Unfortunately, i tried to take a photo about the wiring but it is not clear since there are too many wires.
I'm using a perfboards, so all the wire are soldered.
However, i tried to connect and re-connect the display to my arduino several times and all the time connections are ok but there are strange characters on the display.
The most important thing is that when I run the diagnostic sketch, I'm able to see the triangle which is under all the strange characters and the black pixel lines.
As you can see in the previous photos, sometimes the correct characters are in background since strange characters and black lines are foreground.
avrio is at the very lowest level. That is not the point that would be modified.The upper layer routines in gText and glcd call routines in glcd_DeviceIt is the glcd_Device class that talks across the h/w interface using functionslike ReadData() and WriteData(), SetDot(), SetPixels(), etc...Even those functions don't call avrio routines directly. They use wrapper macros defined in glcd_io.h to hide the low level i/o and to deal withwith the control line mappings in the panel configuration files.To change the h/w interface, you need to slice it at either the glcd_Device layeror replace the glcd_io macros.I'd recommend altering the glcd_io macros to match what ever hardwareyou are looking at implementing.From a hardware perspective the biggest challenge if trying to multiplex pins ishow to deal with the bi-directional needs. i.e. the data has to read as well as written.You can turn on the GLCD_READ_CACHE option which will eliminate the data reads at the expense of using up SRAM, but that doesn't completely solve the need for readsin that the code will still need read access to the BUSY status which requiresreading data bit 7.
So it looks like I'm going to have to use a graphics display and handle all of that myself (which I'm not looking forward to).
Before I go to the trouble of buying a display, wiring it without an i2c (again not looking forward to that) can someone please verify for me that the GLCD will let me to display text easily with some of the words inverted?
And although this may not be the place to ask, does anyone know of a text display that will do what I want so that I don't have to go the route of a graphics display?
[this is hightlighted] this is not
I did not think about reading. Ultimately I need 3 pins for the shift register to arduino I suppose.Perhaps I can reduce CS1/CS2/RW/RS/E/RST down to 3 and leave the 8 data pins alone? Not as big saving, 6 to 3 as opposed to 8 to 3, but still better than nothing? Means glcd would need 12 pins.I'm guessing a Uno is not fast enough to do this serially?
Having never used a graphics display (only text so far) is it necessary for the normal day-to-day use of a graphics LCD to be able to read back the data? I know many times on text displays in order to simplify things we just tie the RW pin to ground and only write. If I'm not writing some sort of game with sprites and I'm just using it to draw graphs or or display text and bitmaps do I ever need to read from a graphics display?Thinking about this in terms of simplifying the wiring.