It is very easy to interface an MCU with a character LCD (let say, 16x2, 20x2, 20x4, etc.) because we don't need to constantly refresh what is displayed. Once we send what we want to see, it is displayed as long as the LCD is powered.
On the other hand, if we want to use a, let say, 800x600 graphics LCD (TFT or whatever with Parallel RGB interface) with the same MCU, we need to refresh the whole frame at a specific frequency, which almost make it impossible to use such an LCD with a relatively slow MCUs whose clock speed is, say, 16MHz or 20Mhz. Even if we choose a faster MCU, the display refreshing process takes most of its processing power.
Taking into account that, I am not going to display a video stream on the LCD, rather than that, I just would like to use the LCD as the information panel of a machine like a CNC machine where most of the things on the display will be constant and only some parameters will change;
- Do I still need refresh entire frame continuously?
- Is there a simpler way to overcome this without using FPGA, PLA, etc?