LCD control over FlexIO

[eyalbarzilay]

The K82 manual describes a possible implementation of LCD control with a parallel interface (such as the Intel 8080 or Motorola 68K) over FlexIO. Does anyone know of an actual software implementation which I can reuse? Specifically I am looking into connecting a SSD1289 LCD to a FRDM-K82F board but I'll take anything similar. Thanks.

[eyalbarzilay]

BTW I ended up implementing this LCD driver last October using FlexIO (calling low level driver from the Kinetis SDK). It worked just fine. Turned out my LCD controller was SSD1298 (not 89) but they are all similar. FlexIO is a bit complicated (only because it has A LOT of options) but I figured it out for the most part.

Eyal

[rqbh]

Hi Eyal,

Whick bus  you are using?  the 8080 bus or RGB port ?

the 8080 bus is already in the new SDK driver.

[eyalbarzilay]

Hi Kevin,

I used the 8080 bus. My LCD controller (SSD1298) offered 8080 or 6800 buses, which are quite similar to each. I think I could use both. The example in the FlexIO chapter of the K82 manual (60.5.9: Motorola 68K/Intel 8080 Bus Interface) was quite helpful.

[xiangjun_rong]

Hi,

I attach an application note an5280.pdf which addresses the topic using flexIO to drive LCD based on K82.

Hope it can help you

BR

Xiangjun Rong

[eyalbarzilay]

Thank you, Xiangjun. I have looked into this app note. It seems like this implementation directly controls the LCD and also manages the frame buffer. I am looking into interfacing with a LCD controller such as the SSD1289 using a parallel interface (Intel *080 style or Motorola 68K style). This type of implementation is explained in section 60.5.9 of the K82 reference manual. It uses FlexIO as well but the interface is different. Also in my case the frame buffer is inside the LCD controller.

Thanks for your response,anyway!

Eyal

[xiangjun_rong]

Hi, Eyal,

If you use the SSD1289, I just browsed the data sheet of the SSD1289, I do NOT think you can use flexIO to interface with SSD1289 for logic interface.  Fortunately, I think  you can use FlexBus to interface with SSD1289 with Parallel 8080 Timing Characteristics.

BR

Xiangjun Rong

[rqbh]

Hi xiangjun,

Why the SDK2.2 flexio drivers did not include the RGB interface LCD driver ?

[xiangjun_rong]

Hi, Kevin,

The FlexIO module is mainly used to simulate/extend the serial port for example uart, spi, SAI, IIC, so we do not develop the examples for parallel communication in SDK, you have to develop yourself.

sorry for not helping you.

BR

Xiangjun Rong

[eyalbarzilay]

Hi Xiangjun,

Thanks for looking into this. But why do you think I can't use FlexIO to communicate with SSD1289? What is the specific reason? Note again that the NXP K82 manual explains how to communicate with smart LCD controllers such as the SSD1289 using FlexIO PLUS 3 GPIO pins. It's explained in section 60.5.9 of the K82 manual. Here is a quote from the manual:

"The Motorola 68K and Intel 8080 bus are two parallel interfaces commonly used by Smart/Asynchronous LCD controllers. In conjunction with GPIO, FlexIO is able to drive these interfaces using one Timer and one Shifter, although additional Shifters could be used to support large transfers via the DMA controller."

Then the K82 manual also gives the details of how to configure the FlexIO for this purpose.

Do you think the NXP K82 manual is wrong? Please explain why?

Thanks again!

Regards,

Eyal

[xiangjun_rong]

Hi, Eyal,

I am sorry, you are right that you can use FlexIO to write the SSD1289, I just consider the FlexIO as a serial flip-flop.

sorry.

BR

XiangJun Rong