desktop: import updated DataFlash code

this fixes a logging bug

libraries/Desktop/support/DataFlash_APM1.cpp

@@ -1,3 +1,4 @@
+/// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
 /*
   hacked up DataFlash library for Desktop support
 */
@@ -118,7 +119,8 @@ void DataFlash_APM1::StartWrite(int16_t PageAdr)
   df_BufferIdx=4;
   df_PageAdr=PageAdr;
   df_Stop_Write=0;
-
+  WaitReady();
+      // We are starting a new page - write FileNumber and FilePage
 		BufferWrite(df_BufferNum,0,df_FileNumber>>8);   // High byte
 		BufferWrite(df_BufferNum,1,df_FileNumber&0xFF); // Low byte
 		BufferWrite(df_BufferNum,2,df_FilePage>>8);   // High byte
@@ -132,12 +134,12 @@ void DataFlash_APM1::FinishWrite(void)
 	df_PageAdr++;
 	if (OVERWRITE_DATA==1)
 	    {
-        if (df_PageAdr>=DF_LAST_PAGE)  // If we reach the end of the memory, start from the begining
+        if (df_PageAdr>DF_LAST_PAGE)  // If we reach the end of the memory, start from the begining
 		  df_PageAdr = 1;
 	    }
 	else
 	    {
-        if (df_PageAdr>=DF_LAST_PAGE)  // If we reach the end of the memory, stop here
+        if (df_PageAdr>DF_LAST_PAGE)  // If we reach the end of the memory, stop here
 		  df_Stop_Write=1;
 	    }
 
@@ -145,12 +147,6 @@ void DataFlash_APM1::FinishWrite(void)
         df_BufferNum=2;
 	else
         df_BufferNum=1;
-
-	BufferWrite(df_BufferNum,0,df_FileNumber>>8);   // High byte
-	BufferWrite(df_BufferNum,1,df_FileNumber&0xFF); // Low byte
-	df_FilePage++;
-	BufferWrite(df_BufferNum,2,df_FilePage>>8);   // High byte
-	BufferWrite(df_BufferNum,3,df_FilePage&0xFF); // Low byte
 }
 
 
@@ -162,17 +158,17 @@ void DataFlash_APM1::WriteByte(byte data)
     df_BufferIdx++;
     if (df_BufferIdx >= df_PageSize)  // End of buffer?
       {
-      df_BufferIdx=4;
+      df_BufferIdx=4;		//(4 bytes for FileNumber, FilePage)
 	  BufferToPage(df_BufferNum,df_PageAdr,0);  // Write Buffer to memory, NO WAIT
       df_PageAdr++;
 	  if (OVERWRITE_DATA==1)
 	    {
-        if (df_PageAdr>=DF_LAST_PAGE)  // If we reach the end of the memory, start from the begining
+        if (df_PageAdr>DF_LAST_PAGE)  // If we reach the end of the memory, start from the begining
 		  df_PageAdr = 1;
 	    }
       else
 	    {
-        if (df_PageAdr>=DF_LAST_PAGE)  // If we reach the end of the memory, stop here
+        if (df_PageAdr>DF_LAST_PAGE)  // If we reach the end of the memory, stop here
 		  df_Stop_Write=1;
 	    }
 
@@ -180,6 +176,12 @@ void DataFlash_APM1::WriteByte(byte data)
         df_BufferNum=2;
       else
         df_BufferNum=1;
+      // We are starting a new page - write FileNumber and FilePage
+		BufferWrite(df_BufferNum,0,df_FileNumber>>8);   // High byte
+		BufferWrite(df_BufferNum,1,df_FileNumber&0xFF); // Low byte
+		df_FilePage++;
+		BufferWrite(df_BufferNum,2,df_FilePage>>8);   // High byte
+		BufferWrite(df_BufferNum,3,df_FilePage&0xFF); // Low byte
       }
     }
 }
@@ -217,7 +219,16 @@ void DataFlash_APM1::StartRead(int16_t PageAdr)
   df_Read_PageAdr=PageAdr;
   WaitReady();
   PageToBuffer(df_Read_BufferNum,df_Read_PageAdr);  // Write Memory page to buffer
+//Serial.print(df_Read_PageAdr, DEC);	Serial.print("\t");
   df_Read_PageAdr++;
+
+      // We are starting a new page - read FileNumber and FilePage
+		df_FileNumber = BufferRead(df_Read_BufferNum,0);   // High byte
+//Serial.print(df_FileNumber, DEC);	Serial.print("\t");
+		df_FileNumber = (df_FileNumber<<8) | BufferRead(df_Read_BufferNum,1); // Low byte
+//Serial.println(df_FileNumber, DEC);	Serial.print("\t");
+		df_FilePage = BufferRead(df_Read_BufferNum,2);   // High byte
+		df_FilePage = (df_FilePage<<8) | BufferRead(df_Read_BufferNum,3); // Low byte
 }
 
 byte DataFlash_APM1::ReadByte()
@@ -229,14 +240,20 @@ byte DataFlash_APM1::ReadByte()
   df_Read_BufferIdx++;
   if (df_Read_BufferIdx >= df_PageSize)  // End of buffer?
     {
-    df_Read_BufferIdx=4;
+    df_Read_BufferIdx=4;		//(4 bytes for FileNumber, FilePage)
     PageToBuffer(df_Read_BufferNum,df_Read_PageAdr);  // Write memory page to Buffer
     df_Read_PageAdr++;
-    if (df_Read_PageAdr>=DF_LAST_PAGE)  // If we reach the end of the memory, start from the begining
+    if (df_Read_PageAdr>DF_LAST_PAGE)  // If we reach the end of the memory, start from the begining
       {
       df_Read_PageAdr = 0;
       df_Read_END = true;
       }
+
+      // We are starting a new page - read FileNumber and FilePage
+		df_FileNumber = BufferRead(df_Read_BufferNum,0);   // High byte
+		df_FileNumber = (df_FileNumber<<8) | BufferRead(df_Read_BufferNum,1); // Low byte
+		df_FilePage = BufferRead(df_Read_BufferNum,2);   // High byte
+		df_FilePage = (df_FilePage<<8) | BufferRead(df_Read_BufferNum,3); // Low byte
     }
   return result;
 }