Add macros to handle endianess issues.

git-svn-id: https://src.develer.com/svnoss/bertos/trunk@60 38d2e660-2303-0410-9eaa-f027e97ec537

diff --git a/cpu.h b/cpu.h
index 335876130765ffd001011786086c1da0aef8101b..09240a0a68a7faeffe3bcd9f518847efa3fe2bee 100755 (executable)
--- a/cpu.h
+++ b/cpu.h
@@ -15,6 +15,9 @@
 
 /*
  * $Log$
+ * Revision 1.4  2004/07/20 16:06:04  bernie
+ * Add macros to handle endianess issues.
+ *
  * Revision 1.3  2004/07/18 21:49:51  bernie
  * Fixes for GCC 3.5.
  *
@@ -33,6 +36,11 @@
 //! Initialization value for registers in stack frame
 #define CPU_REG_INIT_VALUE(reg)     0
 
+// Macros for determining CPU endianness
+#define CPU_BIG_ENDIAN    0x1234
+#define CPU_LITTLE_ENDIAN 0x3412
+
+
 #if defined(__IAR_SYSTEMS_ICC) || defined(__IAR_SYSTEMS_ICC__)  /* 80C196 */
 
        #define DISABLE_INTS            disable_interrupt()
@@ -46,6 +54,7 @@
        #define CPU_REGS_CNT            16
        #define CPU_STACK_GROWS_UPWARD  0
        #define CPU_SP_ON_EMPTY_SLOT    0
+       #define CPU_BYTE_ORDER          CPU_LITTLE_ENDIAN
 
 #elif defined(__i386__) || defined(_MSC_VER) /* x86 */
 
@@ -60,6 +69,7 @@
        #define CPU_REGS_CNT            7
        #define CPU_STACK_GROWS_UPWARD  0
        #define CPU_SP_ON_EMPTY_SLOT    0
+       #define CPU_BYTE_ORDER          CPU_LITTLE_ENDIAN
 
 #elif defined(__m56800E__) || defined(__m56800__) /* DSP56K */
 
@@ -80,6 +90,7 @@
        #define CPU_SAVED_REGS_CNT      28
        #define CPU_STACK_GROWS_UPWARD  1
        #define CPU_SP_ON_EMPTY_SLOT    0
+       #define CPU_BYTE_ORDER          CPU_BIG_ENDIAN
 
        #undef CPU_REG_INIT_VALUE
        INLINE uint16_t CPU_REG_INIT_VALUE(int reg)
@@ -125,7 +136,7 @@
        #define CPU_SAVED_REGS_CNT      18
        #define CPU_STACK_GROWS_UPWARD  0
        #define CPU_SP_ON_EMPTY_SLOT    1
-
+       #define CPU_BYTE_ORDER          CPU_LITTLE_ENDIAN
 #else
        #error Unknown CPU
 #endif
@@ -202,4 +213,23 @@
                CPU_PUSH_WORD((sp), (func))
 #endif
 
+
+INLINE uint16_t htobe16(uint16_t n);
+INLINE uint16_t htobe16(uint16_t n)
+{
+       if (CPU_BYTE_ORDER == CPU_LITTLE_ENDIAN)
+               n = n << 8 | n >> 8;
+
+       return n;
+}
+
+INLINE uint16_t htole16(uint16_t n);
+INLINE uint16_t htole16(uint16_t n)
+{
+       if (CPU_BYTE_ORDER == CPU_BIG_ENDIAN)
+               n = n << 8 | n >> 8;
+
+       return n;
+}
+
 #endif /* CPU_H */