Technical Details

This section introduces the concepts and terms that are crucial for the understanding, implementation and use of Cellular IoT App Shield.

Band Details

SpecificationBG96
LTE-FDDB1/ B2/ B3/ B4/ B5/ B8/ B12/ B13/ B18/ B19/ B20/ B25①/ B26*/ B28
LTE-TDDB39 (for Cat M1 only)
eGPRS850/900/1800/1900Mhz
Embedded GNSSGPS/Galileo/QZSS 1575.42±1.023 MHz
GLONASS 1597.5~1605.8 MHz
BeiDou 1561.098±2.046 MHz
RegionGlobal
CertificationGCF/Vodafone (Global)
CE/Deutsche Telekom (Europe)
AT&T/ FCC/ PTCRB/T-Mobile /Sprint (North America)
RCM/Telstra (Australia)
IC/Telus/BELL (Canada)
Telefonica (Spain)
JATE/KDDI/SoftBank/TELEC/DOCOMO
(Japan)
KC/SKT/LGU+* (Korea)
IFETEL (Mexico)
IMDA (Singapore)
NCC (Taiwan)
CCC (China)

Warnings

  • ① LTE B25 will be supported on BG96 with R1.2 hardware version.
  • *Under Development

Connection Types

USB: If you don't want to occupy the UART port on the Raspberry Pi, just plug the shield via micro USB to Raspberry Pi. You can start to send and receive AT commands, transmit data, output GNSS NEMA, debug and upgrade firmware over the USB connection. It supports USB drivers for Windows, Linux, and Android. Details can be found in the drivers section.

UART: The UART pins will be available to use, with 3.3V power domain, directly connected to the UART port of Raspberry Pi. It can be used for data transmission and AT command communication with 115200bps baud rate. The default data frame format is 8N1 (8 data bits, no parity, 1 stop bit). This port does not provide GNSS data. The GNSS data can be gathered only over the USB.

Info
To use the UART follow the steps mentioned in the UART Configuration guide.

Data Speeds

  • Cat M1: Max. 375Kbps (Downlink), Max 375Kbps (Uplink)
  • Cat NB1: Max. 32Kbps (DL), Max. 70Kbps (UL)
  • EDGE: Max. 296Kbps (DL), Max. 236.8Kbps (UL)
  • GPRS: Max. 107Kbps (DL), Max. 85.6Kbps (UL)

SMS

Point-to-point MO and MT

SMS Cell Broadcast

Text and PDU mode

Enhanced Features

  • GNSS: GPS, GLONASS, BeiDou/Compass, Galileo, QZSS
  • Firmware Upgrade: via USB interface
  • DFOTA: Delta Firmware Upgrade Over the Air
  • Audio Record/Play
Warnings:
  • For the best working condition, use at least a 2A adapter or power source.
  • We don’t recommend the usage of long and low-quality micro USB cables between Cellular IoT Application Shield and Raspberry Pi. It causes data and power loss.
  • Do not apply higher voltages and currents than those specified absolute electrical values for sensor inputs and relay connections.

Pinout

Pinout image alt

Pin Descriptions

Pin NumberBCM PinPin NameDescription
25V5V PWRThis pin is connected to the 5V power net.
3GPIO 2SDAI2C Serial Data
45V5V PWRThis pin is connected to the 5V power net.
5GPIO 3SCLI2C Serial Data
7GPIO 41-WIREData line for communicate with 1-Wire sensors.
8UART RXBG96 TXThis pin functions as the serial data input to the module for UART communication.
10UART TXBG96 RXThis pin functions as the serial data output from the module for UART communication
11GPIO 17RELAYRelay control pin. When this pin is HIGH state, relay is operated.(Common and NO are connected.)
12GPIO 18IN-2When the voltage in the range 3.3-12V(max 15V!) is applied from the IN-2 input, this pin goes to LOW state. Default state is HIGH(pulled-up).
13GPIO 27USER LEDActive HIGH, to switch on the USER LED, the pin's state should be HIGH.
18GPIO 24USER BUTTONThis pin normally pulled-down to ground. When button is pressed, pin switches to LOW.
19GPIO 10IN-1When the voltage in the range 3.3-12V(max 15V!) is applied from the IN-1 input, this pin goes to LOW state. Default state is HIGH(pulled-up).
23GPIO 11BG96 PWRKEYThe module can be turned on by driving the pin BG96 PWRKEY to a HIGH-level voltage more than 500ms then pulling it down. You can apply the same process to power down to the module if it already powered up.
31GPIO 6BG96 APREADYAP_READY will detect the sleep state of the host (can be configured to HIGH level or LOW level detection). Please refer to AT+QCFG=“apready” command for details.
33GPIO 13BG96 RIWhen BG96 has URC to report, RI signal will wake up the host. Please refer to Chapter 3.14 for details about RI behavior from BG96 Datasheet.
37GPIO 26BG96 POWER ENABLEBG96 3.8V Power regulator control. Normally pulled-up, when this pin drove to LOW, BG96's power will cut off.
38GPIO 20BG96 STATUSThe STATUS pin is used to indicate the operation status of BG96 module. It will output HIGH level when the module is powered on.
6,9,14,25,30,34,39GNDGNDThis pins are connected to ground.

