Need help using tm1637 on nRF528232 (SDK V15.2.0)

RE: Need help using tm1637 on nRF528232 (SDK V15.2.0)

MartinBL — Tue, 20 Nov 2018 13:23:59 GMT

Everything is relative I guess. I did a quick test with getItem's code and the Arduino library. With no extra limitations to the frequency (other than the slow nature of the bit banging itself) the clock frequency is 263 kHz:

Slow, but not slow enough. The nRF52 is a little too fast.

Test code:

#include <stdbool.h>
#include <stdint.h>

#include "nrf.h"
#include "nordic_common.h"
#include "boards.h"

#define Clkpin 22
#define Datapin 23

#ifndef INPUT
#define INPUT 0x00
#endif

#ifndef OUTPUT
#define OUTPUT 0x01
#endif

#ifndef INPUT_PULLUP
#define INPUT_PULLUP 0x02
#endif

#ifndef HIGH
#define HIGH 0x01
#endif

#ifndef LOW
#define LOW 0x00
#endif

void pinMode (uint32_t pin, uint8_t mode)
{
  if (mode == OUTPUT)
  {
    nrf_gpio_cfg_output (pin);
  }

  else if (mode == INPUT)
  {
    nrf_gpio_cfg_input (pin, GPIO_PIN_CNF_PULL_Pulldown);
  }

  else if (mode == INPUT_PULLUP)
  {
    nrf_gpio_cfg_input (pin, GPIO_PIN_CNF_PULL_Pullup);
  }
}

void digitalWrite (uint32_t pin, uint32_t value)
{
  nrf_gpio_pin_write (pin, value);
}

uint32_t digitalRead (uint32_t pin)
{
  return nrf_gpio_pin_read (pin);
}

void writeByte(int8_t wr_data)
{
  uint8_t i,count1;   
  for(i=0;i<8;i++)        //sent 8bit data
  {
    digitalWrite(Clkpin,LOW);      
    if(wr_data & 0x01)digitalWrite(Datapin,HIGH);//LSB first
    else digitalWrite(Datapin,LOW);
    wr_data >>= 1;      
    digitalWrite(Clkpin,HIGH);
      
  }  
}

/**
 * @brief Function for application main entry.
 */
int main(void)
{
    pinMode(Clkpin,OUTPUT);
    pinMode(Datapin,OUTPUT);
    writeByte(0xAA);
    while (true)
    {
        // Do nothing.
    }
}
/** @} */

RE: Need help using tm1637 on nRF528232 (SDK V15.2.0)

awneil — Tue, 20 Nov 2018 12:57:41 GMT

[quote userid="3500" url="~/f/nordic-q-a/40694/need-help-using-tm1637-on-nrf528232-sdk-v15-2-0/158171"]I don't see anything in the Arduino library that limits the frequency[/quote][quote userid="75287" url="~/f/nordic-q-a/40694/need-help-using-tm1637-on-nrf528232-sdk-v15-2-0"]the code uses pinMode, digitalWrite, and digitalRead[/quote]

I think that would severely limit the speed (ie, frequency) ... ?!

RE: Need help using tm1637 on nRF528232 (SDK V15.2.0)

MartinBL — Tue, 20 Nov 2018 12:50:31 GMT

I don't see anything obviously wrong in your code. It could be a timing issue though. This datasheet states that:

And I don't see anything in the Arduino library that limits the frequency. You should probably do as awneil suggests, and verify that your nRF52 outputs correct signals.

RE: Need help using tm1637 on nRF528232 (SDK V15.2.0)

awneil — Tue, 20 Nov 2018 11:08:47 GMT

Have you checked the specifications of that display, and verified that your code is generating the correct signals as required?

How to properly post source code: