RTOS/DK-TM4C129X: Interfacing TM4C129 microcontroller with a 5inch(diagonal) TFT screen

sunil swain said:

I understand that  TM4C129X board comes with a resistive lcd screen on board and tft screen is better than Resistive screen.

Terminology sometimes comes into play - does it not?      Your creation of the term, "Resistive Lcd Screen" is outside normal usage.    

Resistive is usually associated with the most basic form of Display Touch Screen - and is in "no way" confined to Lcd Displays.     (i.e. may be used w/OLED, Plasma, EL Displays)

TFT is one form of Lcd Screen - usually producing the highest Contrast and widest Viewing Angle.     (both highly sought & desirable)       Yet - your statement, "TFT screen is better than Resistive screen" places entirely different devices (apples vs oranges) into the comparison matrix.       Perhaps further investigation is required to boost your understanding.

Note that most all modern devices employ "Capacitive Touch Screens" which enable, "Multiple Touch Points & novel techniques such as "pinching" - both "beyond" the capability of Resistive Touch."

The "ease" of your objective has revealed - right here - just a few posting before yours:    https://e2e.ti.com/support/microcontrollers/tiva_arm/f/908/t/310347

Might your "investigation into Display & Touch" have been limited to those devices - just resident here?      Is that wise?       A broader search - seeking an MCU w/"real" Graphic Display Drive capability - and able to mate w/ the superior "Capacitive Touch" - may reveal more modern, higher performance, "Display-Touch" solutions...

Hello cb1,

I am new to this newheaven LCD. I have received a EK-TM4C1294XL launchpad board. Also i have a 5inch newheaven tft display  P/N: NHD-5.0-800480TF-ATXL#-CTP..

Please advise me the steps required to interface the board with the lcd.

Thanks and Regards,

 Sunil

sunil swain said:

I am new to this newheaven LCD.

My friend - any/all would "share" your "newness!"     (that firm is "Newhaven" - is it not?)

sunil swain said:

Please advise me the steps required to interface the board

Unstated is "why" you chose that particular display.    Would it not prove simpler/faster to choose a display which "best suits" your chosen MCU/board?     Forcing an MCU to comply w/a particular display proves - not always - "easy - nor quick!"

General, "How to interface a Display to an MCU" guide follows:

• Survey & record the "accommodation" the MCU makes for a display (if any)
• Survey & record the: Signal, Timing, & Voltage requirements of (any) candidate display
• Now determine the "degree of match" (i.e. compatibility) between the MCU and the display - especially as regards the 3 elements, listed just above
• The MCU must provide a sufficient number of output signals and be able to meet the "timing requirements" of the display.   There are methods by which you may increase the number of MCU output signals - the MCU's timing though is much more limited.   (i.e. this timing "must" meet (or must approach) the display's specification)

If you are "new" to this - you should know that certain displays contain, "Graphic Control ICs" - which significantly, "Speed, Ease, & Enhance" the "design-in" of such displays.    Displays without such Graphic Controllers impose HEAVY "Timing & Signal Requirements" (often even external memory requirements) upon your "MCU and "adjunct" components!    Often this proves a "too severe" demand for "new" users.

Your intended "volume of usage" greatly influences your "display & MCU" decision.    Most all (small) volume users should choose a display equipped w/on-board (or external) Graphic Controller.   (as this eliminates SO MUCH "pain/suffering!")    (both upon you & hapless helpers, here...)   

Most always some form of display backlight is furnished - and often requires a higher voltage than that (normal) for the MCU and related components.    You must provide for that - as well - matching both voltage & current requirements.    (you may be able to "PWM" the backlight electronics - which enables control of the backlight's brightness.)

You've "set to sea" with (some) storm clouds upon the horizon - gusting winds - is this voyage one you (really) want to launch?     Vendor here offers a "cruise ship" - with so much of the heavy sailing, "Done for you."   The display is smaller - pixels fewer - yet the course is "well-charted" - and your odds of "arrival" are greatly increased.    (i.e. there exists an "Add on board" (laughingly called "booster") which includes a QVGA display - possibly colored - firm/I have NO interest - you should check...)

