Interfacing to multiple serial devices?

Forum 2005-2010 (read only) Hardware Interfacing
1

Hello, first time on the Arduino so please bear with me.

I am attempting a project in which I would like to interface with:

  1. an XPort - to grab time via NTP from nist.gov (like the 3 Meter project)
  2. a Maxim DS1306 Real Time Clock - to store the time received by the Xport and provide interrupts to the Arduino to write the time to a
  3. Maxim 7219 to display the time form the RTC on six 7-segment LED displays.

I'm trying to graft this project together from three separate projects, each using the above components, however I'm running into a little trouble understanding how to set up the code to communicate with all three. For instance, all three projects use serial.begin, but different speeds. Is there a (relatively) simple way to do this? Two software serials and a hardware serial?

Thanks! ;D

2

This is not really posible. And then again .-)

Arduino only has one "real" serial port and the serial protocol is a point to poibt protocol, meaning you cant daisy chain devices on the serial port.

You can however use the soft serial libary to implement a software serial port on any two digital pins you choose.

I don't know if you can have more than one instance of the soft serial running at the same time, but i guess its possible.

Check the playground for soft serial sample code.

3

Hi,

I am attempting a project in which I would like to interface with:

  1. an XPort - to grab time via NTP from nist.gov (like the 3 Meter project)
  2. a Maxim DS1306 Real Time Clock - to store the time received by the Xport and provide interrupts to the Arduino to write the time to a
  3. Maxim 7129 to display the time form the RTC on six 7-segment LED displays.

I have no idea how to interface from the arduino to he XPort, but the DS1306 does not use or need a Serial-line, it is driven via SPI

which something completely different.

I guess the MAX7229 was a typo, and you meant a MAX7219?
The 7219 also uses SPI and there is already some information how to drive 7-segment LED-Displays with it :
http://www.arduino.cc/playground/Main/LedControl
So the serial-line is free for the xport to use.

Eberhard

4

Why didn't i see that :slight_smile:

5

Why didn't i see that :slight_smile:

Monday morning? (at least here 500km east of the Prime Meridian)

6

Of course! Now it makes more sense. And I believe the Xport uses a software serial, so even with all three I'm still not using the hardware serial. I think where I got confused were the multiple serial.begin() commands, but on closer inspection, it looks like all three projects were using the hardware serial to spit results out to a computer... I guess I don't need multiple serial.begin commands afterall. Thanks!