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Ariba
Registered Member

Date Joined Apr 2007
Total Posts : 712

Posted 12/10/2009 11:21 PM (GMT -7)

Cluso99 said...
I like the idea of a 6x8 character option for 80 chars/line (5x7 with a blank pixel). This is what was originally used in the 70's & 80's. The characters will be blocky, but hey, we lived with that for many years, and the LCD is a much better display than the old monitors.

But this old monitors were much bigger then this 4.3" LCD.
I tried 6x8 font with the HiRes Bitmap driver, and found that the characters are so tiny that I can not read it comfortably (perhaps it's time for glasses...). So I tried to double every pixel, but then the characters were unnecessray big, and only 40 fit in a line.

So I was thinking 8x8, 8x12 or 8x16 would be a good compromise.
The actual driver I work on, can switch between 8x8 and 8x16 uses the Atari font and allows separate colors for every character.

It would be quiet easy to change it to 6x8 / 6x16, but I don't have a 6x8 font organized as 8 bytes (1 byte per row) to try it.

Andy

FlyingFishFinger
Registered Member

Date Joined Apr 2005
Total Posts : 452

Posted 12/10/2009 11:50 PM (GMT -7)

How hard would it be to make the driver write along the short side of the display? I'm contemplating a PDA-style readout device which would be held upright rather than across.

Rafael

UC Berkeley '12 EECS
CalSol: Berkeley Solar Car team
www.calsol.berkeley.edu
KJ6AWU

Eagleman
Registered Member

Date Joined Nov 2009
Total Posts : 22

Posted 12/12/2009 12:16 AM (GMT -7)

Rayman,

On the 4.3" display, if the power supply for LED+ and Vdd were intentionally shut down without stopping the signals from the Prop, would that destroy the LCD by having signal levels to the LCD that were greater than Vdd (0 volts)?

I ask because my devices are battery powered (LI-Ion rechargeable) and in an effort to conserve power I like the devices to automatically turn off or cut back on consumed power when not actively in use. If we can remove LCD power, we can still use touchscreen depressions to "wake-up" the LCD. This would be just one method of conserving battery charge.

mctrivia
Registered Member

Date Joined Jan 2009
Total Posts : 3482

Posted 12/12/2009 12:22 AM (GMT -7)

the backlight is just 10 leds in series it is safe to remove power from them and both mine and rays breakout boards use a driver chip with a disable option. The LCD itself should not draw much power if not enabled and you can use the PI pin on the breakout board to allow for an easy wake method.

24 bit LCD Breakout Board now in. $21.99 has backlight driver and touch sensitive decoder.

Rayman
Registered Member

Date Joined Jul 2007
Total Posts : 3127

Posted 12/12/2009 5:43 AM (GMT -7)

true

My Prop Info&Apps: http://www.rayslogic.com/propeller/propeller.htm

Eagleman
Registered Member

Date Joined Nov 2009
Total Posts : 22

Posted 12/13/2009 12:14 AM (GMT -7)

Having trouble getting Raymans LCD to work on my PE Education board. Using Ariba's driver to test, I have the following pins hooked up as follows:

P0 B0 (basepin defined as "0")

P1 B1

P2 G0

P3 G1

P4 R0

P5 R1

P6 DE

P7 PCLK

P8 BL

P9 DON

P29 SDA

P28 SCL

PLUS all grounds hooked up

Vdd to +3.3v

VBL to +3.3v

I've got a 20 pin header soldered to Ray's breakout board and that is plugged into an empty area on the PE breadboard with jumpers connecting the 20 pin header rows to the Prop and power.

The assignment for the above pins (and basepin = 0) were made in the DAT section of TSD_Demo.spin.

I get no light or signs of life on the LCD.

I keep seeing referrals to the "Parallax VGA Driver", but can't seem to find any info on it.

I am used to working with PICs and PBP but I am new to spin and the Propeller so I get lost easily.

Any suggestions from the experienced people who had no trouble getting the LCD to work?

