topic Re: LCD Displaying red, green, blue, white, black... in LPC Microcontrollers

LCD Displaying red, green, blue, white, black...

abderrezak — Thu, 21 Jul 2016 20:32:35 GMT

Hi All,

I was configuring the LCD peripheral on LPC1788, and for the first time I have such a beautiful strange result. My TFT start displaying a sequence composed from full screen unified color (red, green, blue, black, white) then a chessboard.

Please, help me to understand what this result correspond to?

Where this screen are stored on the RAM?

Thank you

Re: LCD Displaying red, green, blue, white, black...

Carlos_Mendoza — Thu, 28 Jul 2016 23:15:01 GMT

Hi abderrezak,

Could you tell us which example project are you using? Are you using a evaluation board?

Thanks in advance!

Best Regards,

Carlos Mendoza

Technical Support Engineer

Re: LCD Displaying red, green, blue, white, black...

abderrezak — Fri, 29 Jul 2016 10:18:17 GMT

Hi Mendoza,

Thank you for your replay

It's my own board. I have designed it starting from other open hardware board. It works well, I have no problème with it. Regarding the software, I use the LPCOpen 1.03 with the EA1788 example witch you found on the LPCXpresso.

I have this kind of strange issue when I tried to reconfigure the LCD to match with my own LCD. Now it work correctlly, but if I'm on debug, and I restart debugging, my LCD display the sequence I have described it the question.

Have a nice day :smileyhappy:

Thank you for your replay

Re: LCD Displaying red, green, blue, white, black...

abderrezak — Wed, 03 Aug 2016 10:04:08 GMT

Hi Carlos,

Do you have any explanation to my pseudo-issue

Thank you

Best regards

Re: LCD Displaying red, green, blue, white, black...

abderrezak — Thu, 04 Aug 2016 14:47:13 GMT

Hello,

To well describe my issue, I have made a video of the displaying sequence of the LCD

Dropbox - LCD issue.MOV

Thank you

Re: LCD Displaying red, green, blue, white, black...

Carlos_Mendoza — Fri, 05 Aug 2016 15:24:26 GMT

Hi abderrezak,

Thanks for the information.

Which is the sequence that you expected? Could you share your source code?

I didn't see anything abnormal in the video. If an issue do happen when debug session is restarted, a workaround is exiting debug session and then entering debug session again, so that debug entrance scripts (initialize SDRAM, etc) will run again.

Thanks in advance for your response!

Best Regards,

Carlos Mendoza

Technical Support Engineer

Re: LCD Displaying red, green, blue, white, black...

abderrezak — Mon, 02 Nov 2020 13:49:49 GMT

Hi Carlos,

Thank you for your interest in my issue.

The sequence I shared with you is the issue. I didn't expect any thing like this. I just initialized my LCD controller than I use it normally. This sequence appear when I restart debug. So each time I'm obliged to stop debug, reset my board than run debug again. I'm asking my self, where this shown sequence is stored?. Is it a sequence that the LPC1788 display when some issue occurs on the LCD Controller? I heaved searched everywhere an issue like this but without any result. So thank you again for helping me

About my source code, I start developing using the LPCOpen, the one you found with LPCXpresso. I have adopted the same software architecture of the EA1788 board because I like it. Of course I have modify the part like SDRAM & LCD in board.h&c.

const LCD_CONFIG_T RK043FN07H = { /* Rocktech Displays Limited */
     28,                              /* Horizontal back porch in clocks */
     10,                              /* Horizontal front porch in clocks */
     2,                              /* HSYNC pulse width in clocks */
     LCD_HEIGHT,                         /* Pixels per line */
     2,                              /* Vertical back porch in clocks */
     1,                              /* Vertical front porch in clocks */
     2,                              /* VSYNC pulse width in clocks */
     LCD_WIDTH,                         /* Lines per panel */
     0,                              /* Invert output enable, 1 = invert */
     0,                              /* Invert panel clock, 1 = invert */
     0,                              /* Invert HSYNC, 1 = invert */
     1,                              /* Invert VSYNC, 1 = invert */
     1,                              /* AC bias frequency in clocks (not used) */
     5,                              /* Maximum bits per pixel the display supports */
     LCD_TFT,                    /* LCD panel type */
     LCD_COLOR_FORMAT_BGR,     /* BGR or RGB */
     0          /* Dual panel, 1 = dual panel display */
};‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

STATIC const IP_EMC_DYN_CONFIG_T IS42S16160D_config = {

     EMC_NANOSECOND(64000000 / 4096),
     0x01,                    /* Command Delayed */
     3,                         /* tRP */
     7,                         /* tRAS */
     EMC_NANOSECOND(70),     /* tSREX */
     EMC_CLOCK(0x01),     /* tAPR */
     EMC_CLOCK(0x05),     /* tDAL */
     EMC_NANOSECOND(12),     /* tWR */
     EMC_NANOSECOND(60),     /* tRC */
     EMC_NANOSECOND(60),     /* tRFC */
     EMC_NANOSECOND(70),     /* tXSR */
     EMC_NANOSECOND(12),     /* tRRD */
     EMC_CLOCK(0x02),     /* tMRD */
     {
          {
               /* Base address */
               EMC_ADDRESS_DYCS0,

               /* RAS */
               3,

               /* Mode Register value */
               EMC_DYN_MODE_WBMODE_PROGRAMMED |
               EMC_DYN_MODE_OPMODE_STANDARD |
               EMC_DYN_MODE_CAS_3 |
               EMC_DYN_MODE_BURST_TYPE_SEQUENTIAL |
               EMC_DYN_MODE_BURST_LEN_4,

               /* Dynamic Configuration value */
               EMC_DYN_CONFIG_DATA_BUS_16 |
               EMC_DYN_CONFIG_SDRAM |
               EMC_DYN_CONFIG_16Mx16_4BANKS_13ROWS_9COLS |
               EMC_DYN_CONFIG_MD_SDRAM
          },
          {0, 0, 0, 0},
          {0, 0, 0, 0},
          {0, 0, 0, 0}
     }
};‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍

Best regards