diff --git a/README.md b/README.md
index 1119051..854937d 100644
--- a/README.md
+++ b/README.md
@@ -12,9 +12,6 @@ Open source tool and library for flashing Bouffalo RISC-V MCUs.
 - [ ] `bl61x` - BL616 / BL618
 - [ ] `bl808` - BL808
 
-# Supported Devices
-- [X] [Pinecil V2](https://wiki.pine64.org/wiki/Pinecil)
-
 # Supported OS
 - [x] Windows
 - [x] Linux
@@ -58,10 +55,3 @@ blisp --chip bl60x --reset -p /dev/ttyUSB0 name_of_firmware.bin
 # How to flash Pinecil V2
 
 Check out the [wiki page](https://github.com/pine64/blisp/wiki/Update-Pinecil-V2).
-
-# To Do
-
-- [ ] Another code style
-- [ ] Finalize API
-- [ ] SDIO and JTAG support
-- [ ] Add Apple support
diff --git a/include/blisp_util.h b/include/blisp_util.h
index 701041b..a17b071 100644
--- a/include/blisp_util.h
+++ b/include/blisp_util.h
@@ -2,12 +2,24 @@
 #ifndef _BLISP_UTIL_H
 #define _BLISP_UTIL_H
 
+#include <stdarg.h>
+#include <stdio.h>
 #ifdef WIN32
 #include <windows.h>
 #else
 #include <time.h>
 #endif
 
+static void blisp_dlog(const char* format, ...)
+{
+  fflush(stdout);
+  va_list args;
+  va_start(args, format);
+  vfprintf(stderr, format, args);
+  va_end(args);
+}
+
+
 static void sleep_ms(int milliseconds) {
 #ifdef WIN32
   Sleep(milliseconds);