diff --git a/source/NTSC.cpp b/source/NTSC.cpp
index eda0cc56..65d0672c 100644
--- a/source/NTSC.cpp
+++ b/source/NTSC.cpp
@@ -1765,8 +1765,8 @@ void updateScreenSHR(long cycles6502)
 				uint8_t* pControl = MemGetAuxPtr(0x9D00 + g_nVideoClockVert);	// scan-line control byte
 				uint8_t c = pControl[0];
 
-				bool is640Mode = c & 0x80;
-				bool isColorFillMode = c & 0x20;
+				bool is640Mode = !!(c & 0x80);
+				bool isColorFillMode = !!(c & 0x20);
 				UINT paletteSelectCode = c & 0xf;
 				const UINT kColorsPerPalette = 16;
 				const UINT kColorSize = 2;
diff --git a/source/StdAfx.h b/source/StdAfx.h
index 17e39619..5db7e2bd 100644
--- a/source/StdAfx.h
+++ b/source/StdAfx.h
@@ -11,6 +11,7 @@
 #if _MSC_VER >= 1600	// <stdint.h> supported from VS2010 (cl.exe v16.00)
 #include <stdint.h> // cleanup WORD DWORD -> uint16_t uint32_t
 #else
+typedef INT8 int8_t;
 typedef UINT8 uint8_t;
 typedef UINT16 uint16_t;
 typedef UINT32 uint32_t;