Raspberry Pi doesn't see Mega

I am trying to connect a Mega to my rpi to use the serial monitor to troubleshoot the code. I program it on my PC, which works fine. Unfortunately the PC is 10 feet away from where the pi and arduino are, so I can.t use it.A Uno didn't show either. I program it on the PC because the rpi is too slow.

Jim

Do you have Arduino IDE installed on RPi?

saravananm92:
Do you have Arduino IDE installed on RPi?

Yes I do.
I'm trying to use the serial monitor through Arduino.

Jim

You are lacking very much on detail.
How are you connecting the two together.
What is connected to the Mega to view the serial monitor on?

Grumpy_Mike:
You are lacking very much on detail.
How are you connecting the two together.
What is connected to the Mega to view the serial monitor on?

The USB input on the Arduino is connected to a USB port on the pI through a powered USB Hub.
A VGA monitor is connected to the Pi through a VGA/HDMI adapter and I want to use the Serial monster provided by the Arduino program on the Pi, at least that is what I hope to do. In the meanwhile I am using Arduino on a PC not in sight and going back and forth on my wheelchaiir. What a hassle that is! I have successfully connected the Pi to the Arduino via I2C and am attempting to control hardware on the Arduino with the Pi and need to see what the Arduino is doing.

Jim

I think I can help you if you give some more information:

I understand that you want to control your Arduino Mega using RPi, But I didn't get what you wish to achive by using the Serial monitor.

have successfully connected the Pi to the Arduino via I2C and am attempting to control hardware on the Arduino with the Pi

Have you removed the I2C from blacklist of bcm2835?
Are you trying to control your arduino by I2Cfirmata protocol?

The USB input on the Arduino is connected to a USB port on the pI through a powered USB Hub.

I have found that using this method the Arduino can appear at one of two com port addresses at random.
In python I cope with this as so:-

import serial
try:
   ser = serial.Serial('/dev/ttyACM0',115200, timeout=2)
except :
   ser = serial.Serial('/dev/ttyACM1',115200, timeout=2)

Grumpy_Mike:

The USB input on the Arduino is connected to a USB port on the pI through a powered USB Hub.

I have found that using this method the Arduino can appear at one of two com port addresses at random.
In python I cope with this as so:-

import serial

try:
   ser = serial.Serial('/dev/ttyACM0',115200, timeout=2)
except :
   ser = serial.Serial('/dev/ttyACM1',115200, timeout=2)

I don't understand why everyone is so fixated on what I doing. Think of it this way, i loaded the Arduino software, plugged in the Mega, and there is no listings in "Tools>Serial Port". so I cannot even download code, much less use the serial monitor to monitor what the Arduino is doing! The i2c is working fine, the blacklist is correct! I can blink the port 13 led from the pi just fine!

Jim

Sorry if I sounded irritating, I was confused by the I2C and serial monitor , dumb me :slight_smile:

Are you plugging the Arduino directly to the USB Port in RPi, if yes then try using a powered USB hub(it may happen that the RPi cannot provide sufficient power to the Arduino through USB).

If it didn't worked try booting RPi with Arduino connected.

If that too didn't work,sorry I don't have anymore ideas. I don't have Arduino and ,I only have a Arduino on beadboard with CP2102 for USB TTL conversion and it seems RPi detects it and I am perfectly ok with using arduino with RPi.(Since RPi uses a linux distribution it must detect FTDI/atmega too , I don't know).

saravananm92:
Sorry if I sounded irritating, I was confused by the I2C and serial monitor , dumb me :slight_smile:

No problem, I just saw that I needed to reduce things.

Are you plugging the Arduino directly to the USB Port in RPi, if yes then try using a powered USB hub(it may happen that the RPi cannot provide sufficient power to the Arduino through USB).

I am connected to the rpi through a powered USB 3.0/2.0 hub.

If it didn't worked try booting RPi with Arduino connected.

Good suggestion, but no joy, the Tools>Serial Port menu item is still grayed out
If that too didn't work,sorry I don't have anymore ideas. I don't have Arduino and ,I only have a Arduino on beadboard with CP2102 for USB TTL conversion and it seems RPi detects it and I am perfectly ok with using arduino with RPi.(Since RPi uses a linux distribution it must detect FTDI/atmega too , I don't know).

I am now connecting a 20x4 lcd via the i2c bus to use as a serial monitor. I move the arduino over to the PC for programming and downloading. Still, a lot of hassle becuase of missing serial port! Where are the gurus?

Where are the gurus?

Well as this is actually a problem with the Raspberry Pi and not the Arduino you could try:-
http://www.raspberrypi.org/phpBB3/