I’ve been working on a program that displays the current time and date on a Sure Electronics 24x16 display. The day of week, month, date, and year are display are constantly scrolling across the top of the display while the time is displayed on the bottom. When I start it up and sync it with the current PC time everything goes great. I can connect it to a battery of wall wort and let it do its thing. After about five minutes it will go blank or the time will be reset. The same thing happens when I leave it connected usb to the PC. Can anyone tell me whats going on? I feel the way I’m running the code interferes with the clock code going on in the background. Can anyone give me any advice? Ill post my code below…
/***********************************************************************
* demo16x24.c - Arduino demo program for Holtek HT1632 LED driver chip,
* As implemented on the Sure Electronics DE-DP016 display board
* (16*24 dot matrix LED module.)
* Nov, 2008 by Bill Westfield ("WestfW")
* Copyrighted and distributed under the terms of the Berkely license
* (copy freely, but include this notice of original author.)
***********************************************************************/
#include <DateTime.h>
#include <DateTimeStrings.h>
#include <WString.h> // include the String library
#include "ht1632.h"
#include <avr/pgmspace.h>
#include "font.h"
#define TIME_MSG_LEN 11 // time sync to PC is HEADER followed by unix time_t as ten ascii digits
#define TIME_HEADER 255
#define maxLength 40
#define X_MAX 23
#define Y_MAX 15
#define ASSERT(condition) //nothing
/*
* Set these constants to the values of the pins connected to the SureElectronics Module
*/
static const byte ht1632_data = 10; // Data pin (pin 7)
static const byte ht1632_wrclk = 11; // Write clock pin (pin 5)
static const byte ht1632_cs = 12; // Chip Select (1, 2, 3, or 4)
// There should also be a common GND.
// The module with all LEDs like draws about 200mA,
// which makes it PROBABLY powerable via Arduino +5V
#define DEMOTIME 10000 // 30 seconds max on each demo is enough.
#define DISPDELAY 40 // Each "display" lasts this long
#define LONGDELAY 1000 // This delay BETWEEN demos
String inString = String(maxLength); // allocate a new String
/***********************************************************************
* ht1632_chipselect / ht1632_chipfree
* Select or de-select a particular ht1632 chip.
* De-selecting a chip ends the commands being sent to a chip.
* CD pins are active-low; writing 0 to the pin selects the chip.
***********************************************************************/
void ht1632_chipselect(byte chipno)
{
DEBUGPRINT("\nHT1632(%d) ", chipno);
digitalWrite(chipno, 0);
}
void ht1632_chipfree(byte chipno)
{
DEBUGPRINT(" [done %d]", chipno);
digitalWrite(chipno, 1);
}
/*
* ht1632_writebits
* Write bits (up to 8) to h1632 on pins ht1632_data, ht1632_wrclk
* Chip is assumed to already be chip-selected
* Bits are shifted out from MSB to LSB, with the first bit sent
* being (bits & firstbit), shifted till firsbit is zero.
*/
void ht1632_writebits (byte bits, byte firstbit)
{
DEBUGPRINT(" ");
while (firstbit) {
DEBUGPRINT((bits&firstbit ? "1" : "0"));
digitalWrite(ht1632_wrclk, LOW);
if (bits & firstbit) {
digitalWrite(ht1632_data, HIGH);
}
else {
digitalWrite(ht1632_data, LOW);
}
digitalWrite(ht1632_wrclk, HIGH);
firstbit >>= 1;
}
}
/*
* ht1632_sendcmd
* Send a command to the ht1632 chip.
* A command consists of a 3-bit "CMD" ID, an 8bit command, and
* one "don't care bit".
* Select 1 0 0 c7 c6 c5 c4 c3 c2 c1 c0 xx Free
*/
static void ht1632_sendcmd (byte command)
{
ht1632_chipselect(ht1632_cs); // Select chip
ht1632_writebits(HT1632_ID_CMD, 1<<2); // send 3 bits of id: COMMMAND
ht1632_writebits(command, 1<<7); // send the actual command
ht1632_writebits(0, 1); /* one extra dont-care bit in commands. */
ht1632_chipfree(ht1632_cs); //done
}
/*
* ht1632_senddata
* send a nibble (4 bits) of data to a particular memory location of the
* ht1632. The command has 3 bit ID, 7 bits of address, and 4 bits of data.
* Select 1 0 1 A6 A5 A4 A3 A2 A1 A0 D0 D1 D2 D3 Free
* Note that the address is sent MSB first, while the data is sent LSB first!
* This means that somewhere a bit reversal will have to be done to get
* zero-based addressing of words and dots within words.
