Arduino Uno & uBlox max-7 using hardware serial

Projects General Guidance
1

I'm creating a tracking board for a project and need the GPS module to use the hardware serial ports 1 and 0 on the Arduino Uno.

If I use the GPS module with software serial ports on the Arduino then I get timing issues and the manufacturer recommend using the hardware serial.

I have connected it in the following way:

uBlox max-7 TX Port -> 1K Resistor -> Arduino Port 1 (TX)
uBlox max-7 RX Port -> 1K Resistor -> Arduino Port 0 (RX)

I believe the resistors are there so that I can still program the Arduino but this doesn't seem to work though and I have to unplug the prototype board to be able to program it?

I think I may just add a second serial port and use that for debugging which would allow me to remove the resistors entirely.

2

There's already resistors between USB/Serial chip and D1/D0 so that external devices can access the pins. But yes, you must disconnect to program from PC because the USB/Serial chip cannot then overcome the external device.

Most GPS have fairly slow IO speeds, software serial should be sufficient to receive data.
The output is 0/5V level? (and not RS232?)

3

#include <SoftwareSerial.h>
SoftwareSerial mySerial(4,5);

4

Silver89:
but simply changing that to:

SoftwareSerial ss(0, 1);

Does not work?

Must say I haven't tried it, perhaps it works when you don't use any standard (hardware) serial commands.

But, why would you use pins 0 and 1 for softwareserial-purposes ?
Both are part of your hardware serial port and can be used with standard serial commands.

5

uBlox max-7 TX Port -> 1K Resistor -> Arduino Port 1 (TX)
uBlox max-7 RX Port -> 1K Resistor -> Arduino Port 0 (RX)

On my uBlox-6 it is the other way around. GPS-TX -> Arduino-RX, etc. Here is an example of using software serial with a uBlox Neo 6M: Arduino Your Home & Environment: Arduino & uBlox Neo 6M GPS

Edit: If the module gets stuck in an unusable mode (manufacturer's binary protocol, baud rate wrong, etc.) you can download the "u-center" control program and reset the module to factory settings (or anything else you want) u-center. You will need a laptop or desktop running Windoze and a USB-TTL serial adapter to communicate with the module.