Hello cb1, Thanks for the reply and helping me on the selection.

I searched and found that Kentec QVGA Display BoosterPack is compatible with Tm4c1294XL board. Please help me with the following answers and i will take a decision based on your reply.

1. I can't buy a Kentec QVGA Display BoosterPack, fit with my product as it is and sale it to customer. So what is the procedure if i want to fit the lcd within this boosterpack in my product.
2. If in future i want to upgrade the 3.5inch lcd that comes in boosterpack to 5inch lcd what change i have to make. will i have to look for another 5inch boosterpack again.

Regards,
Sunil

sunil swain said:

1. I can't buy a Kentec QVGA Display BoosterPack, fit with my product as it is and sale it to customer.

My friend - that's a statement - yet w/out explanation or justification.    Some here may have more experience in this focused field - your making such decision - absent their guidance - may not best serve your interest.

Do you seek to "camouflage" what you intend to produce - so that the client is "delayed" in their "discovery?"    (note that your helpers should NOT have to guess - eats time/effort - I'm on a plane in moments)

sunil swain said:

2. If in future i want to upgrade the 3.5inch lcd that comes in boosterpack to 5inch lcd what change i have to make. will i have to look for another 5inch boosterpack again.

Are you "locked into that specific 5" display?"   And if so - why is that?    Displays constantly upgrade & improve - deciding now may prevent a "better choice downsteam" (even a better display at lower cost) what then?

As to "what changes you must make" - was not the "point by point" guidance - given earlier - sufficient to START that process?   (I believe - staff believes - it was)   You write of "another 5" boosterpack."    I do not believe that this vendor is that advanced - just yet.    (same (now) old MCUs - what motivation exists to "upgrade a (claimed) booster pack"/(more properly) ADD-ON?

ARM MCUs - Displays - and their "marriage" are accomplished by many similar firms - some (already) feature superior displays - and the ARM MCUs include powerful, "Graphic Accelerators" making them far more accommodating of a variety of higher performance displays than those "Add Ons" (in no way "boosted") here...

Might your casting a "wider net" (i.e. broader based search) save us both - "time/effort?"

Hello Sunil and cb1,

As cb1 stated, his prior guidance of How to interface a Display to an MCU is as good a guide as any.

If you are new to LCD development, starting with the BoosterPack and using the TI examples offered via the DK-TM4C129X or using the Kectec BoosterPack with TivaWare example "ek-tm4c1294xl-boostxl-kentec-s1" would be a good place to start learning.

We also have a Graphics Library document you can reference in TivaWare "SW-TM4C-GRL-UG-2.1.4.178.pdf" which is under the 'docs' folder.

Interfacing a 5" screen is going to be a significant undertaking and shouldn't be underestimated. As cb1 also suggested, it might be best to find a screen with a built-in LCD controller/Graphics Control IC to simply the interface process if you are new to this realm.

Also I am not aware of plans to make a 5" LCD BoosterPack (though that doesn't mean it's impossible given I am not involved in the making of ANY BoosterPacks so...)

Anyways, I think either using the TI example or getting an LCD with an included graphics controller would be your best bets to start with.

Hi Ralph,

Appears that it is, "Poster's (uncharted) Way" or the "HighWay!"

There was an (almost) 4 month "gap" between poster's past and recent writings - "reality" often has unpleasant impact upon "less than well conceived/implemented" poster plans... (even w/"helper assistance" - espcially w/"helper assistance!")

As former US Defense Secretary Rumsfeld noted: "There are (both) "Known Unknowns" and "Unknown Unknowns"" - either are capable of "wreaking havoc" - poster may benefit from heeding our advice. (i.e. USE ONLY a Display w/Graphic Controller!)