X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=altoslib%2FAltosHexfile.java;h=6a66a869454ef05fd77c3170cc4fa3d3d4b5cbd5;hb=master;hp=609d1bcb366f9f3ae747633f1f0a51e8894d04ad;hpb=3c48b0fd504ae97dfaca91d2064b5822ca6e1344;p=fw%2Faltos

diff --git a/altoslib/AltosHexfile.java b/altoslib/AltosHexfile.java
index 609d1bcb..71882600 100644
--- a/altoslib/AltosHexfile.java
+++ b/altoslib/AltosHexfile.java
@@ -16,7 +16,7 @@
  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  */
 
-package org.altusmetrum.altoslib_13;
+package org.altusmetrum.altoslib_14;
 
 import java.io.*;
 import java.util.LinkedList;
@@ -287,6 +287,8 @@ public class AltosHexfile {
 		return null;
 	}
 
+	private static final int look_around[] = { 0, -2, 2, -4, 4 };
+
 	private long find_usb_descriptors() {
 		AltosHexsym	usb_descriptors = lookup_symbol("ao_usb_descriptors");
 		long		a;
@@ -294,19 +296,22 @@ public class AltosHexfile {
 		if (usb_descriptors == null)
 			return -1;
 
-		try {
-			/* Walk the descriptors looking for the device */
-			a = usb_descriptors.address;
-			while (get_u8(a+1) != AO_USB_DESC_DEVICE) {
-				int delta = get_u8(a);
-				a += delta;
-				if (delta == 0 || a >= max_address)
-					return -1;
+		/* The address of this has moved depending on padding
+		 * in the linker script and romconfig symbols. Look
+		 * forward and backwards two and four bytes to see if
+		 * we can find it
+		 */
+		a = usb_descriptors.address;
+
+		for (int look : look_around) {
+			try {
+				if (get_u8(a + look) == 0x12 && get_u8(a + look + 1) == AO_USB_DESC_DEVICE)
+					return a;
+			} catch (ArrayIndexOutOfBoundsException ae) {
+				continue;
 			}
-			return a;
-		} catch (ArrayIndexOutOfBoundsException ae) {
-			return -1;
 		}
+		return -1;
 	}
 
 	public AltosUsbId find_usb_id() {