Post Edited (Eagleman) : 12/13/2009 7:30:29 AM GMT

Ariba
Registered Member

Date Joined Apr 2007
Total Posts : 712

Posted 12/13/2009 2:28 AM (GMT -7)

Eagleman

It seems you have Hsync and Vsync not connected!
The basepin ist the first pin of a 8 pin group with the following assignement:
+0 VSync
+1 HSync
+2 B0
+3 B1
+4 G0
+5 G1
+6 R0
+7 R1
The Basepin can only be a multiple of 8 (0,8,16,24) because of the VideoHardware in the cog. In your case it will be 0.
So you need to shift the other Pins up, perhaps:
P8 DE
P9 PCLK
P10 BL
P11 DON
P29 SDA
P28 SCL
For this pins you can choose also other free pins.

What is strange is, that also the Backlight not worked, are you sure, that GND and +3.3V are connected right?
Good luck

Andy

Post Edited (Ariba) : 12/13/2009 9:34:19 AM GMT

Ariba
Registered Member

Date Joined Apr 2007
Total Posts : 712

Posted 12/13/2009 2:43 AM (GMT -7)

FlyingFishFinger said...
How hard would it be to make the driver write along the short side of the display? I'm contemplating a PDA-style readout device which would be held upright rather than across.

Rafael

Should be possible. With a 6x8 font you will only get 40 characters per line, but a lot of lines.
What it needs is a 90° rotated font, which I have already, and a different read sequence of the character buffer.

I think this is especially useful for a virtual keyboard on the second half of the screen.

Andy

FlyingFishFinger
Registered Member

Date Joined Apr 2005
Total Posts : 452

Posted 12/13/2009 3:28 AM (GMT -7)

Nice. Precisely what I was thinking. Stylus & keyboard = awesome debugger :) I haven't gotten my breakout from Matt yet so I haven't had a chance to play around with it (not that I've got time between finals, but it's the plan for winter break), which means I don't know anything about this screen besides what I read here and the one I've got sitting in front of me.
Would you be willing to share your font sometime?

Raf

UC Berkeley '12 EECS
CalSol: Berkeley Solar Car team
www.calsol.berkeley.edu
KJ6AWU

Eagleman
Registered Member

Date Joined Nov 2009
Total Posts : 22

Posted 12/13/2009 7:15 AM (GMT -7)

Ariba,

Thanks for your help! I finally have a screen working. Also, with your help I now have a better understanding how the video and spin work. I've got VBL connected to +3.3v; should that be connected to +5v?

Here's my new connection chart (for anyone else that might need this info):
p0 Vsync (basepin)
p1 Hsync
p2 B0
p3 B1
p4 G0
p5 G1
p6 R0
p7 R1
p8 DEN
p9 DE
p10 PCLK
p11 BL
p27 IRQ
p28 SCL
p29 SDA
VBL +3.3v

Where can I find additional information on the basic "Parallax VGA Driver"? I searched the forum archives, but found nothing.

Thanks again for your help. GREATLY appreciated!!
Eagleman

Rayman
Registered Member

Date Joined Jul 2007
Total Posts : 3127

Posted 12/13/2009 12:26 PM (GMT -7)

Eagleman: Glad you got it working! There's some documentation at the bottom of the vga.spin file...

My Prop Info&Apps: http://www.rayslogic.com/propeller/propeller.htm

Rayman
Registered Member

Date Joined Jul 2007
Total Posts : 3127

Posted 12/13/2009 12:27 PM (GMT -7)

We're ready to take orders for the "used" 4.3" touchscreens again. Note that price has increased to $18.
I believe I've sent an email to everyone who was waiting...

My Prop Info&Apps: http://www.rayslogic.com/propeller/propeller.htm

kerryw
Registered Member

Date Joined May 2006
Total Posts : 61

Posted 12/13/2009 12:54 PM (GMT -7)

Ariba said...
OK, here are my Bitmap drivers for the 4.3" LCD.

There are 1 bit per pixel drivers in HiRes- and LowRes versions (480x272 and 240x136 pixels).
The color is definable per 32x32 pixel tile.
HiRes is usefull when you will draw a lot on the screen, but needs 16 kByte memory.
LowRes is mainly for application which has not much RAM free for the screen, LowRes needs only 4.2 kByte.

Then there is also a 2 bit per pixel driver with 240x136 pixels. Every pixel can have 1 of 4 colors. Individual 4 colors
are definable per 48x32 pixel tiles. This gives 5 x 5 tiles, which is a good size for touch buttons. The first line of tiles
is only 10 pixels in height, this can be used for a Titlebar with its own colors.

