/** Handler for the CMD_LEAVE_ISP command, which releases the target from programming mode. */
void ISPProtocol_LeaveISPMode(void)
{
struct
{
uint8_t PreDelayMS;
uint8_t PostDelayMS;
} Leave_ISP_Params;
Endpoint_Read_Stream_LE(&Leave_ISP_Params, sizeof(Leave_ISP_Params), NO_STREAM_CALLBACK);
Endpoint_ClearOUT();
Endpoint_SelectEndpoint(AVRISP_DATA_IN_EPNUM);
Endpoint_SetEndpointDirection(ENDPOINT_DIR_IN);
/* Perform pre-exit delay, release the target /RESET, disable the SPI bus and perform the post-exit delay */
ISPProtocol_DelayMS(Leave_ISP_Params.PreDelayMS);
ISPTarget_ChangeTargetResetLine(false);
ISPTarget_ShutDown();
ISPProtocol_DelayMS(Leave_ISP_Params.PostDelayMS);
/* Turn off the synchronous USART to terminate the recovery clock on XCK pin */
UBRR1 = (F_CPU / 500000UL);
UCSR1B = (1 << TXEN1);
UCSR1C = (1 << UMSEL10) | (1 << UPM11) | (1 << USBS1) | (1 << UCSZ11) | (1 << UCSZ10) | (1 << UCPOL1);
DDRD &= ~(1 << 5);
Endpoint_Write_Byte(CMD_LEAVE_PROGMODE_ISP);
Endpoint_Write_Byte(STATUS_CMD_OK);
Endpoint_ClearIN();
}
/** Handler for the CMD_LEAVE_ISP command, which releases the target from programming mode. */
void ISPProtocol_LeaveISPMode(void)
{
struct
{
uint8_t PreDelayMS;
uint8_t PostDelayMS;
} Leave_ISP_Params;
Endpoint_Read_Stream_LE(&Leave_ISP_Params, sizeof(Leave_ISP_Params), NULL);
Endpoint_ClearOUT();
Endpoint_SelectEndpoint(AVRISP_DATA_IN_EPADDR);
Endpoint_SetEndpointDirection(ENDPOINT_DIR_IN);
/* Perform pre-exit delay, release the target /RESET, disable the SPI bus and perform the post-exit delay */
ISPProtocol_DelayMS(Leave_ISP_Params.PreDelayMS);
ISPTarget_ChangeTargetResetLine(false);
ISPTarget_DisableTargetISP();
ISPProtocol_DelayMS(Leave_ISP_Params.PostDelayMS);
Endpoint_Write_8(CMD_LEAVE_PROGMODE_ISP);
Endpoint_Write_8(STATUS_CMD_OK);
Endpoint_ClearIN();
ISPActive = false;
}
/** Handler for the CMD_ENTER_PROGMODE_ISP command, which attempts to enter programming mode on
* the attached device, returning success or failure back to the host.
*/
void ISPProtocol_EnterISPMode(void)
{
struct
{
uint8_t TimeoutMS;
uint8_t PinStabDelayMS;
uint8_t ExecutionDelayMS;
uint8_t SynchLoops;
uint8_t ByteDelay;
uint8_t PollValue;
uint8_t PollIndex;
uint8_t EnterProgBytes[4];
} Enter_ISP_Params;
Endpoint_Read_Stream_LE(&Enter_ISP_Params, sizeof(Enter_ISP_Params), NULL);
Endpoint_ClearOUT();
Endpoint_SelectEndpoint(AVRISP_DATA_IN_EPADDR);
Endpoint_SetEndpointDirection(ENDPOINT_DIR_IN);
uint8_t ResponseStatus = STATUS_CMD_FAILED;
CurrentAddress = 0;
/* Perform execution delay, initialize SPI bus */
ISPProtocol_DelayMS(Enter_ISP_Params.ExecutionDelayMS);
ISPTarget_EnableTargetISP();
ISPTarget_ChangeTargetResetLine(true);
ISPProtocol_DelayMS(Enter_ISP_Params.PinStabDelayMS);
/* Continuously attempt to synchronize with the target until either the number of attempts specified
* by the host has exceeded, or the the device sends back the expected response values */
