Solved: U8G2 ST7586 performance question

sphilips · August 3, 2019, 10:52am

Hello!

I have somewhat slow performance with my display.
I include a link to YouTube that shows it. Now this is a rather large bitmap that it renders. However, the performance is equally slow when just displaying text. You can see it render from top to bottom.

Ive tried with a standard Uno and a STM32 maple, and the performance is similiar. This leads me to believe that it is either the LCD itself, or my configuration of it.

Please see this code, (the bitmap is not completely included here since the forum wont let in all those characters) Just for demonstration purposes.

#include <U8g2lib.h>



U8G2_ST7586S_ERC240160_1_4W_SW_SPI u8g2(U8G2_R0, 13, 11, 10, 9, 8);

#define u8g_logo_width 240
#define u8g_logo_height 160
static unsigned char u8g_logo_bits[] = {
 
  0x00, 0x00, 0xE0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x07, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0xF0, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0x0F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0x1F, 0x00, 0x00, 0x00, 0x00, 
  0x00, 0x00, 0xF0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x0F, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0xF8, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xE0, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0x0F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0x1F, 0x00, 0x00, 0x00, 0x00, 
  0x00, 0x00, 0xF0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x0F, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0xF8, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0x1F, 0x00, 0x00, 0x00, 0x00, 
  0x00, 0x00, 0xE0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x0F, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0xF0, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0x0F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0x1F, 0x00, 0x00, 0x00, 0x00, 
  0x00, 0x00, 0xF0, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0x0F, 0x00, 0x00, 
  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 
  0xF8, 0x1F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF0, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFB, 0xFE, 0xFF, 0xFB, 0xFE, 0xFB, 0xFE, 
  0x7F, 0xFF, 0xFF, 0xFB, 0xFE, 0xFF, 0xFF, 0xFF, 0xFB, 0xFE, 0xFB, 0xFE, 
  0xFF, 0xFB, 0xFB, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
  0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 

  };



void setup() {
  // put your setup code here, to run once:
u8g2.begin();
}

void loop() {
  // put your main code here, to run repeatedly:
  u8g2.firstPage();
    do {
    
          u8g2.drawXBM( 0, 0, u8g_logo_width, u8g_logo_height, u8g_logo_bits);
             
        
      } while ( u8g2.nextPage() );

  
    delay(100);
}

Any ideas?

david_prentice · August 3, 2019, 11:58am

Hardware constructors will always give better performance.
Your display is 240x160. So a Uno can only be used in 1 or 2 buffer mode. e.g.

//U8G2_ST7586S_ERC240160_1_4W_HW_SPI(rotation, cs, dc [, reset])  240 bytes
//U8G2_ST7586S_ERC240160_2_4W_HW_SPI(rotation, cs, dc [, reset])  480 bytes
//U8G2_ST7586S_ERC240160_F_4W_HW_SPI(rotation, cs, dc [, reset])  4800 bytes
U8G2_ST7586S_ERC240160_2_4W_HW_SPI u8g2(U8G2_R0, 10, 9, 8);

For a STM32 you can afford to use the F buffer.

I would expect the Uno to give you a reasonable performance with your "big" display. An 128x64 SSD1306 is 1/5 the size but it works fast with HW SPI.

David.

sphilips · August 4, 2019, 3:14pm

Thank you very much for your reply.

Im not sure what circuit changes a HW constructor will need though?

david_prentice · August 4, 2019, 3:47pm

There are no wiring changes for HW. You have already chosen the correct HW pins for a Uno.

STM32 is a different matter. If you are using the weird Maple Core or the official Core from STMicroelectronics.

SW or HW is a no-brainer. HW is always going to be faster but it means you must use the HW MOSI and HW SCK pins.
SW is designed for punters that choose random pins.

David.

sphilips · August 5, 2019, 5:46pm

Thank you!

Tested this out, and wow it is great now!

Its as instant now. Really glad to get that sorted out.
Its even hard to see any "lag" when uploading a complete bitmap to it.

Granted, this is with the STM32 though, will be interesting to see if the Uno/Nano is much of a difference.

system · May 6, 2021, 4:02am