A demo code is included in the ZIP, which works for all drivers. You just need to change the driver in the OBJ section.
The demo shows the color tiles, and draws pixels and lines. I've tried to make a photo, but my camera is not good
enough, to show details sharp, so perhaps somebody else can make a screenshot.

Andy

Edit: Updated also the comments and description to the right version.

Thanks so much for the drivers Ariba. Did you happen to create a graphics.spin object that support these?

Kerry

"Heaven help me Marge, I'm just not that smart." - Homer Simpson

Harrison.
Registered Member

Date Joined Jul 2004
Total Posts : 474

Posted 12/13/2009 1:19 PM (GMT -7)

These LCDs are great. My partner and I was able to incorporate the LCD into a university project without any problems (thanks to the excellent documentation Rayman provided). The main difference is we chose to use a MCP3202 2-channel ADC instead of a touchscreen controller. The touchscreen reading algorithm was simple enough to implement in software (the hardest part was implementing 3-point calibration).

I would say these are easier to use than the B/W 128x64 graphic LCDs most people use. It only took us about 1.5 weeks from idea to finishing a board layout using this LCD. The board also contains a Freescale 9S12, ethernet interface, and an analog audio front end; which is what took up most of the layout and design time.

Image Attachment :

DSC_1856.JPG 147KB (image/jpeg)

This image has been viewed 119 time(s).

Rayman
Registered Member

Date Joined Jul 2007
Total Posts : 3127

Posted 12/13/2009 2:47 PM (GMT -7)

Very cool! Thanks for sharing the photo and info!

My Prop Info&Apps: http://www.rayslogic.com/propeller/propeller.htm

Rayman
Registered Member

Date Joined Jul 2007
Total Posts : 3127

Posted 12/13/2009 4:39 PM (GMT -7)

Is that some kind of clay connecting the LCD to the board?

My Prop Info&Apps: http://www.rayslogic.com/propeller/propeller.htm

Harrison.
Registered Member

Date Joined Jul 2004
Total Posts : 474

Posted 12/13/2009 4:45 PM (GMT -7)

Rayman said...
Is that some kind of clay connecting the LCD to the board?

Nah, it's just some foam board and hot glue. Nothing too fancy.

Ariba
Registered Member

Date Joined Apr 2007
Total Posts : 712

Posted 12/14/2009 2:05 AM (GMT -7)

kerryw said...

Ariba said...

OK, here are my Bitmap drivers for the 4.3" LCD.

There are 1 bit per pixel drivers in HiRes- and LowRes versions (480x272 and 240x136 pixels).
The color is definable per 32x32 pixel tile.
HiRes is usefull when you will draw a lot on the screen, but needs 16 kByte memory.
LowRes is mainly for application which has not much RAM free for the screen, LowRes needs only 4.2 kByte.

Then there is also a 2 bit per pixel driver with 240x136 pixels. Every pixel can have 1 of 4 colors. Individual 4 colors
are definable per 48x32 pixel tiles. This gives 5 x 5 tiles, which is a good size for touch buttons. The first line of tiles
is only 10 pixels in height, this can be used for a Titlebar with its own colors.

A demo code is included in the ZIP, which works for all drivers. You just need to change the driver in the OBJ section.
The demo shows the color tiles, and draws pixels and lines. I've tried to make a photo, but my camera is not good
enough, to show details sharp, so perhaps somebody else can make a screenshot.

Andy

Edit: Updated also the comments and description to the right version.

Thanks so much for the drivers Ariba. Did you happen to create a graphics.spin object that support these?

Kerry

Kerry

Here is the graphics object that tdeyle posted a few pages before, adapted to my Bitmap drivers.
This is not as good as Chip's graphics.spin, but you can draw graphic and text (picked from the ROM font).

The included Demo is for the HiRes version, if you change the bitmap object, and all the coordinates, then this should
work also with the LowRes driver.

It seems to have some issues if the Y coordinate is higher then the screen.

I will also adapt my own Graphics object later, but not found the time so far.

Andy

File Attachment :
TFT_graphics_DEMO.zip 28KB (application/x-zip-compressed)

This file has been downloaded 78 time(s).

