Unable to get a reading from the GPS TinyShield. I've read the documentation for the GPS TinyShield as well as the notes from the TinyGPSPlus library. I have the TinyDuino board at the bottom, then the GPS TinyShield on top of the processor, and then the TinyShield USB & ICP board on top of the GPS.

I ran the Blink sketch successfully to ensure that everything was working properly. (From the IDE, the board I have selected is Arduino Pro or Pro Mini (3.3V, 8MHz) with ATmega328.)

To test the GPS, I used the setup from the example provided in the Tiny-Circuits site and then I used a simplified loop just to get some readings. However, I always seem to get the "No GPS detected" message. I also wasn't sure exactly which pin A0 or A1 is the RX pin on the GPS TinyShield - the example code has RX as A1 but the text above th example code on the Tiny-Circuits GPS tutorial states that RX is A0. I tried it both ways - same result.

I can't figure out why I am not getting any readings.

Code Select Expand

#include <TinyGPS++.h>
#include <SoftwareSerial.h>
/*
   This sample code demonstrates the normal use of a TinyGPS++ (TinyGPSPlus) object.
*/
static const int GPS_ONOFFPin = A3;
static const int GPS_SYSONPin = A2;
static const int GPS_RXPin = A0;
static const int GPS_TXPin = A1;
static const int GPSBaud = 9600;

// The TinyGPS++ object
TinyGPSPlus gps;

// The serial connection to the GPS device
SoftwareSerial ss(GPS_RXPin, GPS_TXPin);

void setup()
{
  Serial.begin(115200);
 
  // Init the GPS Module to wake mode
  pinMode(GPS_SYSONPin, INPUT);
  pinMode(GPS_ONOFFPin, OUTPUT);
  digitalWrite( GPS_ONOFFPin, LOW );   
  delay(5);
  if( digitalRead( GPS_SYSONPin ) == LOW )
  {
    // Need to wake the module
    digitalWrite( GPS_ONOFFPin, HIGH );
    delay(5);
    digitalWrite( GPS_ONOFFPin, LOW );     
  }

  ss.begin(GPSBaud);
}

void loop()
{
  while (ss.available())
    if (gps.encode(ss.read()))
    {
      Serial.print(F("Location: "));
      Serial.print(gps.location.lat(), 6);
      Serial.print(F(","));
      Serial.print(gps.location.lng(), 6);
    }
   
  if (millis() > 5000 && gps.charsProcessed() < 10)
  {
    Serial.println(F("No GPS detected: check wiring."));
    while(true);
  }
}

I am having the same issue

TinyGPS+++
Thank you for the well documented tutorial- I appreciate your time and help with all the examples but I can't seem to get this working as expected - I am using the TinyShield GPS with TinyDuino

DeviceExample.ino
A simple demonstration of TinyGPS++ with an attached GPS module
Testing TinyGPS++ library v. 0.92
by Mikal Hart

No GPS detected: check wiring.

An extensive example of many interesting TinyGPS++ features
Testing TinyGPS++ library v. 0.92
by Mikal Hart

Sats HDOP Latitude   Longitude   Fix  Date       Time     Date Alt    Course Speed Card  Distance Course Card  Chars Sentences Checksum
          (deg)      (deg)       Age                      Age  (m)    --- from GPS ----  ---- to London  ----  RX    RX        Fail
---------------------------------------------------------------------------------------------------------------------------------------
**** **** ********** *********** **** ********** ******** **** ****** ****** ***** ***   ******** ****** ***   0     0         0       
**** **** ********** *********** **** ********** ******** **** ****** ****** ***** ***   ******** ****** ***   15    0         0       
0    0    ********** *********** **** 05/26/2014 14:04:12 381  ****** ****** ***** ***   ******** ****** ***   339   0         0       
0    0    ********** *********** **** 05/26/2014 14:04:13 391  ****** ****** ***** ***   ******** ****** ***   643   0         0       
0    0    ********** *********** **** 05/26/2014 14:04:14 404  ****** ****** ***** ***   ******** ****** ***   947   0         0       
0    0    ********** *********** **** 05/26/2014 14:04:15 418  ****** ****** ***** ***   ******** ****** ***   1251  0         0       
0    0    ********** *********** **** 05/26/2014 14:04:16 428  ****** ****** ***** ***   ******** ****** ***   1555  0         0       
0    0    ********** *********** **** 05/26/2014 14:04:17 387  ****** ****** ***** ***   ******** ****** ***   1883  0         0       
0    0    ********** *********** **** 05/26/2014 14:04:18 399  ****** ****** ***** ***   ******** ****** ***   2211  0         0       
0    0    ********** *********** **** 05/26/2014 14:04:19 397  ****** ****** ***** ***   ******** ****** ***   2539  0         0       
0    0    ********** *********** **** 05/26/2014 14:04:20 418  ****** ****** ***** ***   ******** ****** ***   2867  0         0       
0    0    ********** *********** **** 05/26/2014 14:04:21 436  ****** ****** ***** ***   ******** ****** ***   3193  0         0       
0    0    ********** *********** **** 05/26/2014 14:04:22 448  ****** ****** ***** ***   ******** ****** ***   3519  0         0       


itializing SD card...card initialized.
$PSRF150,1*3E
$GPGGA,,,,,,0,00,,,M,0.0,M,,0000*48
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPGSV,3,1,12,01,00,000,,02,00,000,,03,00,000,,04,00,000,*7C
$GPGSV,3,2,12,05,00,000,,06,00,000,,07,00,000,,08,00,000,*77
$GPGSV,3,3,12,09,00,0,,,,N*53
$GPGGA,,,,,,0,00,,,M,0.0,M,,0000*48
$GPGSA,A,1,,,,,,,,,,,,,,,*1E
$GPGSV,3,1,12,01,00,000,,02,00,000,,03,00,000,,04,00,000,*7C
$GPGSV,3,2,12,05,00,000,,06,00,000,,07,00,000,,08,00,000,*77
0,*71
$GPRMC,,V,,,,,,,,,,N*53

I gotbthis to work - patience is the key...


