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9 years, 3 months ago.
TFT LCD Display
Hi Motoo
Your program to develop a simple oscilloscope looks good! Currently i am working on a project to try to develop a low cost oscilloscope and i would to ask for your permission for your program. And i would like to ask you for help if i meet any problem as i am new to this Mbed and i would like to know how do u do to achieve the above program
I have the MIKROE-495 DISPLAY PROTOBOARD, TFT 320X240 , would this work with this using the correct library? Thanks
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1 Answer
9 years, 3 months ago.
Dear Wei-san,
Thank you for your having interest in my sample program.
As you can see, I have already "published" it,
you should be able to use the program any way you'd like to use
as far as it follows the "Apache license."
I have the MIKROE-495 DISPLAY PROTOBOARD, TFT 320X240 ,
would this work with this using the correct library?
For the screen resolution it should be ok, I don't know if it has touch sensing or not.
Since my program utilize touch sensing for menu selection and trigger setting,
if the board does not have touch sensing, you must provide some user interface to do the work.
And i would like to ask you for help if i meet any problem
as i am new to this Mbed and i would like to know
how do u do to achieve the above program
If it can fit in my "budget" of free time, I'm happy to.
moto
HI Motoo-san Do you have circuit diagram for the board to the ada fruit 2.8 " TFT LCD display I like to know how is the board connected and connected to which pin for the KL25Z and the LCD display for the LCD to work as i myself got the adafruit TFT LCD
posted by 28 Feb 2015Hi, Wei-san,
You can download the circuit from
https://learn.adafruit.com/adafruit-2-8-tft-touch-shield-v2/downloads
moto
posted by 28 Feb 2015Hi motoo-San is it possible to achieve this oscilloscope by using one kl25z board or I need more than one kl25z board to achieve for the LCD display and the oscilloscope. Is it possible to do with only the adafruit TFT screen.
posted by 28 Feb 2015Hi, Wei-san,
The two kl25z were used for input signals.
Please refer to my funcgen program for that.
So you can achieve the oscilloscope with only one FRDM-KL25Z and adafruit TFT.
If you have a FRDM-KL25Z and an adafruit, why don't you import the program and give it a try?
moto
posted by 28 Feb 2015Hi Moto-san, does that mean that the input signal will be probe for my oscilloscope and the kl25z will be able to power up my Adafruit LCD Dsiplay.Does that mean that the KL25Z is my power source to power up my adafruit LCD. Is it possible to achieve the oscilloscope if i do not connect my adafruit LCD to my KL25z. Can i connect my adafruit LCD display and my kl25z seperately Thanks Wei
posted by 01 Mar 2015Hi, Wei-san,
Have you read the schematics of Adafruit and FRDM-KL25Z
as well as the source code?
Anyway, the oscilloscope takes two analog inputs
A0(PTB0) for channel 1 and A1(PTB1) for channel 2
So I used a couple of FRDM-KL25Z with funcgen to generate
two different signals for input channels of the oscilloscope.
Does that mean that the KL25Z is my power source to power up my adafruit LCD.
Yes, when connected to FRDM-KL25Z, the LCD's power source is FRDM-KL25Z.
Is it possible to achieve the oscilloscope if i do not connect my adafruit LCD to my KL25z.
Assuming the SPI signals and gnd are intact it should work,
but needless to say, you must provide power to the LCD by yourself.
Can i connect my adafruit LCD display and my kl25z seperately
You can connect anything to anywhere, as far as you know what you are doing.
moto
posted by 01 Mar 2015Hi Moto-san , May i know what is the highest frequency and voltage can this oscilloscope withstand as i am trying to hook up. Afraid that my frequency and voltage will be too high and damage the board.
posted by 02 Mar 2015Hi, Wei-san,
May i know what is the highest frequency and voltage can this oscilloscope withstand as i am trying to hook up.
For the voltage, I would think 0V to 3.28V (max)
For the frequency, you can connect any frequency,
but because of sampling freq of 20us, around 20KHz would be max.
To reasonablly view the wave, I would recommend 5KHz or less.
