LTE project gets a status bar!

In my continuing effort to learn about programming, cellular service, and Arduino, I’ve made a couple of great developments on my LTE project. Essentially, I’m turning these parts into a texting/gps device. I want to say a phone, but since it uses LTE only, it can’t actually make a phone call. So it is a “smart device” rather than a “smart phone”.

Of course, any useful device needs to have a status bar. And that is what I have done so far. The Nokia 5110 display, at the current font, supports 5 lines of text. So, I decided the top line will always be the status bar. Just like your smart phone, this device uses a status bar to tell you the “status” of everything you really, really need to know in one glance.

The first digits displayed are the battery percentage. If you don’t know how much time you have left on the device before it dies, it can be a little hard to use. Here you can see the magic behind the curtain:

// Get the battery percentage:
uint16_t vbat;
if (! fona.getBattPercent(&vbat)) {
Serial.println(F(“Failed to read Batt”));
lcd.print(“**% “);
} else {
Serial.print(F(“VPct = “)); Serial.print(vbat); Serial.println(F(“%”));
lcd.print(vbat); lcd.print(“% “);
}

Next up is the GPS indicator. Note that this doesn’t tell you if you have a lock, but does tell you if the battery draining GPS is turned on or off (GPS for on, — for off). Fortunately, the fona library includes a GPS status checking function, so we just call it, like so:

// Get the GPS status:
int statGPS = fona.GPSstatus(); Serial.print(F(“GPS status = “)); Serial.println(statGPS);
if (statGPS == 1) {lcd.print(“GPS “);} else {lcd.print(“— “);}

After that, we have the network status indicator. I’ll delve into that a bit more. It looks like the traditional multi-bar display, but unlike traditional ones on your smart phone, this actually is just full bars, or not. As you can see, you can get different letters for different status, or just the home made bar indicator glyph for roaming or home connections.

// Get the network status:
uint8_t n = fona.getNetworkStatus();
Serial.print(F(“Network status “));
Serial.print(n);
Serial.print(F(“: “));
if (n == 0) {Serial.println(F(“Not registered”)); lcd.print(“X”);}
if (n == 1) {Serial.println(F(“Registered (home)”)); lcd.write(0);}
if (n == 2) {Serial.println(F(“Not registered (searching)”)); lcd.print(“S”);}
if (n == 3) {Serial.println(F(“Denied”)); lcd.print(“D”);}
if (n == 4) {Serial.println(F(“Unknown”)); lcd.print(“?”);}
if (n == 5) {Serial.println(F(“Registered roaming”)); lcd.write(0);}
lcd.print(” “);

Finally, there is a number that tells you how many text messages you currently have.

// Get the number of SMS messages:
int8_t smsnum = fona.getNumSMS();
if (smsnum < 0) {
Serial.println(F(“Could not read # SMS”));
lcd.print(“-0- “);
} else {
Serial.print(smsnum); Serial.println(F(” SMS’s on SIM card!”));
lcd.print(smsnum);
}

You are welcome to check out the whole commit, but this is the gist of how the status bar works. Currently, the sketch takes up 78% of the Arduino’s memory. I think the direction I am going with this is trying to make a beginning to end, build at home smart device that allows you to at lease navigate by GPS, and send/receive text messages.

If wishes were fishes, and moose’s excuses, I guess we would all have full freezers. With that said, if I am able, I wish I could work in a couple other simple tasks as well, such as a way to play a simple game, perhaps check an email, or maybe a very rudimentary e-link style web browser. But I think that might be a whole lot more than I can realistically accomplish with so little memory on the device. We’ll see though!

Linux – keep it simple.

Arduino LTE Botletics shield and a Nokia 5110 display!

image2

Today was a lot of fun, and I mean a lot! I was able to connect not only the Botletics LTE shield, but also the Nokia 5110 screen to the Arduino, AT THE SAME TIME! I know, for the rest of the Arduino enthusiasts out there, this may seem like child’s play, but it was a big deal for me.