*/
static void ht1632_senddata (byte address, byte data)
{
ht1632_chipselect(ht1632_cs); // Select chip
ht1632_writebits(HT1632_ID_WR, 1<<2); // send ID: WRITE to RAM
ht1632_writebits(address, 1<<6); // Send address
ht1632_writebits(data, 1<<3); // send 4 bits of data
ht1632_chipfree(ht1632_cs); // done
}
void ht1632_setup()
{
pinMode(ht1632_cs, OUTPUT);
digitalWrite(ht1632_cs, HIGH); /* unselect (active low) */
pinMode(ht1632_wrclk, OUTPUT);
pinMode(ht1632_data, OUTPUT);
ht1632_sendcmd(HT1632_CMD_SYSDIS); // Disable system
ht1632_sendcmd(HT1632_CMD_COMS11); // 16*32, PMOS drivers
ht1632_sendcmd(HT1632_CMD_MSTMD); /* Master Mode */
ht1632_sendcmd(HT1632_CMD_SYSON); /* System on */
ht1632_sendcmd(HT1632_CMD_LEDON); /* LEDs on */
for (byte i=0; i<96; i++)
ht1632_senddata(i, 0); // clear the display!
delay(LONGDELAY);
}
/*
* we keep a copy of the display controller contents so that we can
* know which bits are on without having to (slowly) read the device.
* Note that we only use the low four bits of the shadow ram, since
* we're shadowing 4-bit memory. This makes things faster, and we
* use the other half for a "snapshot" when we want to plot new data
* based on older data...
*/
byte ht1632_shadowram[96]; // our copy of the display's RAM
/*
* plot a point on the display, with the upper left hand corner
* being (0,0), and the lower right hand corner being (23, 15).
* Note that Y increases going "downward" in contrast with most
* mathematical coordiate systems, but in common with many displays
* No error checking; bad things may happen if arguments are out of
* bounds! (The ASSERTS compile to nothing by default
*/
void ht1632_plot (char x, char y, char val)
{
char addr, bitval;
ASSERT(x >= 0);
ASSERT(x <= X_MAX);
ASSERT(y >= 0);
ASSERT(y <= y_MAX);
if(y < 0 || y > Y_MAX || x < 0 || x > X_MAX){
return;
}
/*
* The 4 bits in a single memory word go DOWN, with the LSB
* (first transmitted) bit being on top. However, writebits()
* sends the MSB first, so we have to do a sort of bit-reversal
* somewhere. Here, this is done by shifting the single bit in
* the opposite direction from what you might expect.
*/
bitval = 8>>(y&3); // compute which bit will need set
addr = (x<<2) + (y>>2); // compute which memory word this is in
if (val) { // Modify the shadow memory
ht1632_shadowram[addr] |= bitval;
}
else {
ht1632_shadowram[addr] &= ~bitval;
}
// Now copy the new memory value to the display
ht1632_senddata(addr, ht1632_shadowram[addr]);
}
/*
* get_shadowram
* return the value of a pixel from the shadow ram.
*/
byte get_shadowram(byte x, byte y)
{
byte addr, bitval;
bitval = 8>>(y&3); // compute which bit will need set
addr = (x<<2) + (y>>2); // compute which memory word this is in
return (0 != (ht1632_shadowram[addr] & bitval));
}
/*
* snapshot_shadowram
* Copy the shadow ram into the snapshot ram (the upper bits)
* This gives us a separate copy so we can plot new data while
* still having a copy of the old data. snapshotram is NOT
* updated by the plot functions (except "clear")
*/
void snapshot_shadowram()
{
for (char i=0; i< sizeof ht1632_shadowram; i++) {
ht1632_shadowram[i] = (ht1632_shadowram[i] & 0x0F) | ht1632_shadowram[i] << 4; // Use the upper bits
}
}
/*
* get_snapshotram
* get a pixel value from the snapshot ram (instead of
* the actual displayed (shadow) memory
*/
byte get_snapshotram(byte x, byte y)
{
byte addr, bitval;
bitval = 128>>(y&3); // user upper bits!
addr = (x<<2) + (y>>2); // compute which memory word this is in
if (ht1632_shadowram[addr] & bitval)
return 1;
return 0;
}
/*
* ht1632_clear
* clear the display, and the shadow memory, and the snapshot
* memory. This uses the "write multiple words" capability of
* the chipset by writing all 96 words of memory without raising
* the chipselect signal.
*/
void ht1632_clear()
{
char i;
ht1632_chipselect(ht1632_cs); // Select chip
ht1632_writebits(HT1632_ID_WR, 1<<2); // send ID: WRITE to RAM
ht1632_writebits(0, 1<<6); // Send address
for (i = 0; i < 96/2; i++) // Clear entire display
ht1632_writebits(0, 1<<7); // send 8 bits of data
ht1632_chipfree(ht1632_cs); // done
for (i=0; i < 96; i++)
ht1632_shadowram[i] = 0;
}
/***********************************************************************
* plotting routines built on top of "dot" capabiliy of ht1632_plot().
* Code past here is not particularly dependent on the underlying
* graphics hardware
***********************************************************************/
#define plot(x,y,v) ht1632_plot(x,y,v)
#define cls ht1632_clear
// End part One