and start the transfer
TWI_EnableIt(pTwi, AT91C_TWI_RXRDY);
TWI_StartRead(pTwi, address, iaddress, isize);
}
// Synchronous transfer
else {
// Start read
TWI_StartRead(pTwi, address, iaddress, isize);
// Read all bytes, setting STOP before the last byte
while (num > 0) {
// Last byte
if (num == 1) {
TWI_Stop(pTwi);
}
// Wait for byte then read and store it
timeout = 0;
while( !TWI_ByteReceived(pTwi) && (++timeout<TWITIMEOUTMAX) );
if (timeout == TWITIMEOUTMAX) {
TRACE_ERROR("TWID Timeout BR\n\r");
return TWID_ERROR_TIMEOUT;
}
*pData++ = TWI_ReadByte(pTwi);
num--;
}
// Wait for transfer to be complete
timeout = 0;
while( !TWI_TransferComplete(pTwi) && (++timeout<TWITIMEOUTMAX) );
if (timeout == TWITIMEOUTMAX) {
TRACE_ERROR("TWID Timeout TC\n\r");
return TWID_ERROR_TIMEOUT;
}
}
return 0;
}
