/** Reads memory from the target's memory spaces.
*
* \param[in] ReadAddress Start address to read from within the target's address space
* \param[out] ReadBuffer Buffer to store read data into
* \param[in] ReadSize Number of bytes to read
*
* \return Boolean true if the command sequence complete successfully
*/
bool XMEGANVM_ReadMemory(const uint32_t ReadAddress, uint8_t* ReadBuffer, uint16_t ReadSize)
{
/* Wait until the NVM controller is no longer busy */
if (!(XMEGANVM_WaitWhileNVMControllerBusy()))
return false;
/* Send the READNVM command to the NVM controller for reading of an arbitrary location */
XPROGTarget_SendByte(PDI_CMD_STS | (PDI_DATSIZE_4BYTES << 2));
XMEGANVM_SendNVMRegAddress(XMEGA_NVM_REG_CMD);
XPROGTarget_SendByte(XMEGA_NVM_CMD_READNVM);
/* Load the PDI pointer register with the start address we want to read from */
XPROGTarget_SendByte(PDI_CMD_ST | (PDI_POINTER_DIRECT << 2) | PDI_DATSIZE_4BYTES);
XMEGANVM_SendAddress(ReadAddress);
/* Send the REPEAT command with the specified number of bytes to read */
XPROGTarget_SendByte(PDI_CMD_REPEAT | PDI_DATSIZE_1BYTE);
XPROGTarget_SendByte(ReadSize - 1);
/* Send a LD command with indirect access and postincrement to read out the bytes */
XPROGTarget_SendByte(PDI_CMD_LD | (PDI_POINTER_INDIRECT_PI << 2) | PDI_DATSIZE_1BYTE);
while (ReadSize-- && TimeoutMSRemaining)
*(ReadBuffer++) = XPROGTarget_ReceiveByte();
return (TimeoutMSRemaining != 0);
}
/** Waits while the target's NVM controller is busy performing an operation, exiting if the
* timeout period expires.
*
* \return Boolean true if the NVM controller became ready within the timeout period, false otherwise
*/
bool XMEGANVM_WaitWhileNVMControllerBusy(void)
{
/* Poll the NVM STATUS register while the NVM controller is busy */
while (TimeoutMSRemaining)
{
/* Send a LDS command to read the NVM STATUS register to check the BUSY flag */
XPROGTarget_SendByte(PDI_CMD_LDS | (PDI_DATSIZE_4BYTES << 2));
XMEGANVM_SendNVMRegAddress(XMEGA_NVM_REG_STATUS);
uint8_t StatusRegister = XPROGTarget_ReceiveByte();
/* We might have timed out waiting for the status register read response, check here */
if (!(TimeoutMSRemaining))
return false;
/* Check to see if the BUSY flag is still set */
if (!(StatusRegister & (1 << 7)))
{
TimeoutMSRemaining = COMMAND_TIMEOUT_MS;
return true;
}
}
return false;
}
/** Waits while the target's NVM controller is busy performing an operation, exiting if the
* timeout period expires.
*
* \return Boolean \c true if the NVM controller became ready within the timeout period, \c false otherwise
*/
bool XMEGANVM_WaitWhileNVMControllerBusy(void)
{
/* Preload the pointer register with the NVM STATUS register address to check the BUSY flag */
XPROGTarget_SendByte(PDI_CMD_ST(PDI_POINTER_DIRECT, PDI_DATASIZE_4BYTES));
XMEGANVM_SendNVMRegAddress(XMEGA_NVM_REG_STATUS);
/* Poll the NVM STATUS register while the NVM controller is busy */
for (;;)
{
/* Fetch the current status value via the pointer register (without auto-increment afterwards) */
XPROGTarget_SendByte(PDI_CMD_LD(PDI_POINTER_INDIRECT, PDI_DATASIZE_1BYTE));
uint8_t StatusRegister = XPROGTarget_ReceiveByte();
/* We might have timed out waiting for the status register read response, check here */
if (TimeoutTicksRemaining == 0){
return false;
}
/* Check to see if the BUSY flag is still set */
if (!(StatusRegister & (1 << 7))) {
return true;
}
}
}
/** Removes access to the target's NVM controller and physically disables the target's physical TPI interface. */
void TINYNVM_DisableTPI(void)
{
TINYNVM_WaitWhileNVMBusBusy();
do
{
/* Clear the NVMEN bit in the TPI STATUS register to disable TPI mode */
XPROGTarget_SendByte(TPI_CMD_SSTCS | TPI_STATUS_REG);
XPROGTarget_SendByte(0x00);
/* Read back the STATUS register, check to see if it took effect */
XPROGTarget_SendByte(TPI_CMD_SLDCS | PDI_RESET_REG);
} while (XPROGTarget_ReceiveByte() != 0x00);
XPROGTarget_DisableTargetTPI();
}
/** Busy-waits while the NVM controller is busy performing a NVM operation, such as a FLASH page read.
