The Arduino Pro Mini 328 - 5V/16MHz is with a price tag of $2-$10 very cheap but it has no USB connection to program it.
With a FTDI FT232RL USB to TTL Serial Converter Adapter Module where the pin has a lay-out of DRT - Rx - Tx - VCC - CTS - GND the program can be loaded without any soldering.
Attach the FDTI module as shown, select Arduino Nano as board in the Arduino
IDE and upload a program to the Pro mini.
In this example we wil program a TM1640 16-digit display.
#include <TM1638.h> //
required because the way arduino deals with libraries
#include <TM1640.h>
TM1640 module(0, 1); // connect Data to pin 0 and SCLK to Pin 1
void setup()
{
// nothing to do here
}
void loop()
{
char text[17];
int n;
int uur, minuut;
long msec;
uur = (int)(millis()/3600000);
minuut = (int) (millis()/60000)%60;
msec = millis();
n = sprintf(text, "%0.3d %0.2d %9ld" ,
uur, minuut, msec);
module.setDisplayToString(text);
}
Ed Nieuwenhuys Nov 2018