Arduino zero No serial monitor.

Hello I'm having a hard time getting a serial montor from D21 chip. I'm programming it using the SWD pins on the arduino zero board. I can program with out no problem. But i can not get a simple Hello world Serial monitor or something like a analog pin read.

I'm just using the example sketches that come with the Arduino ide. i can do a hello world example if it's local to the board and it outputs it to serial monitor. But when i pass it through the SWD pins to the D21 chip i get nothing.

I have a white oled 128x64 screen i can bring up just fine with a hello world or push buttons but not a Serial monitor. Can someone please help me. I been searching online for the past 2 days and i get nothing.

Joseph

According to the schematic, I can’t see a separate chip handling the USB-TTL conversion, so I am assuming that the USB is handled natively by the D21 chip. Is it possible that when you use the SWD pins, you overwrite the firmware for the USB, therefore kill your serial monitor?

Hello Perehama to be honest i have no clue. This is still new to me. I'm sorry i forgot to tell this in the first post. I have two zero boards one is Modified by taking out two resistors bypassing the D21 chip on the original board and just making it as a programmer only. I found a site a while back that explains that. However i can not seem to find that site again. And when it does that it lets me use the SWD pins the 10 pins on the back of the zero board as a programmer to program a blank D21 chip. The second zero board is unmodified so i can compare it to the blank chip and see if it is working or not. I can program it the blank chip with no problems. I just can't do Serial monitoring.

Joseph

Hopefully, someone else can weigh in on this, but my comment is just my suspicion. There are 2 USB ports described in the documentation, and 3 serial ports, one of which is typicall TTL and could work with any MAX232 or similar chip, or FDTI chip etc. Make sure you are printing to the right port, and make sure you have the right COM port selected in the serial monitor.

Hello that might be the problem. I didn't know there was three serial monitoring's? How can i try the other two then the one I'm currently using?

Joseph

Hello just a update i did find this.

Also found this too.

https://learn.adafruit.com/using-atsamd21-sercom-to-add-more-spi-i2c-serial-ports?view=all

Joseph

josephchrzempiec:
I'm programming it using the SWD pins on the arduino zero board.

Are you using the Arduino IDE to do this?

Hello Pert yes I’m using the lateest IDE.

Edit: Update i have tired everything. I still can not figure out what I’m doing wrong or why i can not get a Serial monitor.

Which “board type” do you have set, and which serial port of the d21 are you using (and how?)
Just the swd pins will not support a serial monitor.

Hello from what I'm reading you are correct. The SWD doesn't support Serial monitoring. It also stats that it uses I2c Serial monitoring from the arduino zero programming chip and because that is not there i can not use it. So i have actually figure out something. Sense i don't have Serial monitoring but i do have I2C broken out. I do have a i2C screen a 20x4 display I'm going to program that as my serial monitoring.

you can use native USB for Serial Monitor even if you upload over programmer

Hello Juraj sense it is on a new board now i can not break out the Native USB to program or serial monitor. AT the time of ordering theses boards it was my mistake there. I didn't design these boards it is what i found online and didn't ask if they i an add native USB programming. I can bodge wire them in. But it be a bad looking hack job. So for now I'm working on adding a i2C lcd for a Serial monitor.

josephchrzempiec:
Hello Juraj sense it is on a new board now i can not break out the Native USB to program or serial monitor. AT the time of ordering theses boards it was my mistake there. I didn't design these boards it is what i found online and didn't ask if they i an add native USB programming. I can bodge wire them in. But it be a bad looking hack job. So for now I'm working on adding a i2C lcd for a Serial monitor.

Is it not an Arduino Zero?

It is a Zero bootloader and a D21 chip same as the zero board.

so what board is it? do you have a link or schematics?

A guy i talk to online build this 4 months ago and i never haven't heard from him sense then. No Schematic's only just the broke out pins. I'll talk pictures later on.

In theory, I think you can reconfigure the same pins used for swd to run a UART instead. You wouldn’t be able to use them for debugging at the same time, and it would be relatively “advanced” programming (not supported by the arduino core by default.)

Hello Westfw. What i did i followed HumanHarddrive on youtube he has a video on arduino to arduino i2c serial communication here. and i was able to get Serial monitoring to work.

you have to go 15:22 minutes into it to see the one i have used.