diff --git a/armsrc/hitagS.c b/armsrc/hitagS.c
index 684c83cbb..81ed771b4 100644
--- a/armsrc/hitagS.c
+++ b/armsrc/hitagS.c
@@ -454,7 +454,7 @@ static void hitagS_handle_reader_command(uint8_t *rx, const size_t rxlen,
                 //add crc8
                 *txlen = 40;
                 crc = CRC_PRESET;
-                calc_crc(&crc, tag.pages[1][2]), 8);
+                calc_crc(&crc, tag.pages[1][2], 8);
                 calc_crc(&crc, tag.pwdh0, 8);
                 calc_crc(&crc, tag.pwdl0, 8);
                 calc_crc(&crc, tag.pwdl1, 8);
diff --git a/armsrc/util.h b/armsrc/util.h
index 40a7c3026..06c4e024e 100644
--- a/armsrc/util.h
+++ b/armsrc/util.h
@@ -55,15 +55,15 @@
 #endif
 
 #ifndef REV16
-#define REV16(x)        (REV8(x) + (REV8 (x >> 8) << 8))
+#define REV16(x)        (REV8(x) + (REV8 ((x) >> 8) << 8))
 #endif
 
 #ifndef REV32
-#define REV32(x)        (REV16(x) + (REV16(x >> 16) << 16))
+#define REV32(x)        (REV16(x) + (REV16((x) >> 16) << 16))
 #endif
 
 #ifndef REV64
-#define REV64(x)        (REV32(x) + (REV32(x >> 32) << 32))
+#define REV64(x)        (REV32(x) + (REV32((x) >> 32) << 32))
 #endif
 
 #ifndef BIT32