9 years, 10 months ago.

Damaged Nucleo MCU?

Hello, I'm making my first steps with stm32 and mbed. I have (had) Nucleo F401RE board and TFT_320QVT module (with SSD1289). Unfortunately I connected LCD VCC to U5V, so SSD1289 might be damaged as it's operating on 3.3v. It was connected only for few seconds and nothing was getting hot so I hope it survived.

Pinout was like in code I used:

#include "mbed.h"
#include "ssd1289.h"
BusOut dataBus( PC_9, PB_8, PB_9, PA_5, PA_6, PA_7, PB_6, PC_7, PA_9, PA_8, PB_10, PB_4, PB_5, PB_3, PA_10, PA_2 ); 
SSD1289_LCD lcd( PC_6, PC_5, PA_12, PA_11, &dataBus ); CS, RESET, RS, WR
int main()
{
    lcd.Initialize();
    lcd.Print( "Hello, World!", CENTER, 25 ); 
       while ( 1 ) { }
}

Since then, also my Nucleo board stopped working. When I put new .bin file on it, it looks like binary is loaded but it's not executed. LED1(COM) and LED3(PWR) are on, but program is not executing (led blinking or pc.print).

1. How MCU could be damaged? Even if somewhere received from LCD 5v signal, it should handle it, I've read that Nucleo is 5v tolerant.

2. Or maybe it's not damaged, just blocked somehow (like Atmega with RESET pin reconfigured)?

Any ideas how could I check if MCU is damaged?