X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/e0852408de92eada94b242cf84b007dc4f188467..a9abe1fdea5ccf67aaccab6fdde300d6fcf2d15a:/Projects/AVRISP-MKII/Lib/XPROG/XMEGANVM.c

diff --git a/Projects/AVRISP-MKII/Lib/XPROG/XMEGANVM.c b/Projects/AVRISP-MKII/Lib/XPROG/XMEGANVM.c
index e4f1186b0..820374fb9 100644
--- a/Projects/AVRISP-MKII/Lib/XPROG/XMEGANVM.c
+++ b/Projects/AVRISP-MKII/Lib/XPROG/XMEGANVM.c
@@ -1,13 +1,13 @@
 /*
              LUFA Library
-     Copyright (C) Dean Camera, 2011.
+     Copyright (C) Dean Camera, 2012.
 
   dean [at] fourwalledcubicle [dot] com
            www.lufa-lib.org
 */
 
 /*
-  Copyright 2011  Dean Camera (dean [at] fourwalledcubicle [dot] com)
+  Copyright 2012  Dean Camera (dean [at] fourwalledcubicle [dot] com)
 
   Permission to use, copy, modify, distribute, and sell this
   software and its documentation for any purpose is hereby granted
@@ -149,13 +149,18 @@ void XMEGANVM_DisablePDI(void)
 {
 	XMEGANVM_WaitWhileNVMBusBusy();
 
-	/* Clear the RESET key in the RESET PDI register to allow the XMEGA to run */
-	XPROGTarget_SendByte(PDI_CMD_STCS | PDI_RESET_REG);
-	XPROGTarget_SendByte(0x00);
+	/* 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);
 
-	/* Do it twice to make sure it takes effect (silicon bug?) */
-	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();
 }