Graphic LCD display module design advice

Hi All,

I’m embarking into realms unknown on a design project and I’d appreciate some advice to help me choose the proper path. After some time I’ve finally found an LCD that I’d really like to use in a project, a CrystalFontz CFAX12864T-TFH. This is a 128 x 64 graphic LCD with LED backlight which uses a Novatek NT7534 controller capable of 8-bit Parallel or SPI communication. I’d like to interface it to a PIC microcontroller programmed with PBP. There will also be an Intersema MS5541 pressure sensor in the mix.

Minimum I/O needed with SPI:

1 PMW: LCD Back light
1 Digital: In Push Button
5 Analog: Sensors
ICSDAT: In Circuit Serial Programming
ICSCLK: In Circuit Serial Programming

SPI MCLK: Intersema MS5541 pressure sensor (and LCD ?).
SPI SCLK: Intersema MS5541 pressure sensor (and LCD ?).
SPI Din: Intersema MS5541 pressure sensor (and LCD ?).
SPI Dout: Intersema MS5541 pressure sensor (and LCD ?).

Since the MS5541 doesn’t have a CS pin I’d have to add a 3-state buffer to isolate the Dout if I also used SPI to talk to the LCD display.

2 Digital outs: Chip Selects

I guess my first question is whether I should use SPI or 8-bit Parallel to talk to the LCD graphic display module? There won’t be any fast screen changes, maybe updates every ½ second. I don’t have a grasp for the amount of time it would take to do a total screen refresh if I used SPI versus 8-bit parallel.

If I use 8-bit parallel and program in PBP ….. just how do I go about doing that? PBP LCDxxx commands are designed to be used with Hitachi 44780 controller, not the Novatek NT7534 controller on the CrystalFontz display. Would I have to develop my own module to handle the timing etc ?

I did buy the CFA-10021 demo board to play around with the display before I decided if it was what I wanted to use. There’s C code available on the CrystalFontz web site for the demo board that uses an Atmea2561 micro, I’m starting to look at it, but I’m not a C programmer ……

Any assistance in pushing me in the right direction would be greatly appreciated,
Mark