Example for FS-BB48 to compute CRC32.

author: NIIBE Yutaka <gniibe@fsij.org> 2016-04-19 15:58:26 +0900
committer: NIIBE Yutaka <gniibe@fsij.org> 2016-04-19 15:58:26 +0900
commit: 7c2cdaa6e40999d1194cc7188742f0c21acfa0da (patch)
tree: 0b70c3be9d96745a4b4b3571e813cf807f81a23b /example-fs-bb48
parent: 0bbb43dd3a943285ffb5462db468f7af29c4bbfb (diff)
5 files changed, 129 insertions, 4 deletions
diff --git a/example-fs-bb48/Makefile b/example-fs-bb48/Makefile
index b60cfde..cc93c9b 100644
--- a/example-fs-bb48/Makefile
+++ b/example-fs-bb48/Makefile
@@ -6,7 +6,7 @@ PROJECT = sample
 
 CHOPSTX = ..
 LDSCRIPT= sample.ld
-CSRC = sample.c reset.c usb_kl27z.c usb-cdc.c
+CSRC = sample.c reset.c usb_kl27z.c usb-cdc.c crc32.c
 
 ###################################
 CROSS = arm-none-eabi-
diff --git a/example-fs-bb48/crc32.c b/example-fs-bb48/crc32.c
new file mode 100644
index 0000000..7475554
--- /dev/null
+++ b/example-fs-bb48/crc32.c
@@ -0,0 +1,81 @@
+/*
+ * CRC32.c - CRC32 calculation routines.
+ */
+
+/*
+ * Table of CRC32, generated by gen_crc_table.py
+ */
+static unsigned int crc32_table[256] = {
+  0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 
+  0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 
+  0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, 
+  0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, 
+  0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 
+  0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 
+  0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, 
+  0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, 
+  0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 
+  0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 
+  0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, 
+  0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, 
+  0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 
+  0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 
+  0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, 
+  0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, 
+  0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 
+  0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 
+  0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, 
+  0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, 
+  0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 
+  0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 
+  0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, 
+  0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, 
+  0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 
+  0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 
+  0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, 
+  0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, 
+  0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 
+  0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 
+  0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, 
+  0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, 
+  0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 
+  0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 
+  0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, 
+  0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, 
+  0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 
+  0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 
+  0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, 
+  0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, 
+  0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 
+  0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 
+  0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
+};
+
+static unsigned int crc_reg;
+
+void
+crc32_init (void)
+{
+  crc_reg = 0xffffffff;
+}
+
+unsigned int
+crc32_value (void)
+{
+  return crc_reg;
+}
+
+void
+crc32_u8 (unsigned char bits_eight)
+{
+  crc_reg = crc32_table[(crc_reg & 0xff) ^ bits_eight] ^ (crc_reg >> 8);
+}
+
+void
+crc32_u32 (unsigned int u)
+{
+  crc32_u8 (u & 0xff);
+  crc32_u8 ((u >> 8)& 0xff);
+  crc32_u8 ((u >> 16)& 0xff);
+  crc32_u8 ((u >> 24)& 0xff);
+}
diff --git a/example-fs-bb48/crc32.h b/example-fs-bb48/crc32.h
new file mode 100644
index 0000000..c31ba0f
--- /dev/null
+++ b/example-fs-bb48/crc32.h
@@ -0,0 +1,5 @@
+void crc32_init (void);
+void crc32_u8 (unsigned char);
+void crc32_u32 (unsigned int);
+
+unsigned int crc32_value (void);
diff --git a/example-fs-bb48/gen_crc_table.py b/example-fs-bb48/gen_crc_table.py
new file mode 100644
index 0000000..908531a
--- /dev/null
+++ b/example-fs-bb48/gen_crc_table.py
@@ -0,0 +1,22 @@
+# 
+# Polynomial for CRC32:
+#    x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 + x7 + x5 + x4 + x2 + x + 1
+#
+# When it is represented in binary, it's:
+#    0x04C11DB7
+#    =
+#    0000 0100 1100 0001 0001 1101 1011 0111
+# 
+# When we put in reverse bit-order, it's
+#    0xedb88320
+
+for i in range(0,256):
+    c = i
+    for j in range(0,8):
+        if (c&1):
+            c = 0xEDB88320 ^ (c >> 1)
+        else:
+            c = c >> 1
+    print("0x%08x," % c),
+    if (i % 6) == 5:
+        print("")
diff --git a/example-fs-bb48/sample.c b/example-fs-bb48/sample.c
index aa69144..f1c19e5 100644
--- a/example-fs-bb48/sample.c
+++ b/example-fs-bb48/sample.c
@@ -7,6 +7,8 @@
 #include "stream.h"
 #include "board.h"
 
+#include "crc32.h"
+
 struct GPIO {
   volatile uint32_t PDOR; /* Port Data Output Register    */
   volatile uint32_t PSOR; /* Port Set Output Register     */
@@ -216,12 +218,27 @@ main (int argc, const char *argv[])
 
 	  if (size >= 0)
 	    {
+	      int i;
+	      unsigned int value;
+
+	      crc32_init ();
 	      s[0] = hexchar (size >> 4);
 	      s[1] = hexchar (size & 0x0f);
 
-	      s[size + 4] = '\r';
-	      s[size + 5] = '\n';
-	      if (stream_send (st, s, size + 6) < 0)
+	      for (i = 0; i < size; i++)
+		crc32_u8 (s + 4 + i);
+	      value = crc32_value () ^ 0xffffffff;
+	      s[4] = hexchar (value >> 28);
+	      s[5] = hexchar (value >> 24);
+	      s[6] = hexchar (value >> 20);
+	      s[7] = hexchar (value >> 16);
+	      s[8] = hexchar (value >> 12);
+	      s[9] = hexchar (value >> 8);
+	      s[10] = hexchar (value >> 4);
+	      s[11] = hexchar (value);
+	      s[12] = '\r';
+	      s[13] = '\n';
+	      if (stream_send (st, s, 14) < 0)
 		break;
 	    }
author	NIIBE Yutaka <gniibe@fsij.org>	2016-04-19 15:58:26 +0900
committer	NIIBE Yutaka <gniibe@fsij.org>	2016-04-19 15:58:26 +0900
commit	7c2cdaa6e40999d1194cc7188742f0c21acfa0da (patch)
tree	0b70c3be9d96745a4b4b3571e813cf807f81a23b /example-fs-bb48
parent	0bbb43dd3a943285ffb5462db468f7af29c4bbfb (diff)