Diff: main.cpp

Revision:

0:3ba54e2bf65d

Child:

1:abc0162903bf

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Sat Nov 13 23:42:18 2010 +0000
@@ -0,0 +1,147 @@
+#include "mbed.h"
+
+// rudimentary driving of a 20T202DA2JA vacuum fluorescent display, 20 chars x 2 lines
+// display has 5 pins
+// 1 - green - GND
+// 2 - yellow - Vcc
+// 3 - orange - SIO - serial data - MOSI - p5
+// 4 - red - /STB - active low device select - p8
+// 5 - brown - SCK - serial clock - sclk - p7
+
+// VFD
+SPI spi(p5, p6, p7); // mosi, miso, sclk (miso not used by display)
+DigitalOut cs(p8); // chip select (active low)
+
+void DATA(unsigned char displaying) {
+    // Select the device by setting chip select low
+    cs = 0;
+    spi.write(0xfa);
+    spi.write(displaying);
+    // Deselect the device
+    cs = 1;
+}
+
+void COM(unsigned char telling) {
+    // Select the device by setting chip select low
+    cs = 0;
+    spi.write(0xf8);
+    spi.write(telling);
+    // Deselect the device
+    cs = 1;
+}
+
+void INITIALISE_DISPLAY() {
+    COM(0x01); //clear all display and set DD-RAM address 0 in address counter
+    COM(0x02); //move cursor to the original position
+    COM(0x06); //set the cursor direction increment and cursor shift enabled
+    COM(0x38); //set 8bit operation,2 line display and 100% brightness level
+    COM(0x80); //set cursor to the first position of 1st line
+    COM(0x0c); //set display on,cursor on,blinking off
+}
+
+// spare display testing string
+// char theString[41] = {"20T202DA2JA VFD driven by mbed using SPI"}; // forty characters max
+char timeStringTop[21], timeStringBottom1[3], timeStringBottom2[17]; // string to put the time representation into
+
+char day_suffix[3] =  "th"; // suffix string for days like 1st 2nd 3rd
+char first[3]= "st", second[3] = "nd", third[3] = "rd"; // holding strings for the suffixes
+
+int main() {
+    // Setup the spi for 8 bit data, high steady state clock,
+    // second edge capture, with a 1MHz clock rate
+    spi.format(8,3); // set SPI mode
+    spi.frequency(1000000);
+
+    INITIALISE_DISPLAY(); // call the function that initialises the VFD
+
+    // get the current time from the terminal by asking the user to enter
+    // unfortunately, there's no echo back, so they can't see what they type
+    struct tm t;
+    //year
+    printf("Enter year:\n"); // ask to enter year
+    printf("YYYY[enter]\n"); // as YYYY
+    scanf("%d", &t.tm_year); // put the typing into here
+
+    //month
+    printf("Enter month:\n"); // ask to enter month
+    printf("MM[enter]\n"); // as MM
+    scanf("%d", &t.tm_mon); // put the typing into here
+
+    //date
+    printf("Enter date:\n"); // ask to enter date
+    printf("DD[enter]\n"); // as DD
+    scanf("%d", &t.tm_mday); // put the typing into here
+
+    //hours
+    printf("Enter hours:\n"); // ask to enter hours
+    printf("HH[enter]\n"); // as HH
+    scanf("%d", &t.tm_hour); // put the typing into here
+
+    //minutes
+    printf("Enter minutes:\n"); // ask to enter minutes
+    printf("MM[enter]\n"); // as MM
+    scanf("%d", &t.tm_min); // put the typing into here
+
+    //seconds
+    printf("Enter seconds:\n"); // ask to enter seconds
+    printf("SS[enter]\n"); // as SS
+    scanf("%d", &t.tm_sec); // put the typing into here
+
+    // adjust for tm structure required values
+    t.tm_year = t.tm_year - 1900;
+    t.tm_mon = t.tm_mon - 1;
+
+    // set the time
+    set_time(mktime(&t));
+    //set_time(1289676600);  // Set RTC time to Sat, 13 Nov 2010 19:30:00 in case of testing
+
+    while (1) {
+
+        time_t rtc_seconds = time(NULL); // somehow gets the current amount of seconds, evah!
+
+        // first do a quick check to see if our date needs a 'st'; 'nd'; 'rd' or 'th' suffix
+        if (t.tm_mday < 10 | t.tm_mday > 20) {
+            switch (t.tm_mday%10) {
+                case 1:
+                    strcpy (day_suffix,first); // is it a day that needs a "st"?
+                    break;
+                case 2:
+                    strcpy (day_suffix,second); // is it a day that needs a "nd"
+                    break;
+                case 3:
+                    strcpy (day_suffix,third); // is it a day that needs a "rd"
+                    break;
+                default:
+                    break; // leave 'day_suffix' saying "th" then.
+            }
+        }
+
+        int i = 0; // initalise the character steppers
+
+        // build the two lines of the display separately
+        strftime(timeStringTop, 20, "%X %A %p  ", localtime(&rtc_seconds)); // put the hours:minutes:seconds, then full day, then am/pm
+
+        COM(0x80); // first line
+        for (i=0; i<20; i++) {
+            DATA(timeStringTop[i]); // step through the top line
+        }
+
+        // this builds the second line in three pieces
+        strftime(timeStringBottom1, 2, "%e", localtime(&rtc_seconds)); // put the date in
+        strftime(timeStringBottom2, 16, " %B %Y  ", localtime(&rtc_seconds)); // put a space then the full month then the year then spaces
+
+        COM(0xc0); // second line
+        for (i=0; i<2; i++) {
+            DATA(timeStringBottom1[i]); // step through the first part of the bottom line
+        }
+        for (i=0; i<2; i++) {
+            DATA(day_suffix[i]); // then add the day suffix
+        }
+        for (i=0; i<17; i++) {
+            DATA(timeStringBottom2[i]); // finish stepping through the bottom line
+        }
+
+        wait(1);
+    }
+
+}
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