RE: ST7735 gfx demo ?

Øyvind — Thu, 10 Dec 2020 08:05:05 GMT

Hello,

What version of the nRF5 SDK are you using? You need to look in the datasheet of the display to find the function of each pin.

If this is a SPI device, remember that SS (Slave Select) = CS (Chip Select). I don't know what RS, RES or DC do. Searching DevZone, I found the following thread which might be of interest: https://devzone.nordicsemi.com/f/nordic-q-a/53165/gfx-example-not-working-with-st7735-lcd.

From examples\peripheral\gfx\pca10040\blank\config\sdk_config.h (nRF5 SDK v16.0.0) I found the following config settings:

// <e> ST7735_ENABLED - st7735 - ST7735R TFT controller
//==========================================================
#ifndef ST7735_ENABLED
#define ST7735_ENABLED 1
#endif
// <h> SPI_CONFIGURATION - SPI configuration

// <o> ST7735_SCK_PIN - Pin number  <0-47> 


#ifndef ST7735_SCK_PIN
#define ST7735_SCK_PIN 25
#endif

// <o> ST7735_MISO_PIN - Pin number  <0-47> 


#ifndef ST7735_MISO_PIN
#define ST7735_MISO_PIN 24
#endif

// <o> ST7735_MOSI_PIN - Pin number  <0-47> 


#ifndef ST7735_MOSI_PIN
#define ST7735_MOSI_PIN 23
#endif

// <o> ST7735_SS_PIN - Pin number  <0-47> 


#ifndef ST7735_SS_PIN
#define ST7735_SS_PIN 22
#endif

// <o> ST7735_IRQ_PRIORITY  - Interrupt priority
 

// <i> Priorities 0,2 (nRF51) and 0,1,4,5 (nRF52) are reserved for SoftDevice
// <0=> 0 (highest) 
// <1=> 1 
// <2=> 2 
// <3=> 3 
// <4=> 4 
// <5=> 5 
// <6=> 6 
// <7=> 7 

#ifndef ST7735_IRQ_PRIORITY
#define ST7735_IRQ_PRIORITY 6
#endif

// </h> 
//==========================================================

// <o> ST7735_SPI_INSTANCE
 
// <0=> 0 
// <1=> 1 
// <2=> 2 

#ifndef ST7735_SPI_INSTANCE
#define ST7735_SPI_INSTANCE 0
#endif

// <o> ST7735_TAB_COLOR  - Color of the tab attached to the screen.
 
// <0=> INITR_GREENTAB 
// <1=> INITR_REDTAB 
// <2=> INITR_BLACKTAB 
// <3=> INITR_144GREENTAB 

#ifndef ST7735_TAB_COLOR
#define ST7735_TAB_COLOR 0
#endif

// <o> ST7735_DC_PIN - Pin number  <0-47> 


#ifndef ST7735_DC_PIN
#define ST7735_DC_PIN 19
#endif

// <o> ST7735_HEIGHT - ST7735 height  <0-162> 


#ifndef ST7735_HEIGHT
#define ST7735_HEIGHT 160
#endif

// <o> ST7735_WIDTH - ST7735 width  <0-132> 


#ifndef ST7735_WIDTH
#define ST7735_WIDTH 128
#endif

// </e>

// </h> 
//==========================================================

I also recommend looking at the drivers of the ST7735:
components\drivers_ext\st7735\st7735.c

The API reference in our Infocenter: https://infocenter.nordicsemi.com/topic/sdk_nrf5_v16.0.0/group__st7735__config.html

When you have connected correctly, have a loot at the GFX Library sample.

Kind regards,
Øyvind

RE: ST7735 gfx demo ?

RixtronixLAB — Thu, 10 Dec 2020 03:59:47 GMT

How to wire this LCD ?

Where can I connect RES, RS ?

It has ST7735 chipset but I'm not sure on how to wire it with sdk_config.h

// <o> ST7735_SCK_PIN - Pin number <0-47>

#ifndef ST7735_SCK_PIN
#define ST7735_SCK_PIN 47
#endif

// <o> ST7735_MISO_PIN - Pin number <0-47>

#ifndef ST7735_MISO_PIN
#define ST7735_MISO_PIN 46
#endif

// <o> ST7735_MOSI_PIN - Pin number <0-47>

#ifndef ST7735_MOSI_PIN
#define ST7735_MOSI_PIN 45
#endif

// <o> ST7735_SS_PIN - Pin number <0-47>

#ifndef ST7735_SS_PIN
#define ST7735_SS_PIN 44
#endif

// <o> ST7735_DC_PIN - Pin number <0-47>

#ifndef ST7735_DC_PIN
#define ST7735_DC_PIN 42
#endif

RE: ST7735 gfx demo ?

Øyvind — Wed, 09 Dec 2020 14:38:36 GMT

Hello,

I'm not sure this is the correct forum to ask. Have you read the manual of the display?

Kind regards,
Øyvind