*
* \return Boolean true if the NVM controller became ready within the timeout period, false otherwise
*/
bool TINYNVM_WaitWhileNVMBusBusy(void)
{
/* Poll the STATUS register to check to see if NVM access has been enabled */
for (;;)
{
/* Send the SLDCS command to read the TPI STATUS register to see the NVM bus is active */
XPROGTarget_SendByte(TPI_CMD_SLDCS | TPI_STATUS_REG);
uint8_t StatusRegister = XPROGTarget_ReceiveByte();
/* We might have timed out waiting for the status register read response, check here */
if (!(TimeoutTicksRemaining))
return false;
/* Check the status register read response to see if the NVM bus is enabled */
if (StatusRegister & TPI_STATUS_NVM)
return true;
}
}
/** Waits while the target's NVM controller is busy performing an operation, exiting if the
* timeout period expires.
*
* \return Boolean true if the NVM controller became ready within the timeout period, false otherwise
*/
bool TINYNVM_WaitWhileNVMControllerBusy(void)
{
/* Poll the STATUS register to check to see if NVM access has been enabled */
for (;;)
{
/* Send the SIN command to read the TPI STATUS register to see the NVM bus is busy */
TINYNVM_SendReadNVMRegister(XPROG_Param_NVMCSRRegAddr);
uint8_t StatusRegister = XPROGTarget_ReceiveByte();
/* We might have timed out waiting for the status register read response, check here */
if (!(TimeoutTicksRemaining))
return false;
/* Check to see if the BUSY flag is still set */
if (!(StatusRegister & (1 << 7)))
return true;
}
}
/** Removes access to the target's NVM controller and physically disables the target's physical PDI interface. */
void XMEGANVM_DisablePDI(void)
{
XMEGANVM_WaitWhileNVMBusBusy();
/* Clear the RESET key in the RESET PDI register to allow the XMEGA to run - must perform this until the
* change takes effect, as in some cases it takes multiple writes (silicon bug?).
*/
do
{
/* Clear reset register */
XPROGTarget_SendByte(PDI_CMD_STCS | PDI_RESET_REG);
XPROGTarget_SendByte(0x00);
/* Read back the reset register, check to see if it took effect */
XPROGTarget_SendByte(PDI_CMD_LDCS | PDI_RESET_REG);
} while (XPROGTarget_ReceiveByte() != 0x00);
XPROGTarget_DisableTargetPDI();
}
/** Retrieves the CRC value of the given memory space.
