1 files changed, 56 insertions, 0 deletions
diff --git a/src/sdram_test.c b/src/sdram_test.c
new file mode 100644
index 0000000..ba1be8d
--- /dev/null
+++ b/src/sdram_test.c
@@ -0,0 +1,56 @@
+#include <io.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include "system.h"
+
+
+#define msleep(msec) usleep(1000*msec);
+
+pio_write (unsigned int data)
+{
+  IOWR (PIO_0_BASE, 0, data);
+}
+
+static void
+show (int v)
+{
+  // int to seven segment lookup: MSB dp g f e d c b a LSB
+  const uint8_t lookup[10] =
+    { 0x3F, 0x6, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x7, 0x7F, 0x6F };
+
+  uint8_t pio = 0;
+
+  // show negative with DP
+  if (v < 0)
+    {
+      pio |= 0x80;
+      v = -v;
+    }
+
+  if (v > 9)
+    v = 9;
+
+  pio |= lookup[v];
+
+  pio_write (pio);
+}
+
+
+
+int
+main (void)
+{
+  int i;
+  printf ("Working...\n");
+  for (;;) {
+  for (i=-9;i<10;++i) {
+	printf("Showing %d\n",i);
+	show(i);
+	msleep(1000);
+  }
+ }
+	
+}