diff --git a/global.h b/global.h
index ae9beb9..184ae25 100644
--- a/global.h
+++ b/global.h
@@ -90,5 +90,5 @@ int _write(int file, char *ptr, int len);
  *  @param[in] rjust justify representation with leading zeros
  *  @return string with binary representation of the number
  */
-char* b2s(uint32_t binary, uint8_t rjust);
+char* b2s(uint64_t binary, uint8_t rjust);