X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=bertos%2Fcfg%2Fmacros.h;h=0dad9d393effcb3f44abfa7aa85264c342a27206;hb=07f3470fff18b401711ba668af40e649347171e5;hp=abf2057d5308d43d56593d60d0d8ed2c642ac5c4;hpb=ebd302f4820855188df16ee8422a947751bf2c50;p=bertos.git

diff --git a/bertos/cfg/macros.h b/bertos/cfg/macros.h
index abf2057d..0dad9d39 100644
--- a/bertos/cfg/macros.h
+++ b/bertos/cfg/macros.h
@@ -154,6 +154,12 @@
 		(b) = tmp; \
 	} while (0)
 
+/**
+ * Reverse the bits contained in b (LSB becomes the MSB and so on).
+ * \note \a b is evaluated twice
+ */
+#define REVERSE(b) \
+	((uint8_t)((((b) * 0x0802UL & 0x22110UL) | ((b) * 0x8020UL & 0x88440UL)) * 0x10101UL >> 16))
 
 #ifndef BV
 	/** Convert a bit value to a binary flag. */
@@ -273,11 +279,11 @@
 
 	#define BIT_MASK_SINGLE__(use_bv, index, max, arg) \
 		((index < max) ? (PP_CAT(BIT_EXTRACT_FLAG_, use_bv) arg) : 0) \
-		/**/
+		/* */
 
 	#define BIT_MASK_IF_SINGLE__(use_bv, index, max, arg) \
 		(((index < max) && (BIT_EXTRACT_VALUE__ arg)) ? (PP_CAT(BIT_EXTRACT_FLAG_, use_bv) arg) : 0) \
-		/**/
+		/* */
 
 	#define BIT_ITER__2(macro, use_bv, max, a0,a1,a2,a3,a4,a5,a6,a7,a8,a9,a10,a11,a12,a13,a14,a15, ...) \
 		(macro(use_bv, 0, max, a0) | \
@@ -296,23 +302,23 @@
 		macro(use_bv, 13, max, a13) | \
 		macro(use_bv, 14, max, a14) | \
 		macro(use_bv, 15, max, a15)) \
-		/**/
+		/* */
 
 	#define BIT_ITER__(macro, use_bv, ...) \
 		BIT_ITER__2(macro, use_bv, PP_COUNT(__VA_ARGS__), __VA_ARGS__, (0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1),(0,1)) \
-		/**/
+		/* */
 
 	#define BIT_MASKS__(use_bv, ...) \
 		BIT_ITER__(BIT_MASK_SINGLE__, use_bv, __VA_ARGS__)
-		/**/
+		/* */
 
 	#define BIT_MASKS_CONDITIONAL__(use_bv, ...) \
 		BIT_ITER__(BIT_MASK_IF_SINGLE__, use_bv, __VA_ARGS__)
-		/**/
+		/* */
 
 	#define BIT_CHANGE__(reg, use_bv, ...) \
 		((reg) = ((reg) & ~BIT_MASKS__(use_bv, __VA_ARGS__)) | BIT_MASKS_CONDITIONAL__(use_bv, __VA_ARGS__)) \
-		/**/
+		/* */
 
 	#define BIT_CHANGE(reg, ...)        BIT_CHANGE__(reg, 0, __VA_ARGS__)
 	#define BIT_CHANGE_BV(reg, ...)     BIT_CHANGE__(reg, 1, __VA_ARGS__)