Microchip Explorer 16/32 with PIC24 -> SSD1963 driver board -> 320 x 240 Newhaven TFT display

ezed413 · August 12, 2019, 2:19pm

Hello all. I want to use LittlevGL with a 320x240 Newhaven Graphic display driven with a SSD1963 driven from a Microchip Explorer 16/32 development board with a PIC24. Is there an example on how to set the driver up to do this? Thanks in advance.

kisvegabor · August 13, 2019, 1:43pm

Hi,

As in initial reference you can take a look at this driver.

You need to fill these defines with the appropriate pins and register writes/reads:

github.com

littlevgl/lv_drivers/blob/4923dd010f9e16f3bbaf147dca8a86655512a0bd/lv_drv_conf_templ.h#L28-L49


/*------------
 *  Common
 *------------*/
#define LV_DRV_DISP_INCLUDE         <stdint.h>           /*Dummy include by default*/
#define LV_DRV_DISP_CMD_DATA(val)  /*pin_x_set(val)*/    /*Set the command/data pin to 'val'*/
#define LV_DRV_DISP_RST(val)       /*pin_x_set(val)*/    /*Set the reset pin to 'val'*/


/*---------
 *  SPI
 *---------*/
#define LV_DRV_DISP_SPI_CS(val)          /*spi_cs_set(val)*/     /*Set the SPI's Chip select to 'val'*/
#define LV_DRV_DISP_SPI_WR_BYTE(data)    /*spi_wr(data)*/        /*Write a byte the SPI bus*/
#define LV_DRV_DISP_SPI_WR_ARRAY(adr, n) /*spi_wr_mem(adr, n)*/  /*Write 'n' bytes to SPI bus from 'adr'*/


/*------------------
 *  Parallel port
 *-----------------*/
#define LV_DRV_DISP_PAR_CS(val)          /*par_cs_set(val)*/   /*Set the Parallel port's Chip select to 'val'*/
#define LV_DRV_DISP_PAR_SLOW             /*par_slow()*/        /*Set low speed on the parallel port*/
#define LV_DRV_DISP_PAR_FAST             /*par_fast()*/        /*Set high speed on the parallel port*/

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ezed413 · August 19, 2019, 4:11pm

Kisvegabor,

I was wondering if you can list your pic32 driver example. I’m a Little confused about the LV_DRV_DISP_PAR_SLOW/FAST macro’s. The code should be pretty much the same as the PIC24. We are thinking of using LittlevGL in the next generation of our product. Thanks.

Ed

kisvegabor · August 20, 2019, 8:03pm

Unfortunately, I can’t share the real drivers because they were part of a proprietary development.

These are used to set a low or a higher clock speed on the parallel port. It might be required because SSD1963 can’t communicate too fast until its PLL is set. I suggest selecting a quite low (~1MHz) clock for first to see if the display is working and try to increase it.

barbiani · September 11, 2019, 2:38am

Hello everybody,

I just got a pic32mx@80Mhz and the ssd1963 running the demos and I would like ask what kind of frame rates and user experience are you getting with this controller?

It works fine but looks like the first svga cards to appear in the market.

Second step will be trying DMA and dual buffers.

Thank you.

kisvegabor · September 11, 2019, 4:30am

I used PIC32MX695F512H with a 480x320 TFT via a 16 bit parallel port (used PORTB to manually write data) and got about 10-20 FPS.

Using DMA to flush in the background will approximately double the FPS
Turn on optimization (-O1 is free). It’s also a huge speed up.