GPRS Notes
===

Raspberry Pi B

| RPi Pin | RPi GPIO | FONA |
|-----|-----|------|
| 1 | 3.3V | Vio |
| 6 | Ground | Ground |
| 8 | GPIO14 (TXD) | RX |
| 10 | GPIO15 (RXD) | TX |

RPi Initial Setup
---

`rpi-serial-console` script provided in this directory.

```
sudo bash
rpi-serial-console disable
apt-get update
apt-get install-y ppp screen elinks minicom
```

Connect RPi to FONA once it's wired:

```
screen /dev/ttyAMA0 115200
```

or 

```
minicom -c on -D /dev/ttyAMA0 -b 115200
```

Make sure to turn off hardware flow control.

PPP Config Setup
---

Still as root:

```
cat > /etc/ppp/peers/fona <<EOF
connect "/usr/sbin/chat -v -f /etc/chatscripts/gprs.fona -T internet
115200
noipdefault
usepeerdns
defaultroute
persist
noauth
nocrtscts
local
EOF

cat > /etc/ppp/chat/gprs.fona <<EOF
# You can use this script unmodified to connect to cellular networks.
# The APN is specified in the peers file as the argument of the -T command
# line option of chat(8).

# For details about the AT commands involved please consult the relevant
# standard: 3GPP TS 27.007 - AT command set for User Equipment (UE).
# (http://www.3gpp.org/ftp/Specs/html-info/27007.htm)

ABORT           BUSY
ABORT           VOICE
ABORT           "NO CARRIER"
ABORT           "NO DIALTONE"
ABORT           "NO DIAL TONE"
ABORT           "NO ANSWER"
ABORT           "DELAYED"
ABORT           "ERROR"

# cease if the modem is not attached to the network yet
ABORT           "+CGATT: 0"

""              AT
TIMEOUT         12
OK              ATH
OK              ATE1

# +CPIN provides the SIM card PIN
#OK             "AT+CPIN=1234"

# +CFUN may allow to configure the handset to limit operations to
# GPRS/EDGE/UMTS/etc to save power, but the arguments are not standard
# except for 1 which means "full functionality".
#OK             AT+CFUN=1

OK              AT+CGDCONT=1,"IP","\T","",0,0
OK              ATD*99#
TIMEOUT         22
CONNECT         ""
EOF

pon fona
```

Setup for Boot
---

Still as root:

```
cat > /etc/network/interfaces.d/fona <<EOF
auto fona
iface fona inet ppp
  provider fona
```


References
---

* [TinySine 3G/GPRS/GSM Shield for Arduino with GPS - American version SIM5320A](http://www.tinyosshop.com/3g-gprs-gsm-shield-for-arduino-sim5320a)
* [Youtube: Setting up Adafruit FONA on a Raspberry Pi](https://www.youtube.com/watch?v=NArpvpmmpUU)
* [Adafruit: FONA Tether to Raspberry Pi](https://learn.adafruit.com/fona-tethering-to-raspberry-pi-or-beaglebone-black)
* [Adafruit: ](https://learn.adafruit.com/adafruit-fona-3g-cellular-gps-breakout)
* [Adafruit: Adafruit FONA 3G Cellular Breakout - American Version](https://www.adafruit.com/product/2687)
* [Amazon: DIYmall RPi 3g GPRS GSM expansion board sim4320a](https://www.amazon.com/DIYmall-Raspberry-Expansion-SIM5320A-American/dp/B06Y3N1BD6/)