Im trying to control the Arduino Multifunction Shield by using stm32l053r8t6. What is the coding for the 4-digits 7segment on the multi function shield?

[BTan.5]

Im only can display the 7segment by using "sortSegment (numbers);" and it only display at 4th 7segment. How can i select which 7segment i want to display, and how can i display Characters?

[gbm]

Check the schematics of your board - you will see the connections.

[Tesla DeLorean]

You have to shift in 4 digits

D8=data, D7=clk, D4=latch

[BTan.5]

this is the schematics of my Arduino Multifunction shield, and i just connect it to my stm32l053r8t6. Can someone teach me how to display my 7segment? Im already set the pin (PB5, PA8, PA9) to the gpio_output. Now i can only display numeric numbers, how to display characters?

[BTan.5]

Please teach me how to display characters and how to select which 7segment to display. Im already include the .c and .h files and i cannot understand it because im new to stm32:loudly_crying_face:

// this is .h file
#include "stm32l0xx_hal.h"
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
 
//=================================================================== I/O Pins AML
#define LOW 		GPIO_PIN_RESET
#define HIGH 		GPIO_PIN_SET
 
#define dataS(x)	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, x? HIGH:LOW)
#define shCLK(x) 	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_8, x? HIGH:LOW)
#define stCLK(x) 	HAL_GPIO_WritePin(GPIOB, GPIO_PIN_5, x? HIGH:LOW)
 
#define BUZ(x) 		HAL_GPIO_WritePin(GPIOB, GPIO_PIN_3 ,x? LOW:HIGH)
 
#define LED1(x) 	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_5,x? LOW:HIGH)
#define LED2(x) 	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_6,x? LOW:HIGH)
#define LED3(x) 	HAL_GPIO_WritePin(GPIOA, GPIO_PIN_7,x? LOW:HIGH)
#define LED4(x) 	HAL_GPIO_WritePin(GPIOB, GPIO_PIN_6,x? LOW:HIGH)
 
#define S1 			HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_1)
#define S2 			HAL_GPIO_ReadPin(GPIOA, GPIO_PIN_4)
#define S3 			HAL_GPIO_ReadPin(GPIOB, GPIO_PIN_0)
 
//=================================================================== Function Prototype
uint8_t getPB(void);
void LEDs(uint8_t decimal);
void displaySegment(void);
void multiplexSegment(uint16_t num4digit);
 
 

// this is the .c file
#include "praQdriver.h"
 
// Array data & variables used for 7-segment Common Anode - numeric value only
const uint8_t num[10] 	= {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90};
const uint8_t seg[4]	= {0xF1,0xF2,0xF4,0xF8};
uint16_t ptr2disp;
uint16_t buff[4];
 
 
uint8_t getPB(void)
{	uint8_t PBvalue=0;
 
	if(S1!=HIGH)	PBvalue |= 1<<0;
	if(S2!=HIGH)	PBvalue |= 1<<1;
	if(S3!=HIGH)	PBvalue |= 1<<2;
	return PBvalue;
}
void LEDs(uint8_t decimal)
{	LED1(decimal & 1<<0);
	LED2(decimal & 1<<1);
	LED3(decimal & 1<<2);
	LED4(decimal & 1<<3);
}
void displaySegment(void)
{	static uint8_t seg=0;
 
	stCLK(LOW);
	for(int8_t i=15;i>-1;i--)
	{	shCLK(LOW);
		if(buff[seg] & (1<<i))	dataS(HIGH);
		else					dataS(LOW);
		shCLK(HIGH);
	}
	stCLK(HIGH);
 
	if(++seg>3) seg=0;
}
void multiplexSegment(uint16_t num4digit)
{	for(uint8_t i=0;i<4;i++)
	{	switch(i)
		{	case 0:
				ptr2disp = num4digit / 1000;
				break;
			case 1:
				ptr2disp = (num4digit % 1000) / 100;
				break;
			case 2:
				ptr2disp = (num4digit % 100) / 10;
				break;
			case 3:
				ptr2disp = num4digit % 10;
				break;
		}
		buff[i] = (num[ptr2disp]<<8) | seg[i];
	}
}

[Tesla DeLorean]

But are the conceptual issues here STM32 related?

You've got a 16-bit shift register, one half is uses to select the digit to be selected, and the other half the 7-segments to illuminate.

You keep an MCU side buffer, and cycle thru the digits continuously, frequently enough for the scan/persistence to work.

Shift registers are a basic concept. You drive a bit, clock it into the chain, and then there's a latch to move the shifting register into a holding register.

Make sure you've properly initialized the GPIO pins.

If you have a scope or logic analyzer perhaps use those to confirm or review your understanding.