First, I was using the Botletics modified fona library, and with the soldered board pins, it can only connect to the Arduino one way. The problem was that I was also using the PCD8544 library to control the Nokia 5110 display, but some of the pins needed were the same ones for both devices. That certainly wouldn’t do. So, I edited the PCD8544.h file as follows:

PCD8544(uint8_t sclk = 3, // clock (display pin 2)
uint8_t sdin = 4, // data-in (display pin 3)
uint8_t dc = 5, // data select (display pin 4)
uint8_t reset = 12, // reset (display pin 8)
uint8_t sce = 13); // enable (display pin 5)

Changing these pin outs allowed me to control it with the remaining pins on the board. Now I can have both the display and the LTE shield at the same time! Essentially, the old PCD8544 library had used pins 3,4,5,6, and 7, for simplicity. I however couldn’t use 6 and 7, as those were taken by the LTE shield. So, I swapped them in the header file to point to pins 12 and 13, since they were not being used.

The only problem I ran into, though, was space. It takes a lot of space for the fona library to run the LTE shield. Originally, I was going to use the U8 library, but using those two together actually took 109% of the storage space on the Arduino Uno. I tried to trim down the portions of code for the fona side, but couldn’t get everything small enough. Fortunately, the PCD8544 library was much, much smaller, and I found that it even has a simpler interface for text only, which is mostly what I want to use the screen for.

With those two libraries pared up, I added some lines to my LTE demo sketch to allow me to display the battery information on the Nokia 5110 screen. All told the sketch uses 26470 bytes (82%) of the program storage space, the maximum is 32256 bytes. It worked great, looked good, and still leaves room for more programming.

You can check out the full commit, of course, but here is the portion about the screen:

case ‘b’: {
// read the battery voltage and percentage
uint16_t vbat;
if (! fona.getBattVoltage(&vbat)) {
Serial.println(F(“Failed to read Batt”));
} else {
lcd.setCursor(0, 0);
lcd.print(“Battery Status”);
Serial.print(F(“VBat = “)); Serial.print(vbat); Serial.println(F(” mV”));
lcd.setCursor(0, 1); lcd.print(“VBat = “); lcd.print(vbat); lcd.print(” mV”);
}

if (! fona.getBattPercent(&vbat)) {
Serial.println(F(“Failed to read Batt”));
} else {
Serial.print(F(“VPct = “)); Serial.print(vbat); Serial.println(F(“%”));
lcd.setCursor(0, 2); lcd.print(“VPct = “); lcd.print(vbat); lcd.print(“%”);
}

break;
}

Really simple commands to set up the cursor, and then just lcd.print to display information. I really like this simple screen library for text. It doesn’t handle graphics too well, though, which is what the U8 library excelled at.

So I guess now I need to work out some sort of menu system, as well as some sort of buttons if I want to turn this thing into a portable texting/gps/data interface device.

Linux – keep it simple.

Testing other SIM cards with the Arduino LTE shield from Botletics

IMG_20190423_084454

In the continuing process of testing out various aspects of using the Botletics LTE Arduino shield, I’ve decided to do a quick test with a few other SIM cards that I have available. I tested two other options, my Straight Talk SIM card, and a Freedom Pop SIM card. I was particularly interested in the Freedom Pop card, since that would allow me to have a free option for my board.

The first thing I did was add the following lines to my sketch, to handle the APN’s:

//fona.setNetworkSettings(F(“your APN”), F(“your username”), F(“your password”));
//fona.setNetworkSettings(F(“m2m.com.attz”)); // For AT&T IoT SIM card
//fona.setNetworkSettings(F(“telstra.internet”)); // For Telstra (Australia) SIM card – CAT-M1 (Band 28)
fona.setNetworkSettings(F(“hologram”)); // For Hologram SIM card
// WJH fona.setNetworkSettings(F(“fp.com.attz”)); // For Freedom Pop SIM card – Sort of works. Connects, but you need their app to text/call/sms/web/etc.
// WJH fona.setNetworkSettings(F(“tfdata”)); // For Straight Talk SIM card – sort of works. Connects and sends/receives SMS, but no web data.

That way, I just un-comment whichever option I need, and flash that to the board. Note that there are other options that I think you can pass for APN controls, but these three options (APN, user name, password) are the only ones this sketch accepts.

