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EK-TM4C123GXL: Basic LCD Screen Recommendation?

Part Number: EK-TM4C123GXL

Hi, can anyone recommend a basic LCD screen that works well (and relatively easily) with the TM4C development board?  I have the Kentec QVGA Display BoosterPack but it's overkill for what I want (and uses up all my GPIO pins).  I'm wanting something like a Hitachi HD44780 LCD controller but that operates using SPI.  Any suggestions or mentions of past experiences of success from others would be very much appreciated.  Thanks. 

  • Love your paying (proper) homage to the "grandfather" of (most) character based Lcd Modules.    (HD44780 - although HD43160 was an even earlier version.     "43160" - just as Sony's "Beta" - lost the "marketing war" to a (lesser) standard "44780" "VHS" ...)

    There are 144x32 pixel display modules - which accept both 4/8 bit data bus - as well as (near) SPI data input.      (serial clocked data - thus 2 wire, write-only)     These modules employ the ST7920 Lcd Controller - are less available/more costly  - you should read/review the ST7920 spec "IF" (near) SPI is a "real" requirement...)     Module is the same size as "standard" 2x16 Lcd.

    These 144x32 modules are FULL, Pixel-Graphic capable - as well as "backwards compatible" w/"existing" 4 or 8 bit, Character Modules hw & sw!     As such - they provide a very unique means to, "Add interest to otherwise "boring/mundane" text-only displays" (via the use of Graphics) - while maintaining the past code investment in text modules...

    More available - and SPI based - are multiple OLED (full graphic) modules.     Of course (unknown) is your definition of "basic" & "relatively" easily...

    Certain of these are available w/"High Contrast" Lcd fluid - I've attached a photo for your review...    (note the "solder-less" test connector)

  • In reply to cb1_mobile:

    Hi, thanks for the reply.  Yeah, that was what I was going to go for.  Looking around a bit though, and thinking more about my use case (and possible use cases I'm not even currently aware of) I think I'm going to go with something a little bit more robust like this:

  • In reply to Terence D:

    Terence D
    I'm going to go with something a little bit more robust

    Having quickly looked at the specs for (that) display - (your/my definition) of "robust" appears (very) far apart!       And - no attempt to justify that "claim of robustness" appeared.

    Following may reduce (any) such claims of robustness:

    • that display has a non-standard pinout "pitch" - forcing the design of a pcb or "tack solder" to each of those (non-standard) 19 pins!
    • that display is FAR from your desired "SPI interface!"     It requires an EXTRA input signal (A0) - along with "normal" SPI clock & data.    You (may) be able to tie A0 to a spare GPIO - and then "remember" to set/clear it - based upon data vs. command.     (maybe)  
    • that display requires the installation of TEN discrete capacitors to support (multiple) "charge pumps" - almost surely forcing the design of a custom pcb.
    • that display provides (only) a 32x8mm "Active Area" (pixel field) - far smaller than that earlier suggested.
    • that display has lower contrast AND a very (limited) Viewing Angle far less than that earlier suggested.
    • and - that display has fewer pixels.

    You (may) have (other) reasons for choosing that display - but "robustness" seems (difficult) to justify.      Words have meaning - do they not?

    For your benefit - & interested others (in support of my comments) - here appear 2 "key" extracts from "that display's" data sheet:

    Note: TEN added capacitors AND the "Creation" of a  (SECOND)  SPI Data Signal (A0) - Complicating (or disallowing) any claim to,  "SPI" - and  no (known) connector!

    Now comes the (SPI Challenged) interface timing diagram:

    It (may) be possible to "bit-bang" (non-standard/unwanted) signal A0.     (timing edges appear to be met when supplied by "bit A0" - introduced (prior) to the "call to SPI transmit."

  • In reply to cb1_mobile:

    Hi, thanks for pointing all of this out.  Clearly it shows my lack of experience with displays.  I have experience with various chip peripherals but have not done anything with displays before.  It's pretty clear now that I should take a step back and start with something more basic and recommended.  

    Looking back at your first reply to my question, I believe the picture you've posted is very similar to this:

    I've reviewed the datasheet and it seems fairly straightforward.  If my understanding is correct, I'll need to use a total of 9 GPIO pins on the TM4C to interface with the display.  I count this as 8 for DB0-DB7 and then one for RS.  I'm not crazy about using about having to use that many pins but in light of all of the difficulties you pointed out with the other display I mentioned, this appears to be a small price to pay.

  • In reply to Terence D:

    First & foremost - so neat to see you respond so well to the (suggested) course correction. Firm/I have (some) slight experience w/displays (20+ years) - thus (usually) may provide (some) insight...

