1 files changed, 84 insertions, 0 deletions
diff --git a/demo/keypad_display.c b/demo/keypad_display.c
new file mode 100644
index 0000000..e6cadf6
--- /dev/null
+++ b/demo/keypad_display.c
@@ -0,0 +1,84 @@
+/**
+ * Demonstration code for MCU 8051 IDE
+ *
+ * Create virtual multiplexed LED display
+ * [Main menu] -> [Virtual HW] -> [Open]
+ * and open file keypad_display.vhw .
+ * Then press F2 and F9 to start simulation.
+ *
+ * Notes:
+ *	F9 - stop simulation
+ *	F2 - shutdown simulator
+ *
+ * @file keypad_display.c
+ */
+
+#include <8051.h>
+#define USE_INLINE_ASM 1
+
+static const char keypad[] = {
+  0xEF, 0xDF, 0xBF, 0x7F
+};
+static const char display_0[] = {
+  0xf9, 0x64, 0x70, 0x48
+};
+static const char display_1[] = {
+  0x59, 0x52, 0x42, 0x40
+};
+static const char display_2[] = {
+  0xf8, 0x40, 0x50, 0xc6
+};
+static const char display_3[] = {
+  0x79, 0xc0, 0x49, 0xc0
+};
+
+char state;
+int row;
+
+int main()
+{
+  while(1) {
+    for(row=0; row<4; row++) {
+      P1=keypad[row];
+
+      #if USE_INLINE_ASM
+        // Inline assembler
+        _asm
+          mov	_state, P1
+        _endasm;
+      #else
+        state=P1;
+      #endif
+
+      state&=0x0f;
+      state^=0x0f;
+
+      if(state & 1) {
+        state=0;
+      } else if(state & 2) {
+        state=1;
+      } else if(state & 4) {
+        state=2;
+      } else if(state & 8) {
+        state=3;
+      } else {
+        continue;
+      }
+
+      switch(row) {
+        case 0:
+          P3=display_0[state];
+          break;
+        case 1:
+          P3=display_1[state];
+          break;
+        case 2:
+          P3=display_2[state];
+          break;
+        case 3:
+          P3=display_3[state];
+          break;
+      }
+    }
+  }
+}