Ariba
Registered Member

Date Joined Apr 2007
Total Posts : 712

Posted 12/16/2009 4:47 PM (GMT -7)

And yet another Graphics driver.

This time it works with Chip's Graphics object. In opposite to Raymans graphics demo for this TFT, this driver
uses the whole screen for a 240x136 pixel bitmap. So every bitmap buffer needs only 8.5 kByte, that allows
also double buffering and lets 7 kByte more memory free than the TV version.

Sorry for the bad photo, I really need a better camera for such photos...

Andy

Image Attachment :

TSDGraphics.jpg 26KB (image/jpeg)

This image has been viewed 95 time(s).

File Attachment :
TSD_GraphicsDemo.zip 26KB (application/x-zip-compressed)

This file has been downloaded 67 time(s).

Rayman
Registered Member

Date Joined Jul 2007
Total Posts : 3127

Posted 12/16/2009 5:39 PM (GMT -7)

Very nice! I think Ariba is as into this as I am now!

My Prop Info&Apps: http://www.rayslogic.com/propeller/propeller.htm

kerryw
Registered Member

Date Joined May 2006
Total Posts : 61

Posted 12/16/2009 5:57 PM (GMT -7)

Ariba said...
And yet another Graphics driver.

This time it works with Chip's Graphics object. In opposite to Raymans graphics demo for this TFT, this driver
uses the whole screen for a 240x136 pixel bitmap. So every bitmap buffer needs only 8.5 kByte, that allows
also double buffering and lets 7 kByte more memory free than the TV version.

Sorry for the bad photo, I really need a better camera for such photos...

Andy

Great work Ariba! Thanks so much.

Kerry

"Heaven help me Marge, I'm just not that smart." - Homer Simpson

Eagleman
Registered Member

Date Joined Nov 2009
Total Posts : 22

Posted 12/16/2009 6:15 PM (GMT -7)

Great work, Ariba!! I have another tool to use with Ray's LCDs in learning how this mysterious SPIN stuff works. I tried to take a picture of the display for you, but it runs too quickly - they all came out blurred. Is there a way to slow it down for a slower lens?

Ariba
Registered Member

Date Joined Apr 2007
Total Posts : 712

Posted 12/17/2009 12:44 AM (GMT -7)

Thanks guys

There are some wrong comments in the Driver file (just copied from a 2 bit driver and forgot to change).
So I attach a polished version. The code has not changed, only some description. If you don't want study
the driver you don't need to update it.

Eagleman
You can add the following line after the last line of PUB GraphicsDemo (same indention as k++):
waitcnt(clkfreq+cnt)

This updates the display only 1 time every second. Enough time for a photo...

Andy

File Attachment :
TSD_GraphicsDriver.spin 24KB (application/octet-stream)

This file has been downloaded 85 time(s).

Eagleman
Registered Member

Date Joined Nov 2009
Total Posts : 22

Posted 12/17/2009 7:23 AM (GMT -7)

Ariba,

Here is the photo of your TSD_Graphics_Demo on my 4.3" LCD. Hope this is good enough.

Also attached is a photo of one of Ray's TFT LCDs in a Serpac 15-S-A box from Mouser.

Post Edited (Eagleman) : 12/17/2009 2:44:30 PM GMT

Image Attachment :

Box_LCD43.JPG 193KB (image/pjpeg)

This image has been viewed 81 time(s).

Image Attachment :

LCD_Graphics.jpg 136KB (image/pjpeg)

This image has been viewed 78 time(s).

M.E.S.H
Registered Member

Date Joined Dec 2009
Total Posts : 13

Posted 12/17/2009 9:00 AM (GMT -7)

I was just wondering what kind of case that would fit the lcd !

Would be nice to get a metal front-plate to this lcd (witch actually keeps the lcd in place behind it as well). As thin as possible (of course not in the nano level of thin just because it's possible

), so that the lcd's edges are click-friendly (with a finger-tip), even in the corners. Also some fixing points in that plate so that different back-ends could be used (45 degree uptilted table/kiosk mini stand, Ariba - the Pocket/PDA Prop, a Wall-mounted etc.)..

Nice to see the photos w installations (and even more graphics drivers

/M.E.S.H

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