0    410  40.754219  -73.997261  1349 05/28/2014 02:19:04 209  34.20  343.78 6.48  S     5568     51.24  NE    10807 162       0       
0    410  40.754219  -73.997261  1359 05/28/2014 02:19:05 225  34.20  343.78 6.48  S     5568     51.24  NE    10837 162       0       
0    410  40.754219  -73.997261  1369 05/28/2014 02:19:06 246  34.20  343.78 6.48  S     5568     51.24  NE    10868 162       0       
0    410  40.754219  -73.997261  1379 05/28/2014 02:19:07 267  34.20  343.78 6.48  S     5568     51.24  NE    10898 162       0       
0    410  40.754219  -73.997261  1390 05/28/2014 02:19:08 285  34.20  343.78 6.48  S     5568     51.24  NE    10929 162       0       
0    410  40.754219  -73.997261  1400 05/28/2014 02:19:09 308  34.20  343.78 6.48  S     5568     51.24  NE    10960 162       0       
0    410  40.754219  -73.997261  1410 05/28/2014 02:19:10 327  34.20  343.78 6.48  S     5568     51.24  NE    10990 162       0       
0    410  40.754219  -73.997261  1420 05/28/2014 02:19:11 350  34.20  343.78 6.48  S     5568     51.24  NE    11021 162       0       
0    410  40.754219  -73.997261  1430 05/28/2014 02:19:12 370  34.20  343.78 6.48  S     5568     51.24  NE    11051 162       0       
0    410  40.754219  -73.997261  1441 05/28/2014 02:19:13 393  34.20  343.78 6.48  S     5568     51.24  NE    11082 162       0       
0    410  40.754219  -73.997261  1451 05/28/2014 02:19:14 410  34.20  343.78 6.48  S     5568     51.24  NE    11113 162       0       
0    410  40.754219  -73.997261  1461 05/28/2014 02:19:15 430  34.20  343.78 6.48  S     5568     51.24  NE    11143 162       0       
0    410  40.754219  -73.997261  1471 05/28/2014 02:19:16 449  34.20  343.78 6.48  S     5568     51.24  NE    11174 162       0       
0    410  40.754219  -73.997261  1481 05/28/2014 02:19:17 469  34.20  343.78 6.48  S     5568     51.24  NE    11204 162       0       
0    410  40.754219  -73.997261  1491 05/28/2014 02:19:18 490  34.20  343.78 6.48  S     5568     51.24  NE    11235 162       0       
0    410  40.754219  -73.997261  1502 05/28/2014 02:19:19 512  34.20  343.78 6.48  S     5568     51.24  NE    11266 162       0       
0    410  40.754219  -73.997261  1512 05/28/2014 02:19:20 532  34.20  343.78 6.48  S     5568     51.24  NE    11296 162       0       
0    410  40.754219  -73.997261  1522 05/28/2014 02:19:21 555  34.20  343.78 6.48  S     5568     51.24  NE    11327 162       0       
0    410  40.754219  -73.997261  1532 05/28/2014 02:19:22 573  34.20  343.78 6.48  S     5568     51.24  NE    11357 162       0       
0    410  40.754219  -73.997261  1542 05/28/2014 02:19:23 594  34.20  343.78 6.48  S     5568     51.24  NE    11388 162       0       
0    410  40.754219  -73.997261  1553 05/28/2014 02:19:24 613  34.20  343.78 6.48  S     5568     51.24  NE    11419 162       0       
0    410  40.754219  -73.997261  1563 05/28/2014 02:19:25 633  34.20  343.78 6.48  S     5568     51.24  NE    11449 162       0       
0    410  40.754219  -73.997261  1573 05/28/2014 02:19:26 688  34.20  343.78 6.48  S     5568     51.24  NE    11494 162       0       
0    410  40.754219  -73.997261  1585 05/28/2014 02:19:28 905  34.20  343.78 6.48  S     5568     51.24  NE    11541 162       0       
0    410  40.754219  -73.997261  1597 05/28/2014 02:19:29 12   34.20  343.78 6.48  S     5568     51.24  NE    11572 162       0       
0    410  40.754219  -73.997261  1607 05/28/2014 02:19:30 31   34.20  343.78 6.48  S     5568     51.24  NE    11602 162       0       
0    410  40.754219  -73.997261  1617 05/28/2014 02:19:31 54   34.20  343.78 6.48  S     5568     51.24  NE    11633 162       0       

Patience is the key, but what was the solution? Was it a loose connection, code error, etc.?

Hi

Looks like it was the environment- I moved outside and had a clear view of the sky- that was last night - and today it's back to square one-

not getting a fix on a satellite - getting date/time/stamp - but even that takes a few minutes

back to the drawing board- I'll post my progress

one observation:

I did notice that you have transposed A1 and A0

So, then this is the correct pin layout?

static const int GPS_RXPin = A1;
static const int GPS_TXPin = A0;

This unit is taking about 90 to 120 seconds to lock for me, and I had to go outdoors. Testing indoors wasn't locking.

Hope this helps