    Now heavily involved in "Autonomous Auto" - and have big meeting - will read/review your new "find" & comment when it ends. (if it ever does...)

    Your attitude guarantees that you are (very) coachable - that's the first thing we seek when "hiring and/or advancing!"

    Assume that you are in "Euro-land" - might you name several close/favored distributors - so staff here can check.     (I'm in San Jose, CA - at least for today)

  • In reply to cb1_mobile:

    My 08:30 meeting "held off" till 08:45 - thus I've learned you (likely) are in/around Poland.    

    The "disty" you found stocks the following, Graphic LCD, "DEM 122032A SBH-PW-N"- which I believe (more suitable) for you.     (and I will (try to) assist you over (most all) "rough spots.")     (if any)     This is a 122x32, Graphic LCD - w/white Led backlight & parallel interface.

    Note that this too (like the one I showed) is a "Negative Transmissive" type Lcd - which yield the greatest Contrast & "Visual Appeal."      (Pity that this disty had not purchased my firm's "Solder-less, Spring-Loaded Connector - so that the Display's Pixels (quickly & w/out (any) disty effort) could, "GLOW INSTANTLY to LIFE!")

    Do download & review the specs - by my (very) fast read - no "tormenting" capacitors - nor "absence of connector" - arrive w/this display.

    The flexibility of Graphics will prove "Much to your benefit" - even though - and especially though - you will "curse me" during development.     End results count!

  • In reply to cb1_mobile:

    Hi, cb1_mobile, thanks for the reply. Apologies for the misunderstanding about my location, I'm actually in the states. I came across that distributor simply by using Google search (for images) and using the image in your original post. The first search result returned was to the link in my previous post to It didn't even occur to me at the time that was a non-US distributor. I usually use distributors like Mouser, Jameco and DigiKey.

    When also searching using your image I happened to come across this previous thread:

    Before posting this current thread (i.e. my original post here) I did search the forum for past conversations about using displays but unfortunately did not find this thread at the time. It appears it will be quite helpful for me as I get into to writing code to output to the display.

    I am not able to find the "DEM 122032A SBH-PW-N" display you recommend at any of my usual distributors or seemingly any distributor in the states for that matter. Could you possibly recommend one from a US distributor?
  • In reply to Terence D:

    In the (now) immortal words of one Bartholomew Simpson, "Ay Caramba!"       Google images giveth - and (too often) taketh away...

    I'm on a flight to the midwest shortly - will have something for you by early tomorrow (Sat) - at the latest...

    Never would I have thought that a US guy would provide the spec of a (small) "Polish" disty!    (seems pretty accomplished disty - I must add)

    While there are NO kidz in San Jose (almost none) this forum has (nearly) closed prior to 12:30 PST, today.      That's not true of Silicon Valley - laptop action fast/furious around me - "early shut-down" ain't happening here...

  • In reply to cb1_mobile:

    As promised - arrives now - my (considered) Display recommendation for you: "NHD-14432WG-ATFH-V#T-ND."      Item is "in stock" - priced @ 16.50 (USD) @ Q=1, Digikey.

    This is a 144x32 (graphic capable) Lcd module - but is (uniquely) able to operate (initially) under "Stealth Mode!"     (i.e. performs as a (standard) Lcd Character Module - using "known" hardware & software)        

    To my mind - this provides the "best of two worlds for you:"

    • Character Mode gets you "up/running" quickly - and with (reasonable) ease
    • Later - you may employ this same display & introduce "Pixel Graphics" - which opens a new world of capability!     (while avoiding "holding you hostage" to demanding graphic coding - to achieve (even) the most basic, "first pixel for display!")       (indeed - you are welcome)

    You may use much (perhaps all) of the earlier post's "code & direction" - which I generated for that (past) poster.

    Later - when you're ready - we can "venture into Graphics" - unlocking the (real) value & uniqueness of that display.

    Note that the display listed is w/out the unique, "High Contrast Lcd fluid" and "Wake the Dead" (BRIGHT!) Led Backlight - (both unique to my firm - yet we sell in volume (only).)

    You should now be, "On your way."      Might you "honor" the effort put forth here - and "Verify Answer" (one or more of these postings)?       Merci.

    It would be of extreme interest to note if any "Polish" forum users may be inspired enough to "try" the earlier Graphic display I found/noted - resident @ the Polish disty...

  • In reply to cb1_mobile:

    cb1_mobile - You are my HERO!!!  I can't say thank you enough for your help!


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