diff --git a/armsrc/iso15693.c b/armsrc/iso15693.c
index b5bda6a95..dfc3e6829 100644
--- a/armsrc/iso15693.c
+++ b/armsrc/iso15693.c
@@ -2496,8 +2496,8 @@ void SimTagIso15693(uint8_t *uid, uint8_t block_size) {
             case ISO15693_GET_RANDOM_NUMBER:
                 if (g_dbglevel >= DBG_DEBUG) Dbprintf("GetRandomNumber cmd");
                 recv[0] = ISO15_NOERROR;
-                recv[1] = (uint8_t)(reader_eof_time >> 24) ^ 0xFF; // poor random number
-                recv[2] = (uint8_t)(reader_eof_time >> 16) ^ 0xFF;
+                recv[1] = (uint8_t)(reader_eof_time) ^ 0xFF; // poor random number
+                recv[2] = (uint8_t)(reader_eof_time >> 8) ^ 0xFF;
                 recvLen = 3;
                 break;
             case ISO15693_ENABLE_PRIVACY: