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Graphic LCDs / Any success with Newhaven Display LCDs?
« Last post by martinbaker2727 on November 20, 2018, 05:14:55 AM »
I have just ordered a Newhaven Display LCD
(Model number NHD-C24064WO-ATFH#-3V3 and I am a bit confused as to the purpose of the two data cables. I want to be able to control this with the Explorer 16 board however I am not sure where to start.
Will I have to write a driver for this LCD? Also, are the two ribbon cables controlling each half of the display? In this case, what would I have to add to the driver to accomplish this?

Any success (or even horror) stories are welcome. Thank you
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Graphic LCDs / C12864WC vs C12864LZ - Driving differences?
« Last post by bugfixin on November 18, 2018, 05:17:14 PM »
Hi, I have a couple of PCBs I've made with extremely similar circuitry, the only difference is in the pinout / connector for the display, a 30 pin flat flex for C12864WC (NHD-C12864WC-FSW-FBW-3V3-M) and a 28 pin 0.05" header for C12864LZ (NHD-C12864LZ-FSW-FBW-3V3-ND).

Both are using a 4x booster circuit with 1uF ceramic caps, resulting in approximately 12.8V on the vout terminal, with the same capacitance on v0-v4, driven via "4-wire" SPI with the same software using the same configuration values.

The C12864WC has MUCH lower contrast, to the point that it's almost invisible, while the C12864LZ works perfectly. The datasheets do not mention any real differences in software settings (at least not that I've seen), is there a significantly different value (electronic volume, etc?) i should be setting for one vs the other?
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TFTs / Re: NHD-2.4-240320CF-CTXI#-F Display Not Responding
« Last post by sjdorsay on November 18, 2018, 08:13:06 AM »
I finally have my display changing colours. However, the colours being displayed aren't the correct ones. For example when I send 0xF800 (Red) I get cyan. When I send 0x001F (blue) I get yellow. I am using the 8-bit parallel bus with 16 bpp (565 RGB). I will just treat it as a CMYK display.

For anyone who might have similar issues here is what I went through to get my display working.

Arduino:
1) 5V logic needed to be shifted down to 3.3V logic
2) Avoid using digital pins 0 and 1

Nucleo-F411RE:
1) Some of my jumper connections were not strong enough
2) Continue avoiding digital pins 0 and 1
3) Add delays after data bus is set to ignore cross talk interference
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OLEDs / Blinking Double Height Font NHD-0216CW
« Last post by MatthewKerr on November 13, 2018, 05:45:23 PM »
Hi.
I am using double height font with the NHD-0216CW. I would like to create a blinking effect by writing to DDRAM address 0x00 and 0x40 and switching between the two addresses. For example, i would write the following to each address:
0x00:  'Test:         On'
0x40:  'Test:           '

By switching between the two addresses, the right hand side of the display would appear to blink. This is to highlight to the user that the text 'On' is modifiable.
Currently I re-write to the display when I want the switch/blink to occur. But I suspect there is a better way to do this.
Thanks.
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OLEDs / Re: Double Height Font NHD-0216CW
« Last post by MatthewKerr on November 13, 2018, 05:38:14 PM »
Thanks Ted_M. That example has worked for me.
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TFTs / Re: NHD-2.4-240320CF-CTXI#-F Display Not Responding
« Last post by sjdorsay on November 10, 2018, 05:26:05 PM »
There were many issues with the schematic that I posted before which have been addressed and reflects the current implementation of my board (with the exception of the voltage translator).

I noticed that the Arduino uses 5V logic whereas the LCD requires 3.3V logic. This may have damaged the digital interface although I am not convinced this is the case. I ported the code onto an STM32F411RE on the NUCLEO-F411RE which uses 3.3V logic but there is no change to the behaviour.

