Driving a 20T202DA2JA VFD, using the (powered) RTC, pressing a button to ask the user to enter the date details over serial, displaying the date on the VFD. Now with added ethernet and NTP to update the time automatically on startup.
Dependencies: EthernetNetIf mbed DNSResolver NTPClientMin
main.cpp
- Committer:
- u0421793
- Date:
- 2010-11-24
- Revision:
- 1:abc0162903bf
- Parent:
- 0:3ba54e2bf65d
- Child:
- 2:f33d74cebc4c
File content as of revision 1:abc0162903bf:
#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 // Also, I have fitted a battery on my breadboard to the RTC, to keep the time across power downs. // VFD SPI spi(p5, p6, p7); // mosi, miso, sclk (miso not used by display) DigitalOut cs(p8); // chip select (active low) // button (push) DigitalIn set_the_time_button (p30); // “set the time” button (active low, pullup resistor) 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 } tm ASK_FOR_THE_TIME(struct tm t) { // 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 //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 return t; } // 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 while (1) { struct tm t; if (set_the_time_button == false) { ASK_FOR_THE_TIME(t); } time_t rtc_seconds = time(NULL); // somehow gets the current amount of seconds, evah! 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 // 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)) { // if the date is below the 10th or above the 20th 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. } } 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); } }