Diff: vfd.cpp

Revision:

3:7fca72f96711

Child:

4:7087ea3d13c1

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vfd.cpp	Thu Aug 23 00:17:04 2012 +0000
@@ -0,0 +1,141 @@
+/*
+ * The VFD code
+ *
+ * for a futuba M204LD01AA
+ * 
+ *
+ * p27 -> input, busy
+ * p28 -> serial data in
+ * p29 -> clock 
+ * p30 -> latch
+ *
+ *
+ */
+
+#include "mbed.h"
+#include "vfd.h"
+
+// InturruptIn busy_intr(p27)
+
+DigitalIn  vfd_p_busy(p27);
+DigitalOut vfd_p_data(p28);
+DigitalOut vfd_p_clock(p29);
+DigitalOut vfd_p_latch(p30);
+
+/* current state */
+int  c_data;
+bool c_a0;
+bool c_blank;
+
+void vfd_shift_clock(void) {
+        vfd_p_clock = 0;
+        wait_us(100);
+        vfd_p_clock = 1;
+        wait_us(100);
+}
+
+void vfd_doit(int data, int mode, int wr, int ss) {
+    int i, bit;
+    
+    vfd_p_data = 0; // nc
+    vfd_shift_clock();
+    vfd_p_data = 0; // nc
+    vfd_shift_clock();
+
+    vfd_p_data = 1; // reset, 0 = in reset
+    vfd_shift_clock();
+
+    vfd_p_data = c_blank; // Blank, 0 = blanked
+    vfd_shift_clock();
+    
+    vfd_p_data = ss; // SS, clockish
+    vfd_shift_clock();
+
+    vfd_p_data = 1; // rd
+    vfd_shift_clock();
+
+    vfd_p_data = mode; // A0, data/command
+    vfd_shift_clock();
+
+    vfd_p_data = wr; // WR
+    vfd_shift_clock();
+
+    for (i = 0 ; i < 8; i++) {
+        bit = (data & (1 << i)) >> i;
+        vfd_p_data = bit;
+        vfd_shift_clock();
+    }
+        
+    vfd_p_latch = 0;
+    wait_us(10);
+    vfd_p_latch = 1;
+    wait_us(10);
+}
+
+/* mode == 1 if command */
+void vfd_send(int data, int mode)
+{
+    data = data & 0xff;
+    c_data = data;
+    c_blank = 1;
+
+    if (vfd_p_busy)
+        printf("pre, busy: %d\r\n", vfd_p_busy.read());
+    
+    if (vfd_p_busy)
+    {
+        wait_ms(4); // should loop, 3.1 ms is max according to the data sheet.
+        if (vfd_p_busy)
+        {
+            printf("still busy :(\r\n");
+            return;
+        }
+    }
+    
+    /* wr,ss */
+    vfd_doit(data, mode, 0, 0);
+    wait_us(1);
+    vfd_doit(data, mode, 1, 0);
+    wait_us(1);
+    vfd_doit(data, mode, 1, 1);
+    wait_us(1);
+
+    if (vfd_p_busy)
+        printf("post1, busy: %d\r\n", vfd_p_busy.read());
+
+    vfd_doit(data, mode, 0, 0);
+    wait_ms(1); // loop and wait for not busy
+
+    if (vfd_p_busy)
+        printf("post2, busy: %d\r\n", vfd_p_busy.read());
+
+    while (vfd_p_busy) {
+        wait_us(250);
+        printf("post-while, busy: %d\r\n", vfd_p_busy.read());
+    }
+}
+
+void vfd_command(int data) {
+    vfd_send(data, 1);
+}
+
+void vfd_data(int data) {
+    vfd_send(data, 0);
+}
+
+void vfd_init(void) {
+    vfd_data(0x0c); // clear
+    vfd_data(0x1b); // esc
+    vfd_data(0);    // v pos
+    vfd_data(0);    // h pos
+}
+
+void vfd_blank(void) {
+    /* blank */
+}
+
+void vfd_show(void) {
+    /* unblank */
+}
+
+