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custom PCB and display for the Picasso-will this work?

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  • custom PCB and display for the Picasso-will this work?

    Hi! So, basically, I'm trying to design the final prototype of my device, but before I can do that, I need to be sure that I can create a PCB to make the Picasso SGC chip work with any display.

    Yes, I know, I should probably use your special development displays to make the prototype, but these are a little expensive, especially for a final product. I also want to learn how to make displays work with the chip. To begin with, I'm going to try and control this display:

    It looks compatible, all the pins match up. the only thing that doesn't is the touch screen, but I can control that via the main microcontroller.

    Besides everything looking OK, I want to be certain about a few things:
    1: I'm very confused about the DCENB (pin 49) on the chip. from the datasheet: "DC-DC high voltage enable signal. This maybe the high voltage thatdrives the LCD backlight or the OLED panel supply.High: Enable DC-DC converter.Low : Disable DC-DC converter."
    those last 2 lines and its name made it look like an input, but it's labeled output. I assume this goes to the backlight? Also, does this require a transistor or can it provide enough current? The backlight is also 3.3V, so I don't understand what this "high voltage" is about.

    2: is the audio amplifier circuit still required/different if you replace the speaker with a headphone jack? headphone speakers are tiny, PC speakers have built-in amplifiers and I have very little experience with audio circuits.

    3: The display supports 16 bit and 8 bit modes. I'm going to use 16 bit since that's probably faster (is it twice as slow, or does it limit it to only 8 bit colour? I think it's the first one), but would the display/controller get damaged if I accidentally switched it to 8 bit? They sell lots of displays, some are only 8 bit, and are pin compatible with all the others. however, those 8 bit models only use the upper 8 bits of the 16 bit bus, the lower ones (D0-D7) are not connected. would it be possible to use an 8 bit display with no hardware changes with this wiring? you would probably change something with the DISP tool, but I'm not sure if the upper 8 bits problem can be fixed trough software.

    4: is there anything special I need to change or set with the DISP tool? I know, 16 bit mode, resolution, things like that, but is there anything else? and would something get damaged if this is incorrectly configured?

    Sorry if that's a lot of questions, I'm just hoping it works first time, since I'm on a budget.