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SINT022ATFT Issues: Reset, Rotation, and Drawing

I have brought this display which I am happy with so far apart from a few issues.

This was to be used on a few of my projects:
1: Amateur Radio Unit (main project)
This was to be the display unit for the whole radio and the demo image was what made me choose this display.

2: Hand held game (side project)
This was to be a little side project to get use to the display and to have fun writing little games etc, but power usage was an issue.

3: Various Test Equipment.
For custom equipment like Frequency Counters and Spectrum Analyzer etc.

Now for my issues so far...
1: It seems to draw more current that I hoped and what the spec says.
I think 240mA is rather a lot and this along with other devices like the low power AF Amp and PIC MCU it all mounts up and due to this one of my little side projects had to stop due to this.

2: For the life of me I just cannot get my PIC MCU to handle the LCD Rest/Initialization.
Granted when the LCD handles the Auto Initialize its all fine, but when I reset teh PIC MCU its just doesn't initialize.

3: I had issues at first with back to front displaying like the image below: 

But ended up using Cmd 0x22h and setting bit 4 which sorted it out.

4: I am trying to get the display to rotate so that I have 320x240 layout but it doesn't seem to go right:
This is what I want:

But I get the following (notice the bit on the left):

Ok, now the main issues are out of the way, I have one more small issue...

I know we can create Lines, Squares, Circles which can also be filled, but how do we do slanted squares like the following:

I am basically trying to display a filter layout, the red and blue lines should be fine (3 lines each) but the filled orange shape I have the issue with.
Also the red and blue lines move side ways also changing the width of the orange shape.

So is there a way to do this without having to draw pixel by pixel.

Also how do I clear the display without getting that annoying flicker.
I am displaying stuff when they need to be updated which has worked so far, but suppose I display a message box etc how would I remove that from the display without the need to re-display the whole display again.

Apart from that I am rather please with the display.


dtechsupport's picture
November 19, 2012

Regarding your reset issue, it sounds like an issue with the reset pin of the INT board. Please make sure that when the PIC resets that the reset pin on the INT board is not allowed to fall. We generally use a pullup resistor on the reset pin.
For the rotation, you'll want to use the registers:
DPCR: To set the rotation and memory write direction
HDWR: To set the horizontal resolution
VDHR0 and VDHR1: To set the vertical resolution.
As for the polygons, unfortunately you will need to do these manually. You can achieve this by drawing a series of rectangles of varying size. This will be more efficient than the pixel-by-pixel method.
Regarding "flicker" and message boxes, there is no way to re-draw an area of the screen without having that area stored somewhere in memory. If you display a pop-up dialog over an image, you should be able to just redraw the image in the area that you used. If however, you have multiple widgets or text or boxes etc, you will need to redraw the entire screen. Another option might be to store the entire frame buffer in a secondary frame buffer in another area of memory (if you have that available) and read from that secondary buffer to redraw only one part of the screen. For the 2.2"@16bpp, this will require an additional 150kB of memory.