You know, this oscilloscope is using ADC of FRDM-KL25Z.
moto
posted by 02 Mar 2015Hi Moto-san, I have trided the oscilloscope and is able to work, after that i try to connect the function generator that you provide to LCD it is able to work but after some time the TFT adafruit is unable to work for the touch screen is unable to work. is there anything to do to rework LCD touch screen
posted by 05 Mar 2015Dear Wei-san,
Since the program was my first trial and I have not done
any product level stress test, there may (must) be some bugs.
Having said that, so far what I have noticed is that the touch is not
very responsible when the oscilloscope is in running mode.
Would you try
(1) stop the oscilloscope
(2) set the value or other settings
(3) start the oscilloscope
May be I have to implement this sequence in TSC detect routine.
moto
P.S. Anyway, I'm happy hearing that it worked when you tried ;-)
Hi moto- San I was unable to use the touchscreen as it is not responsive unable to press stop but it still manage to show sin wave tri wave and sqt wave on the channel just that it was unable to stop and trigger to other mode
posted by 05 Mar 2015Hi Wei-san,
I've run my FRDM-KL25Z more than 10mins, but TSC still worked.
May be there is/are other trigger for the problem.
Would you let me know how to reproduce the symptom?
moto
is there any possibility that my TSC is faulty, the time division maintain at 300us when even i restarted or reset my TSC
posted by 06 Mar 2015Hi, Wei-san,
After my previous post, I ran it over an hour, but still could not reproduce the problem.
At your site, how log will it take for the TSC to freeze? //
Meantime, from what are you providing power to the FRDM-KL25Z
and the Adafruit TFT with touch?
May be the power supply is not enough.
My case, I'm using MacBook Pro 13",
which can provide 1A+ from its USB port,
it may make difference.
is there any possibility that my TSC is faulty,
At this point I can not tell.
BTW, after each reset, does it work again?
the time division maintain at 300us
when even i restarted or reset my TSC
This seems to be normal, my program is not keeping track of last time division.
Meantime, can you Zoom Out and Zoom In?
If you can both the program and TFT/TSC seem to be OK.
moto
posted by 06 Mar 2015Hi Moto-san, i was unable to zoom in and out , after each reset, it is still unable to work. Do you have any email that i can send to to demo my problem to you Thanks
posted by 07 Mar 2015Hi Wei-san,
May be you can create a team here and let me join,
so that semi-private info can be handled.
moto
Hi Wei-san,
From what you wrote, TFT seems to be working, but TSC does not.
To make the TSC work, you must connect PIN_CS_TSC,
which is PTA13 of FRDM-KL25Z and D8 of Arduino Shield,
would you check if it's connected right?
Meantime, to test the behavior of TSC, you can use my test program
test_SPI_STMPE610
http://developer.mbed.org/users/Rhyme/code/test_SPI_STMPE610/
If touched position values are printed in the terminal screen,
the TSC (and STMPE610) is working, otherwise I suspect that
there are some HW problem in your system.
moto
posted by 07 Mar 2015Hi Moto san , i have tested that my TSC is able to work maybe some problem with HW, but now manage to work for TSC. Hi Moto, how does the trigger mode Rise fall level mode and how does the trigger marker move. unable to make the trigger marker and mode work
posted by 08 Mar 2015Hi, Wei-san,
Lots of questions (lol)
Anyway, I'm glad hearing that your TSC is working.
Do i need to connect two channel for the Oscilloscope to work
No, actually without connecting any, it should work,
I don't know if we should call it "work", though."
how does the trigger mode Rise fall level mode and how does the trigger marker move.
Just touch the point you'd like to set trigger on the TFT.
I recommend to stop oscilloscope when you set trigger level.
And see if the arrow marks point where you'd like to have the trigger.
Sometimes it points somewhere else accidentally ;-P
moto
BTW, Wei-san,
I'm just curious, but have you ever read my oscilloscope's page?
http://developer.mbed.org/users/Rhyme/code/oscilloscope/
I wonder if my English usage description is that bad... orz
moto