Here was the results of my test. Starting with Freedom Pop:

FONA> C
—> AT+CCID
<— ***************
SIM CCID = ***************
FONA> 1
—> AT+CPSI?
<— +CPSI: LTE CAT-M1,Online,310-410,0×9308,125708560,61,EUTRAN-BAND12,5110,3,3,-16,-98,-65,10
—> AT+COPS?
<— +COPS: 0,0,”AT&T”,7

OK FONA>
n
—> AT+CGREG?
<— +CGREG: 0,1
Network status 1: Registered (home)
FONA> i
—> AT+CSQ
<— +CSQ: 24,99
RSSI = 24: -66 dBm
FONA> R
—> AT+CMGF=1
<— OK
—> AT+CPMS?
<— +CPMS: “SM”,0,10,”SM”,0,10,”SM”,0,10
FONA> s
Send to #***************
Type out one-line message (140 char): test FP
—> AT+CMGF=1
<— OK
—> AT+CMGS=”<MYPHONE#>”
<— >
> test FP
^Z
Sent!
FONA> R
—> AT+CMGF=1
<— OK
—> AT+CPMS?
<— +CPMS: “SM”,0,10,”SM”,0,10,”SM”,0,10
FONA> w
URL to read (e.g. dweet.io/get/latest/dweet/for/sim7500test123):
http://www.google.com
****
—> AT+HTTPTERM
<— OK
—> AT+HTTPINIT
<— OK
—> AT+HTTPPARA=”CID”
<— OK
—> AT+HTTPPARA=”UA”
<— OK
—> AT+HTTPPARA=”URL”
<— OK
—> AT+HTTPACTION=0
<— OK
Status: 601
Len: 0
—> AT+HTTPREAD
<— OK
Failed!
FONA>

And Straight Talk:

FONA> n
—> AT+CGREG?
<— +CGREG: 0,1
Network status 1: Registered (home)
FONA> 1
—> AT+CPSI?
<— +CPSI: LTE CAT-M1,Online,310-410,0×9308,125708560,61,EUTRAN-BAND12,5110,3,3,-18,-98,-64,8
—> AT+COPS?
<— +COPS: 0,0,”HOME”,7

OK FONA>
w
URL to read (e.g. dweet.io/get/latest/dweet/for/sim7500test123):
http://www.google.com
****
—> AT+HTTPTERM
<— ERROR
—> AT+HTTPINIT
<— OK
—> AT+HTTPPARA=”CID”
<— OK
—> AT+HTTPPARA=”UA”
<— OK
—> AT+HTTPPARA=”URL”
<— OK
—> AT+HTTPACTION=0
<— OK
Status: 601
Len: 0
—> AT+HTTPREAD
<— OK
Failed!
FONA> s
Send to #***************
Type out one-line message (140 char): test 2 st
—> AT+CMGF=1
<— OK
—> AT+CMGS=”***************”
<— >
> test 2 st
^Z
Sent!
FONA>
+CMTI: “SM”,1
R
—> AT+CMGF=1
<— OK
—> AT+CPMS?
<— +CPMS: “SM”,2,30,”SM”,2,30,”SM”,2,30

Reading SMS #1
—> AT+CMGF=1
<— OK
—> AT+CSDH=1
<— OK
AT+CMGR=1
+CMGR: “REC UNREAD”,”+***************”,,”19/04/29,10:42:01-32″,145,4,0,0,”+12085978931″,145,13
test 2 st
***** SMS #1 (13) bytes *****
test 2 st
*****

Reading SMS #2
—> AT+CMGF=1
<— OK
—> AT+CSDH=1
<— OK
AT+CMGR=2
OK
Failed!
FONA>

What is more important is what all that garble means. Essentially, it boils down to this:

  • Freedom Pop connects instantly to the AT&T network. However, you can’t read data, and you can’t send or receive text messages.
  • Straight Talk connects instantly to the AT&T network. It does send and receive text messages, but it cannot use data. So, there is no way to support web interface or tunneling.

So, without further breaking it down, and just using the sketches as is, you can connect with both FP and ST, but only ST can send/receive text messages, and no data, so neither option seems to really work out of the box. If you’ve tried other options, be sure to let me know the results.

Linux – keep it simple.

Texting trouble with the LTE shield!

sim7000a

Next on my bucket list for things to test out with the Botletics LTE Shield was text messaging, or SMS. According to the demo, it was supposed to be really easy and straight forward, but it wasn’t.

