Added .5MHz recovery clock to the AVRISP programmer project when in ISP programming mode to correct mis-set fuses.

Fixed AVRISP project not extending the command delay after each successful page/word/byte program.

Projects/AVRISP-MKII/AVRISP.txt

@@ -110,6 +110,10 @@
  *   </tr>
  *  </table>
  *
+ *  In addition, the AVR's XCK pin will generate a .5MHz clock when SPI programming is used, to act as an external
+ *  device clock if the fuses have been mis-set. To use the recovery clock, connect XCK to the target AVR's XTAL1
+ *  pin, and set the ISP programming speed to 125KHz or below.
+ *
  *  <b><sup>1</sup></b> <i>Optional, see \ref SSec_Options section - for USB AVRs with ADC modules only</i> \n
  *  <b><sup>2</sup></b> <i>See AUX line related tokens in the \ref SSec_Options section</i>
  *

Projects/AVRISP-MKII/Lib/ISP/ISPProtocol.c

@@ -62,7 +62,14 @@ void ISPProtocol_EnterISPMode(void)
 	uint8_t ResponseStatus = STATUS_CMD_FAILED;
 	
 	CurrentAddress = 0;
+	
+	/* Set up the synchronous USART to generate 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);
 
+	/* Perform execution delay, initialize SPI bus */
 	ISPProtocol_DelayMS(Enter_ISP_Params.ExecutionDelayMS); 
 	SPI_Init(ISPTarget_GetSPIPrescalerMask() | SPI_SCK_LEAD_RISING | SPI_SAMPLE_LEADING | SPI_MODE_MASTER);
 
@@ -118,6 +125,12 @@ void ISPProtocol_LeaveISPMode(void)
 	SPI_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();

Projects/AVRISP-MKII/Lib/ISP/ISPTarget.c

@@ -139,6 +139,9 @@ uint8_t ISPTarget_WaitForProgComplete(const uint8_t ProgrammingMode, const uint1
 			ProgrammingStatus = ISPTarget_WaitWhileTargetBusy();
 			break;
 	}
+	
+	if (ProgrammingStatus == STATUS_CMD_OK)
+	  TimeoutMSRemaining = COMMAND_TIMEOUT_MS;
 
 	return ProgrammingStatus;
 }
@@ -159,10 +162,7 @@ uint8_t ISPTarget_WaitWhileTargetBusy(void)
 	}
 	while ((SPI_ReceiveByte() & 0x01) && TimeoutMSRemaining);
 
-	if (!(TimeoutMSRemaining))
-	  return STATUS_RDY_BSY_TOUT;
-	else
-	  return STATUS_CMD_OK;
+	return ((TimeoutMSRemaining) ? STATUS_CMD_OK : STATUS_RDY_BSY_TOUT);
 }
 
 /** Sends a low-level LOAD EXTENDED ADDRESS command to the target, for addressing of memory beyond the

Projects/AVRISP-MKII/Lib/XPROG/TINYNVM.c

@@ -82,9 +82,12 @@ bool TINYNVM_WaitWhileNVMBusBusy(void)
 		/* 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);
 		if (XPROGTarget_ReceiveByte() & TPI_STATUS_NVM)
-		  return true;
+		{
+			TimeoutMSRemaining = COMMAND_TIMEOUT_MS;
+			return true;
+		}
 	}
-	
+
 	return false;
 }
 
@@ -103,9 +106,12 @@ bool TINYNVM_WaitWhileNVMControllerBusy(void)
 
 		/* Check to see if the BUSY flag is still set */
 		if (!(XPROGTarget_ReceiveByte() & (1 << 7)))
-		  return true;
+		{
+			TimeoutMSRemaining = COMMAND_TIMEOUT_MS;
+			return true;
+		}
 	}
-	
+
 	return false;
 }
 
@@ -167,6 +173,10 @@ bool TINYNVM_WriteMemory(const uint16_t WriteAddress, uint8_t* WriteBuffer, uint
 	
 	while (WriteLength)
 	{
+		/* Wait until the NVM controller is no longer busy */
+		if (!(TINYNVM_WaitWhileNVMControllerBusy()))
+		  return false;
+
 		/* Write the low byte of data to the target */
 		XPROGTarget_SendByte(TPI_CMD_SST | TPI_POINTER_INDIRECT_PI);
 		XPROGTarget_SendByte(*(WriteBuffer++));
@@ -175,10 +185,6 @@ bool TINYNVM_WriteMemory(const uint16_t WriteAddress, uint8_t* WriteBuffer, uint
 		XPROGTarget_SendByte(TPI_CMD_SST | TPI_POINTER_INDIRECT_PI);
 		XPROGTarget_SendByte(*(WriteBuffer++));
 
-		/* Wait until the NVM controller is no longer busy */
-		if (!(TINYNVM_WaitWhileNVMControllerBusy()))
-		  return false;
-
 		/* Need to decrement the write length twice, since we read out a whole word */
 		WriteLength -= 2;
 	}

Projects/AVRISP-MKII/Lib/XPROG/XMEGANVM.c

@@ -77,7 +77,10 @@ bool XMEGANVM_WaitWhileNVMBusBusy(void)
 		/* 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);
 		if (XPROGTarget_ReceiveByte() & PDI_STATUS_NVM)
-		  return true;
+		{
+			TimeoutMSRemaining = COMMAND_TIMEOUT_MS;
+			return true;
+		}
 	}
 	
 	return false;
@@ -99,7 +102,10 @@ bool XMEGANVM_WaitWhileNVMControllerBusy(void)
 		
 		/* Check to see if the BUSY flag is still set */
 		if (!(XPROGTarget_ReceiveByte() & (1 << 7)))
-		  return true;
+		{
+			TimeoutMSRemaining = COMMAND_TIMEOUT_MS;
+			return true;
+		}
 	}
 	
 	return false;