LCDInfo.com

I understand the LCD-00569 (nokia 128x128 lcd) uses spi, and that the exact protocol for commanding it to draw is different depending on the controller/driver that the lcd comes with
(
epson controller: http://www.sparkfun.com/datasheets/LCD/ ... 493_03.pdf
Philips 132 x 132 x 3 PCF8833 http://www.nxp.com/acrobat_download/dat ... 8833_1.pdf
)

and the non-knockoff, LCD-00763 (Graphic 128x128 OLED) uses the spi-based SSD1339 driver... the Inex Graphic LCD 84x48 uses yet another spi based controller (Philips PCD8544)...

In general, are these spi protocols somewhat close, or would swapping lcds be a complete re-write of the software?

The reason I ask is that I have a board with software (that I didn't write) that drives via spi, an RiT 14201 series LCD (model RGS13128096WH000) (SSD1329U2 driver?)...
unfortunately, I can't get a hold of the lcd's datasheet, I just know that it's spi based. Since the board/software already does all the graphics drawing, I'm hoping to drop a replacement lcd whose protocol is similar so that the software changes are minimal.

Any suggestions?

You may still do some minor changes, but the 3-line SPI with D/C control bit should be similiar, the changes may related to the organization of Display RAMs.

Have you tried anything?