First, I used the Hologram Dashboard to send an SMS message to the device. It “showed up” but I couldn’t read it:

FONA> R
—> AT+CMGF=1
<— OK
—> AT+CPMS?
<— +CPMS: “SM”,1,10,”SM”,1,10,”SM”,1,10

Reading SMS #1
—> AT+CMGF=1
<— OK
—> AT+CSDH=1
<— OK
AT+CMGR=1
OK
Failed!
FONA>

Then I tried sending one from the device:

FONA> s
Send to #<MYPHONENUMBER>
Type out one-line message (140 char): testing
—> AT+CMGF=1
<— OK
—> AT+CMGS=”<MYPHONENUMBER>”
<— >
> testing
^Z

Failed!
FONA>

And it wouldn’t send one either. I tried several variations of this for about an hour, and just wound up frustrated. Later, I took a look through prior issues, and I found another user who had the same problem. Turns out, in their situation, they originally connected to Verizon, and then couldn’t send or receive. Then they connected to AT&T, and they could send and receive. So, I took a look, and sure enough, I was connected to a Verizon network. I reset my board, and tried connecting again. This time (by no work of my own) it connected to an AT&T network, and I too could send and receive SMS messages! Check it out:

  • Sending – I received it on my phone in seconds!

FONA> s
Send to #<MYPHONENUMBER>
Type out one-line message (140 char): testing
—> AT+CMGF=1
<— OK
—> AT+CMGS=<MYPHONENUMBER>
<— >
> testing
^Z
Sent!
FONA>

  • Receiving – I sent the reply of “Cool!” from my phone.

FONA> r
Read #1
Reading SMS #1
—> AT+CMGF=1
<— OK
—> AT+CSDH=1
<— OK
AT+CMGR=1
+CMGR: “REC READ”,”+<MYPHONENUMBER>”,,”19/04/25,21:39:28+00″,145,4,0,3,”+19703769316″,145,5
FROM: +<MYPHONENUMBER>
—> AT+CMGF=1
<— OK
—> AT+CSDH=1
<— OK
AT+CMGR=1
+CMGR: “REC READ”,”+<MYPHONENUMBER>”,,”19/04/25,21:39:28+00″,145,4,0,3,”+19703769316″,145,5
Cool!
***** SMS #1 (5) bytes *****
Cool!
*****
FONA>

So, if you too are trying to follow the tutorial for the LTE demo using the Botletics SIM7000A shield, be sure you are hooked up to AT&T. Also, if you were hooked up to Verizon, be sure you unplug the Arduino, and the power supply/battery of the board. Otherwise, the modem might still be on!

Linux – keep it simple.

LTE shield for Arduino: Web Page Download!

IMG_20190423_084454

First up on my list of learning about this Botletics LTE shield was how to pull data. Fortunately for me, the LTE demo sketch included a method for downloading something from the internet. It works like this:

// The code below was written by Adafruit and only works on some modules
case ‘w’: {
// read website URL
uint16_t statuscode;
int16_t length;
char url[80];
flushSerial();
Serial.println(F(“URL to read (e.g. dweet.io/get/latest/dweet/for/sim7500test123):”));
Serial.print(F(“http://&#8221;)); readline(url, 79);
Serial.println(url);
Serial.println(F(“****”));
if (!fona.HTTP_GET_start(url, &statuscode, (uint16_t *)&length)) {
Serial.println(“Failed!”);
break;
}
while (length > 0) {
while (fona.available()) {
char c = fona.read();

// Serial.write is too slow, we’ll write directly to Serial register!
#if defined(__AVR_ATmega328P__) || defined(__AVR_ATmega168__)
loop_until_bit_is_set(UCSR0A, UDRE0); /* Wait until data register empty. */
UDR0 = c;
#else
Serial.write(c);
#endif
length–;
if (! length) break;
}
}
Serial.println(F(“\n****”));
fona.HTTP_GET_end();
break;
}

As the code states, it was originally written by Adafruit, and some portions of this code (the Adafruit Fona library) were updated by Timothy Woo of Botletics) and it allows you to look up a URL and download it. So, I tested Google. It downloaded it like so:

googleWebsite

And I copied/pasted it into a text file, and saved it as html, which opened in a browser, like this:

googletest

So, that works. Granted, using this method was extremely slow. I am using a serial monitor connection over USB at a 9600 baud rate, which really took a while to catch all of the data. You could literally watch the characters being written on the screen. However, I think the modem is much faster, just my interface to it is not as quick. I’ll have to play with it some more, but it was nice to be able to download a web page at least!

Linux – keep it simple.