I am thinking the issue is likely hardware base. A quick calculation using this calculator https://www.allaboutcircuits.com/tools/microstrip-crosstalk-calculator/ gives a cross-talk of about 1.14 V which may be enough to interfere with the interface.
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TFTs / Voltages and Power_Control registers with NHD-1.8-128160EF-CSXN#-F
« Last post by qfsasm on November 08, 2018, 12:38:44 PM »
Hi all!

We are using the NHD-1.8-128160EF-CSXN#-F in our design and we noticed a slight flickering that we did not see with the NHDev board. We believe that the flickering is caused by the different voltages of the power supply because we use 1.8 V for IOVDD and 2.6 V for VDD. On the NHDev board we measured 3.3 V for both.

The display is initialized with the same sequence as on page 10 in the datasheet. The commands for Power_Control are suspicious as they set the voltages for the TFT and they probably need to be adapted for our power supply. My question is if the parameter of the Power_Control should be changed when different voltages are used and if yes to which values? Also we will maybe change VDD to 2.8 V and in the next days we will install additional capacitors to make the power supply more stable.
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TFTs / Re: Difficulty with SPI with NHD-4.3-480272FT-CSXV-CTP
« Last post by Ted_M on November 08, 2018, 10:07:16 AM »
Hi Makoto.inoue,

It's good to hear you have solved this issue.

Thanks for posting the solution!

Best Regards,
9
TFTs / Re: Difficulty with SPI with NHD-4.3-480272FT-CSXV-CTP
« Last post by makoto.inoue on November 07, 2018, 08:00:22 PM »
Hi Ted,
Thank you for the response & suggestion.
I have solved my issue. 8)
The MCU(nRF52840) was not driving the SPI SCLK line enough (I think I was driving SCLK around 0.5mA).
I changed the MCU pin configuration to drive it higher (0.5mA --> 5mA) and now I’m receiving 0x7C properly. I presume FT813 needs somewhere near 5mA on SCLK to function…
10
Character LCDs / Problem with WHITE COLOR CHAR on NHD-0440WH-ATMI-JT with 2 lines
« Last post by Mic71 on November 04, 2018, 06:41:35 PM »
Dear ALL, I bought a LCD NHD-0440WH-ATMI-JT and I make the firmware on STM32 but I found a problem with WHITE color. This is my problem: when I enable two lines I not see the white color char but a blue with constrast loss . If disable two lines I see one line with WHITE color.... How I can see two lines with WHITE color char?

Thanks in advance

Michele

This my init code with TWO LINES.... Where I wrong?  :-\


     LCD_SetCommandPin4bit(0,0,1,1); // send 0011 : 0x30
     LCD_PulseEnable(iEx);
     DWT_Delay_us(5);

     LCD_SetCommandPin4bit(0,0,1,1); // re-send 0011 : 0x30
     LCD_PulseEnable(iEx);
     DWT_Delay_us(5);
 
     LCD_SetCommandPin4bit(0,0,1,1); // re-send 0011 : 0x30
     LCD_PulseEnable(iEx);
     DWT_Delay_us(5);
     
     LCD_SetCommandPin4bit(0,0,1,1); // ...setting 8 bit...
     LCD_PulseEnable(iEx);
     
     LCD_SetCommandPin8bit(0,0,1,1,1,0,0,0); // send 0011 1000 : 0x38 Function Set = 8bit mode; 2-line; 5x8
     LCD_PulseEnable(iEx);
     
     LCD_SetCommandPin8bit(0,0,0,0,1,0,0,0); // send 0000 1000 : 0x8 Turn off display
     LCD_PulseEnable(iEx);
   
     LCD_SetCommandPin8bit(0,0,0,0,1,1,1,1); // send 0000 1100 : 0xC Turn on display; cursor blink
     LCD_PulseEnable(iEx);

     LCD_SetCommandPin8bit(0,0,0,0,0,0,0,1); // send 0000 0001 : 0x1 Clear
     LCD_PulseEnable(iEx);

     LCD_SetCommandPin8bit(0,0,0,0,0,1,1,0); // send 0000 0110 : 0x6 Entry mode set
     LCD_PulseEnable(iEx);
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