*
* \param[in] CRCCommand NVM CRC command to issue to the target
* \param[out] CRCDest CRC Destination when read from the target
*
* \return Boolean \c true if the command sequence complete successfully
*/
bool XMEGANVM_GetMemoryCRC(const uint8_t CRCCommand,
uint32_t* const CRCDest)
{
*CRCDest = 0;
/* Wait until the NVM controller is no longer busy */
if (!(XMEGANVM_WaitWhileNVMControllerBusy()))
return false;
/* Set the NVM command to the correct CRC read command */
XPROGTarget_SendByte(PDI_CMD_STS(PDI_DATASIZE_4BYTES, PDI_DATASIZE_1BYTE));
XMEGANVM_SendNVMRegAddress(XMEGA_NVM_REG_CMD);
XPROGTarget_SendByte(CRCCommand);
/* Set CMDEX bit in NVM CTRLA register to start the CRC generation */
XPROGTarget_SendByte(PDI_CMD_STS(PDI_DATASIZE_4BYTES, PDI_DATASIZE_1BYTE));
XMEGANVM_SendNVMRegAddress(XMEGA_NVM_REG_CTRLA);
XPROGTarget_SendByte(XMEGA_NVM_BIT_CTRLA_CMDEX);
/* Wait until the NVM bus is ready again */
if (!(XMEGANVM_WaitWhileNVMBusBusy()))
return false;
/* Wait until the NVM controller is no longer busy */
if (!(XMEGANVM_WaitWhileNVMControllerBusy()))
return false;
/* Load the PDI pointer register with the DAT0 register start address */
XPROGTarget_SendByte(PDI_CMD_ST(PDI_POINTER_DIRECT, PDI_DATASIZE_4BYTES));
XMEGANVM_SendNVMRegAddress(XMEGA_NVM_REG_DAT0);
/* Send the REPEAT command to grab the CRC bytes */
XPROGTarget_SendByte(PDI_CMD_REPEAT(PDI_DATASIZE_1BYTE));
XPROGTarget_SendByte(XMEGA_CRC_LENGTH_BYTES - 1);
/* Read in the CRC bytes from the target */
XPROGTarget_SendByte(PDI_CMD_LD(PDI_POINTER_INDIRECT_PI, PDI_DATASIZE_1BYTE));
for (uint8_t i = 0; i < XMEGA_CRC_LENGTH_BYTES; i++)
((uint8_t*)CRCDest)[i] = XPROGTarget_ReceiveByte();
return (TimeoutTicksRemaining > 0);
}
/** Reads memory from the target's memory spaces.
*
* \param[in] ReadAddress Start address to read from within the target's address space
* \param[out] ReadBuffer Buffer to store read data into
* \param[in] ReadSize Length of the data to read from the device
*
* \return Boolean true if the command sequence complete successfully
*/
bool TINYNVM_ReadMemory(const uint16_t ReadAddress,
uint8_t* ReadBuffer,
uint16_t ReadSize)
{
/* Wait until the NVM controller is no longer busy */
if (!(TINYNVM_WaitWhileNVMControllerBusy()))
return false;
/* Set the NVM control register to the NO OP command for memory reading */
TINYNVM_SendWriteNVMRegister(XPROG_Param_NVMCMDRegAddr);
XPROGTarget_SendByte(TINY_NVM_CMD_NOOP);
/* Send the address of the location to read from */
TINYNVM_SendPointerAddress(ReadAddress);
while (ReadSize-- && TimeoutTicksRemaining)
{
/* Read the byte of data from the target */
XPROGTarget_SendByte(TPI_CMD_SLD | TPI_POINTER_INDIRECT_PI);
*(ReadBuffer++) = XPROGTarget_ReceiveByte();
}
return (TimeoutTicksRemaining > 0);
}
/** Busy-waits while the NVM controller is busy performing a NVM operation, such as a FLASH page read or CRC
* calculation.
*
* \return Boolean true if the NVM controller became ready within the timeout period, false otherwise
*/
bool XMEGANVM_WaitWhileNVMBusBusy(void)
{
/* Poll the STATUS register to check to see if NVM access has been enabled */
while (TimeoutMSRemaining)
{
/* Send the LDCS command to read the PDI STATUS register to see the NVM bus is active */
XPROGTarget_SendByte(PDI_CMD_LDCS | PDI_STATUS_REG);
uint8_t StatusRegister = XPROGTarget_ReceiveByte();
/* We might have timed out waiting for the status register read response, check here */
if (!(TimeoutMSRemaining))
return false;
/* Check the status register read response to see if the NVM bus is enabled */
if (StatusRegister & PDI_STATUS_NVM)
{
TimeoutMSRemaining = COMMAND_TIMEOUT_MS;
return true;
}
}
return false;
}
