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Message |
jamalavedra
Joined: 25 Oct 2016
Posts: 62
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| GLCD writing problem |
 Posted: Thu Jan 26, 2017 5:25 am |
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| Code: |
void glcd_blank() {
unsigned int16 p = 0, c = 0;
for(p = 0; p < 8; p++)
{
glcd_command(0xB0 | p);
for(c = 0; c < 129; c++)
{
glcd_command(0x10 | (c & 0xf));
glcd_command(0x00 | ((c >> 4) & 0xf));
glcd_data(0x00);
}
}
}
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I have worked out how to initialize the GLCD and attached above you'll see the code in order to clear the display. But I haven't find out how to write stuff at the screen. This is the code I am using. Help!
| Code: |
glcd_init();
delay_ms(1000);
glcd_blank();
delay_ms(1000);
glcd_contrast(3, 25);
while(1)
{
glcd_pixel(1, 1, 1);
glcd_pixel(2, 1, 1);
glcd_pixel(1, 2, 1);
glcd_pixel(2, 2, 1);
delay_ms(2000);
// Clear a pixel in the RAM buffer
glcd_pixel(64, 64, 0);
delay_ms(1000);
glcd_refresh();
}
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temtronic
Joined: 01 Jul 2010
Posts: 9229
Location: Greensville,Ontario
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| Posted: Thu Jan 26, 2017 6:45 am |
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One HUGE problem is that WE do not know what GLCD you're using ! We can't test your code as the commands may not be the same. Also we need to know the PIC, compiler version and if this is real hardware or a 'simulation'.
There are GLCD drivers for CCS,again need to know what GLCD you're using.
Simple start though...does the GLCD power up into reset and look 'ready'. Now how that is supposed to be, again is in the datasheet.
If you have a 162 or 204 LCD module does that work with your PIC?
perhaps the PIC is bad? a wiring issue ?
bottom line we need a lot more information before we can help !
Jay |
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jamalavedra
Joined: 25 Oct 2016
Posts: 62
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| Posted: Thu Jan 26, 2017 6:48 am |
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totally my fault. I am using the 18F2685 PIC and the GLCD I am using is the EA DOGM128W-6, datasheet avaliable in the following link http://www.qscomp.cz/Pdf/dogm128e.pdf.
The inicialitazion voltatges at every pin are fine and the clear screen process seems to work just fine, but the writting process is apparently a problem right now. |
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temtronic
Joined: 01 Jul 2010
Posts: 9229
Location: Greensville,Ontario
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| Posted: Thu Jan 26, 2017 7:21 am |
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This is easy....
5 volt PIC, 3 volt GLCD
That PIC will NOT function at 3 volts, so you need to either
1) choose the 'L' version of that PIC
2) choose a real 3 volt PIC ( like 18F46K22)
3) add logic level conversion devices to properly covert 5 to 3 and 3 to 5.
4) buy a GLCD that IS rated for 5 volt operation
5) ??
You'll find that most peripheral devices these days(GLCD,GPS,etc...) are designed for 3 volts so it is CRITCAL to design the project with the
correct interface to whatever PIC you've chosen to use.
Perhaps the easiest solution is to use the 'L' version.That way your code is 100% compatible and no additional wiring of parts to the project.
Jay |
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jamalavedra
Joined: 25 Oct 2016
Posts: 62
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| Posted: Thu Jan 26, 2017 7:30 am |
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| I see your point, but this PIC can work at 3V. I have been trying it out and the PIC has been working fine with a 3V source. Thus, the outputs connected to the display are also 3V. I believe this shouldnt be a problem and the mistake has to be in the code. |
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temtronic
Joined: 01 Jul 2010
Posts: 9229
Location: Greensville,Ontario
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| Posted: Thu Jan 26, 2017 8:28 am |
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According to Figure 21-1 of the datasheet 39761b.pdf that PIC is NOT designed or rated to run at less than 4.2 volts. Just because yours 'works' now doesn't mean it will tomorrow or another one will today. Several of the internal peripherals,like the ADC, will not be operating 'right' and over time and or temperature, the PIC will fail or give 'odd' results.
Jay |
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