diff --git a/armsrc/thinfilm.c b/armsrc/thinfilm.c
index 1e63571f7..c39316be5 100644
--- a/armsrc/thinfilm.c
+++ b/armsrc/thinfilm.c
@@ -158,7 +158,7 @@ void SimulateThinFilm(uint8_t *data, size_t len) {
 
     tosend_t *ts = get_tosend();
 
-    for (uint16_t i = 0; i < ts->max; i += 16) {
+    for (int i = 0; i < ts->max; i += 16) {
         Dbhexdump(16, ts->buf + i, false);
     }
     DbpString("------------------------------------------");