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javi.ar
Joined: 17 Feb 2006 Posts: 59 Location: Argentina
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PIC18 Series and TFT question |
Posted: Thu Jan 17, 2013 9:23 am |
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Hi, I am developing a board which has a TFT LCD Touch screen 2.4". I have to dispay temp & time (and couple of motor spin and heaters )
The question is, will 18F series will be able to handle the display? (in terms of speed ) I was thinking of using 18F87K22, has 67 I/O, 128K flash memory, 4K Ram and 1K eeprom, 16Mhz internal oscillator.
Or I should move to a PIC24/32 series?
Thanks in advance, wait for your opinions. |
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Ttelmah
Joined: 11 Mar 2010 Posts: 19535
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Posted: Thu Jan 17, 2013 10:27 am |
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Yes, easily.
Assuming something like a graphic controller, you can drive an LCD like this from PIC's dozen's of times slower than this.
The big question is what else it has to do. There is a big difference (for example, between just reading temperatures and displaying them, and doing something like PID.
Best Wishes |
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temtronic
Joined: 01 Jul 2010 Posts: 9240 Location: Greensville,Ontario
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Posted: Thu Jan 17, 2013 10:29 am |
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Seems like overkill to me, but what is the TFT interface? SPI,I2C,XXX????
Then again I use the 18F46K22 for 99% of my projects...big or small.
Can't be a whole lot of pixels on a 2.4" screen and LCDs are generally slow, so really, you'll have to read the datasheet,check timing specs and figure it out.
I'd search the web, checking for articles about using your LCD.Remember you're not the first one using it!
hth
jay |
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javi.ar
Joined: 17 Feb 2006 Posts: 59 Location: Argentina
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Posted: Thu Jan 17, 2013 11:12 am |
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temtronic wrote: | Seems like overkill to me, but what is the TFT interface? SPI,I2C,XXX????
Then again I use the 18F46K22 for 99% of my projects...big or small.
Can't be a whole lot of pixels on a 2.4" screen and LCDs are generally slow, so really, you'll have to read the datasheet,check timing specs and figure it out.
I'd search the web, checking for articles about using your LCD.Remember you're not the first one using it!
hth
jay |
Interfaces is 16 bits parallel.
Thanks and you people are right , I´ll try to experience and then decide, thare are 5 18F87K22 on its way ... So I will test with them , now more confident since you mention that you are using it a lot... that is a good referrence to me. Thanks a lot guys... |
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MikeW
Joined: 15 Sep 2003 Posts: 184 Location: Warrington UK
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Posted: Tue Jan 22, 2013 6:56 am |
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I have done a project using a PIC18F, 320x240 TFT with touchscreen.
I used the 8 bit wide data bus, and it is fine. |
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javi.ar
Joined: 17 Feb 2006 Posts: 59 Location: Argentina
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Posted: Tue Jan 22, 2013 7:14 am |
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MikeW wrote: | I have done a project using a PIC18F, 320x240 TFT with touchscreen.
I used the 8 bit wide data bus, and it is fine. |
Let me ask you about the drivers, that is a worry to me, since I might not have enough time to develop one from scratch.
Thanks a lot |
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temtronic
Joined: 01 Jul 2010 Posts: 9240 Location: Greensville,Ontario
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Posted: Tue Jan 22, 2013 9:02 am |
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Sounds like a very ambitious project, worthy of 3-6 months of coding.
Depending on the time left and your skill level it might not be doable.
You could 'google' your LCD module and see what results come back. Odds are real good the mfr or someone has used it before, written drivers (even BASIC ones) that could be modified to CCS C.
If you use the proper 'keywords'. Google is very fast at finding exactly what you need.
hth
jay |
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MikeW
Joined: 15 Sep 2003 Posts: 184 Location: Warrington UK
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Posted: Tue Jan 22, 2013 11:18 am |
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The driver shouldn't be much of a problem.
Find out what chip it is, probably an IL92xx, or SSDxxx
or whatever, then google to find loads of sample code, then massage it into PIC/CCS.
It took me several weeks, and I wrote my own circle, font routines based on GLCD stuff.
My application has a display window with nice temperature settings and actuals, and with the touchscreen (easy to do).
I implemented context sensitive virtual keyboard or entering new setpoints etc. |
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javi.ar
Joined: 17 Feb 2006 Posts: 59 Location: Argentina
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Posted: Tue Jan 22, 2013 11:35 am |
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Thanks for the update. very kind |
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bkamen
Joined: 07 Jan 2004 Posts: 1615 Location: Central Illinois, USA
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Posted: Tue Jan 22, 2013 5:55 pm |
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MikeW wrote: | The driver shouldn't be much of a problem.
Find out what chip it is, probably an IL92xx, or SSDxxx
or whatever, then google to find loads of sample code, then massage it into PIC/CCS.
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This is very important that's getting glossed over.
You can engage an LCD with an interface that requires you drive the LCD completely.
THIS IS NOT WHAT YOU WANT.
For a PIC18F to really get stuff done, you want to be talking to an onboard LCD controller where it has a display memory buffer and you basically tell that controller where in its own memory you want the pixels to be and what color.
IF you STOP talking to the "LCD" for a few seconds or all day - it won't matter as the LCD's controller does all the display timing.
If the PIC has to do the display timing, be ready for a world of performance hurt.
So. Does your LCD have a controller built in, or does the host have to drive everything.
This is an important distinction. _________________ Dazed and confused? I don't think so. Just "plain lost" will do. :D |
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javi.ar
Joined: 17 Feb 2006 Posts: 59 Location: Argentina
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Posted: Mon Mar 04, 2013 9:54 am |
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Yes it has the internal controller ILI9325, I will now make the PCB for connecting and debugging. I will let you know how did it work. I will start with the driver, now that I know which controller has on it. I might try to port it from Microchip. Thanks guys I´ll keep you updated. Thanks for your help and time... |
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