Dangerous Prototypes Open Source Hardware

diff -uN b/I2C.c a/I2C.c
--- b/I2C.c	2011-02-07 14:34:15.000000000 +0200
+++ a/I2C.c	2011-02-07 14:34:01.000000000 +0200
@@ -717,14 +717,22 @@
 	{
 		if(!IFS1bits.CNIF){//check change notice interrupt
 			//user IO service
+#if !defined (BUSPIRATEV4)
 			if(U1STAbits.UTXBF == 0){//check first, don;t waste time jumping to function
+#endif
 				UARTbufService();
+#if defined (BUSPIRATEV4)
+				if( UART1RXRdy() >=1 ){
+#else
 				if(U1STAbits.URXDA == 1){//any key pressed, exit
 					dat=U1RXREG;
+#endif
 					break;
 				}		
 				continue; 
+#if !defined (BUSPIRATEV4)
 			}
+#endif
 		}
 
 		IFS1bits.CNIF=0;//clear interrupt flag
diff -uN b/baseIO.c a/baseIO.c
--- b/baseIO.c	2011-02-07 14:34:11.000000000 +0200
+++ a/baseIO.c	2011-02-07 14:34:00.000000000 +0200
@@ -469,10 +469,17 @@
 	i=readpointer+1;
 	if(i==TERMINAL_BUFFER) i=0; //check for wrap
 	if(i==writepointer) return; //buffer empty, 
-
+#if !defined (BUSPIRATEV4)
 	if(U1STAbits.UTXBF == 0){//free slot, move a byte to UART
+#else
+	if(USBUSARTIsTxTrfReady()){	
+#endif
 		readpointer=i;
+#if !defined (BUSPIRATEV4)
 		U1TXREG=bpConfig.terminalInput[readpointer];
+#else
+		UART1TX(bpConfig.terminalInput[readpointer]);
+#endif
 	}
 }
 
@@ -483,10 +490,17 @@
 		i=readpointer+1;
 		if(i==TERMINAL_BUFFER) i=0; //check for wrap
 		if(i==writepointer) return; //buffer empty, 
-	
+#if defined (BUSPIRATEV4)	
+		if(USBUSARTIsTxTrfReady()){	
+#else
 		if(U1STAbits.UTXBF == 0){//free slot, move a byte to UART
+#endif
 			readpointer=i;
+#if !defined (BUSPIRATEV4)
 			U1TXREG=bpConfig.terminalInput[readpointer];
+#else
+			UART1TX(bpConfig.terminalInput[readpointer]);
+#endif
 		}
 	}
 }

I you need these features now, I highly recommend a Bus Pirate v3. If you got the v4 instead by mistake, please let me know, I will swap it with a v3 for you.