RESOLVED - Unable to run Atmega328P on breadboard alone (without programmer)

Using Arduino Microcontrollers
1

Hi,

I want to run an atmega328p on a breadboard with a ftdi adapter on a 14.7456mhz clock (to have 921600 stable serial communication) and I have an issue.

I downloaded the library 'minicore' which include a lot of custom clock compatible for the Atmega328P.

What I succefully manage to :
-I can burn a bootloader using another arduino as isp
-I can burn the sketch using another arduino as isp

My current issue :
After I've burnt the bootloader+sktech to the Atmega328P using the programmer, I disconnect the programmer from the computer and plug the ftdi adapter of the breadboard to power up the project as normal.
I dont manage to get any serial commucation if the arduino programmer is unplugged from the isp port.
If the arduino programmer is still wired on the isp port, I manage to communicate on baudrate 115200 only.

Do someone ever had issue similar to this ? My breadboard atmega328p doesnt works if the programmer is unplugged from the breadboard

My current wiring :
-I have a 10k ohm pull-up resistor on the reset
-I dont have anything wired to Aref and Avcc

My current board settings :
Board type : Atmega328
Bootloader : Yes/No (tried both)
Variant: 328P / 328PA
BOD : tried all BOD included disabled
Clock : 14.7456mhz
LTO : disabled (also tried enabled)

2

bouletmarc:
After I've burnt the bootloader+sktech to the Atmega328P using the programmer...

  1. All in one or sketch after bootloader? Sketch after the bootloader - the bootloader has been removed.
  2. Did you compile the bootloader for your clock speed?
3

  1. it only work all in one (if its really what you want to say) I cannot upload any sketch at all using the ftdi, I can only upload using a programmer, I burn the bootloader and then 'upload sketch using programmer'

  2. yes obviously

4

RESOLVED

actually I wasnt unplugging fully the arduino programmer from the breadboard, I was only unplugging the 5V wire from the isp and letting all other isp wires still wired and that caused the issue, when I unplug all 6x isp wire after the sketch as been uploaded with the programmer it works perfectly on baudrate 921600

I had fixed that bug already a long time ago, but in the time that my real pcb get received to test on real board, I felt again in that issue and getting worried that I never took note of how I fixed it earlier, i'll maybe glue all 6x isp wire together so all 6x always gonna be removed at once, I might never lead to that issue again since im not using a 2x3 header, but individual wires

5

Congrats.