while (Enter_ISP_Params.SynchLoops-- && TimeoutTicksRemaining)
{
uint8_t ResponseBytes[4];
for (uint8_t RByte = 0; RByte < sizeof(ResponseBytes); RByte++)
{
ISPProtocol_DelayMS(Enter_ISP_Params.ByteDelay);
ResponseBytes[RByte] = ISPTarget_TransferByte(Enter_ISP_Params.EnterProgBytes[RByte]);
}
/* Check if polling disabled, or if the polled value matches the expected value */
if (!(Enter_ISP_Params.PollIndex) || (ResponseBytes[Enter_ISP_Params.PollIndex - 1] == Enter_ISP_Params.PollValue))
{
ResponseStatus = STATUS_CMD_OK;
break;
}
else
{
ISPTarget_ChangeTargetResetLine(false);
ISPProtocol_DelayMS(Enter_ISP_Params.PinStabDelayMS);
ISPTarget_ChangeTargetResetLine(true);
ISPProtocol_DelayMS(Enter_ISP_Params.PinStabDelayMS);
}
}
Endpoint_Write_8(CMD_ENTER_PROGMODE_ISP);
Endpoint_Write_8(ResponseStatus);
Endpoint_ClearIN();
}
/** Handler for the CMD_ENTER_PROGMODE_ISP command, which attempts to enter programming mode on
* the attached device, returning success or failure back to the host.
*/
void ISPProtocol_EnterISPMode(void)
{
struct
{
uint8_t TimeoutMS;
uint8_t PinStabDelayMS;
uint8_t ExecutionDelayMS;
uint8_t SynchLoops;
uint8_t ByteDelay;
uint8_t PollValue;
uint8_t PollIndex;
uint8_t EnterProgBytes[4];
} Enter_ISP_Params;
Endpoint_Read_Stream_LE(&Enter_ISP_Params, sizeof(Enter_ISP_Params), NO_STREAM_CALLBACK);
Endpoint_ClearOUT();
Endpoint_SelectEndpoint(AVRISP_DATA_IN_EPNUM);
Endpoint_SetEndpointDirection(ENDPOINT_DIR_IN);
uint8_t ResponseStatus = STATUS_CMD_FAILED;
CurrentAddress = 0;
/* Set up the synchronous USART to generate the .5MHz recovery clock on XCK pin */
UBRR1 = (F_CPU / 500000UL);
UCSR1B = (1 << TXEN1);
UCSR1C = (1 << UMSEL10) | (1 << UPM11) | (1 << USBS1) | (1 << UCSZ11) | (1 << UCSZ10) | (1 << UCPOL1);
DDRD |= (1 << 5);
/* Perform execution delay, initialize SPI bus */
ISPProtocol_DelayMS(Enter_ISP_Params.ExecutionDelayMS);
ISPTarget_Init();
/* Continuously attempt to synchronize with the target until either the number of attempts specified
* by the host has exceeded, or the the device sends back the expected response values */
while (Enter_ISP_Params.SynchLoops-- && (ResponseStatus == STATUS_CMD_FAILED) && TimeoutTicksRemaining)
{
uint8_t ResponseBytes[4];
ISPTarget_ChangeTargetResetLine(true);
ISPProtocol_DelayMS(Enter_ISP_Params.PinStabDelayMS);
for (uint8_t RByte = 0; RByte < sizeof(ResponseBytes); RByte++)
{
ISPProtocol_DelayMS(Enter_ISP_Params.ByteDelay);
ResponseBytes[RByte] = ISPTarget_TransferByte(Enter_ISP_Params.EnterProgBytes[RByte]);
}
/* Check if polling disabled, or if the polled value matches the expected value */
if (!(Enter_ISP_Params.PollIndex) || (ResponseBytes[Enter_ISP_Params.PollIndex - 1] == Enter_ISP_Params.PollValue))
{
ResponseStatus = STATUS_CMD_OK;
}
else
{
ISPTarget_ChangeTargetResetLine(false);
ISPProtocol_DelayMS(Enter_ISP_Params.PinStabDelayMS);
}
}
Endpoint_Write_Byte(CMD_ENTER_PROGMODE_ISP);
Endpoint_Write_Byte(ResponseStatus);
Endpoint_ClearIN();
}
