diff --git a/src/target/samd.c b/src/target/samd.c
index f613408..6f3c574 100644
--- a/src/target/samd.c
+++ b/src/target/samd.c
@@ -715,11 +715,51 @@ static bool samd_set_flashlock(target *t, uint16_t value, const char **argv)
 	return true;
 }
 
+static bool parse_unsigned(const char *s, uint32_t *val) {
+	int l, st;
+	unsigned long num;
+	
+	l=strlen(s);
+	
+	if (l>2 && s[0]=='0' && (s[1]=='x' || s[1]=='X')) {
+		st=sscanf(s+2, "%lx", &num);
+	} else {
+		st=sscanf(s, "%lu", &num);
+	}
+	
+	if (st<1) {
+		return false;
+	}
+	
+	*val=(uint32_t)num;
+	return true;
+}
+
 static bool samd_cmd_lock_flash(target *t, int argc, const char **argv)
 {
+	unsigned long val;
+	
 	(void)argc;
 	(void)argv;
-	return samd_set_flashlock(t, 0x0000, NULL);
+	
+	if (argc>2) {
+		tc_printf(t, "usage: monitor lock_flash [number]\n");
+		return false;
+	} else if (argc==1) {
+		return samd_set_flashlock(t, 0x0000, NULL);
+	} else {
+		if (!parse_unsigned(argv[1], &val)) {
+			tc_printf(t, "number must be either decimal or 0x prefixed hexadecimal\n");
+			return false;
+		}
+		
+		if (val>0xffff) {
+			tc_printf(t, "number must be between 0 and 0xFFFF\n");
+			return false;
+		}
+		
+		return samd_set_flashlock(t, (uint16_t)val, NULL);
+	}
 }
 
 static bool samd_cmd_unlock_flash(target *t, int argc, const char **argv)
@@ -764,9 +804,30 @@ static bool samd_set_bootprot(target *t, uint16_t value, const char **argv)
 
 static bool samd_cmd_lock_bootprot(target *t, int argc, const char **argv)
 {
+	unsigned long val;
+	
 	(void)argc;
 	(void)argv;
-	return samd_set_bootprot(t, 0, NULL);
+	/* locks first 0x7 .. 0, 0x6 .. 512, 0x5 .. 1024, ..., 0x0 .. 32768 bytes of flash*/
+	
+	if (argc>2) {
+		tc_printf(t, "usage: monitor lock_bootprot [number]\n");
+		return false;
+	} else if (argc==1) {
+		return samd_set_bootprot(t, 0, NULL);
+	} else {
+		if (!parse_unsigned(argv[1], &val)) {
+			tc_printf(t, "number must be either decimal or 0x prefixed hexadecimal\n");
+			return false;
+		}
+		
+		if (val>7) {
+			tc_printf(t, "number must be between 0 and 7\n");
+			return false;
+		}
+		
+		return samd_set_bootprot(t, (uint16_t)val, NULL);
+	}
 }
 
 static bool samd_cmd_unlock_bootprot(target *t, int argc, const char **argv)