Electrical Characteristics of Pins

Pin NumberBCM PinPin NameDescriptionMinTyp.Max.Unit
25V5V PWRPower Supply4.855.25V
3GPIO 2SDAI2C Data33.33.6V
45V5V PWRPower Supply33.33.6V
5GPIO 3SCLI2C Clock33.33.6V
7GPIO 41-WIRE1-Wire data33.33.6V
8UART RXBG96 TXUART33.33.6V
10UART TXBG96 RXUART33.33.6V
11GPIO 17RELAYOutput33.33.6V
12GPIO 18IN-2Input33.33.6V
13GPIO 27USER LEDOutput33.33.6V
18GPIO 24USER BUTTONInput33.33.6V
19GPIO 10IN-1Input33.33.6V
23GPIO 11BG96 PWRKEYOutput33.33.6V
31GPIO 6BG96 APREADYInput33.33.6V
33GPIO 13BG96 RIInput33.33.6V
37GPIO 26BG96 POWER ENABLEOutput33.33.6V
38GPIO 20BG96 STATUSInput33.33.6V

Layout

Layout image alt

Dimension

Dimension image alt

LEDs

  • POWER (PWR): When the shield is powered up, this RED led turns on.
  • STATUS (STAT): While the module is powered up by driving PWRKEY(GPIO 11) to HIGH state or pushing the PWRKEY button, this RED led turns on.
  • USER (USER): The GREEN user led can be controlled by driving the GPIO 27 pin.
  • ENABLE(EN): This GREEN led shows the status of the power regulator of module is switched on or off. By default, the GPIO 26(ENABLE) pin is pulled up by hardware and the regulator juices the module. To shut down the regulator, this pin needs to be driven to LOW state.
  • NETLIGHT (NETL) : This BLUE led indicates the status of the module. When the connection is established and data is being transmitted/received, this led will blink at special intervals. Please find the following chart for details:
StateNetwork Status
Flicker slowly (200ms ON/1800ms OFF)Network searching
Flicker slowly (1800ms ON/200ms OFF)Idle
Flicker quickly (125ms ON/125ms OFF)Data transfer is ongoing
Always highVoice calling

Buttons

  • USER: This push button connected to GPIO24 and pulled up HIGH state by default. When you push the button, you will read LOW state from GPIO24.
  • PWRKEY: When BG96 is in power off mode, it can be turned on to normal mode by pushing the PWRKEY button for at least 500ms.
  • BOOT: Pushing this button can force the module to boot from USB port for firmware upgrade.

Sensors and I/O

3-axis 12-bit/8-bit Digital Accelerometer | MMA8452Q

3-axis 12-bit/8-bit Digital Accelerometer alt

  • The MMA8452Q is a smart, low-power, three-axis, capacitive, micromachine accelerometer with 12 bits of resolution. It has user selectable full scales of ±2 g/±4 g/±8 g with high-pass filtered data as well as non-filtered data available real-time.
  • The accelerometer connected to Raspberry Pi via I2C. The I2C address is 0x1C.
  • MMA8452Q's interrupt pins are not connected.

12-Bit Analog-to-digital Converter | ADS1015

  • The ADS1015 is precision, low-power, 12-bit, analog-to-digital converter.
  • Raspberry Pi can not measure analog inputs because it does not have internal ADC. However, with this external ADC, the ADS1015, you can read analog values with your Raspberry Pi.
  • The ADC connected to Raspberry Pi via I2C. The I2C address is 0x49.

Ambient Light Sensor | ALS-PT19

  • It's a phototransistor close responsively to the human eye spectrum, light to current.
  • It's connected to ADC (ADS1015), because it has an analog output and Raspberry Pi can not read it directly.
  • The sensor connected to AIN3 pin of ADS1015.

Temperature and Humidity Sensor | HDC1080

  • The HDC1080 is a digital humidity sensor with an integrated temperature sensor that provides excellent measurement accuracy at very low power.
  • Relative Humidity Accuracy ±2% (typical)
  • Temperature Accuracy ±0.2°C (typical)
  • The HDC1080 connected to Raspberry Pi via I2C. The I2C address is 0x40.
  • The heat that produced by when R.Pi heats up may cause the sensor to display a few higher degrees than the ambient temperature.

Relay

  • The relay for controlling high voltage and current.
  • Relay control pin is GPIO17. When this pin is HIGH, relay is switched and connected C and NO pins. When GPIO17 is a LOW state or unused, it connects C and NC pins.
  • This small form factor relay can handle up to 60W. Pushing the limits will harm the circuits and shield. Maximum contact ratings:
    • 12V DC - 5A
    • 24V DC - 2.5A
    • 120V AC - 0.5A
    • 220V AC - 0.25A

Isolated Inputs

  • Two isolated by optocouplers inputs available on the shield. Recommended max. The GPIO voltage level of Raspberry Pi is 3.3V. Reading higher than 3.3V voltage inputs are harmful for your Pi and will definitely destroy the circuits.
  • The upper limit of this inputs is 15V, between 3.3V and 15V is readable. GPIO pins are normally pulled up, when a voltage applied to isolated inputs, GPIO pins go LOW state.
  • The input's (sensor, switch, etc.) ground must be connected to optocoupler's G input to complete isolated circuits.

GNSS and Debug(DBG) UART Inputs

GNSS: This header pins directly connected to BG96 GNSS output. They are not connected to the UART port of Raspberry Pi. You should connect to BG96 via USB to receive GNSS data. Thinking that these pins might be needed somehow, so we've taken them out as headers.

Debug (DBG): This DEBUG UART port belongs to BG96 and used for embedded firmware debugging of the module and log output.

External I2C Header

When you need to add an external I2C thing, you can use these I2C connectors. 3.3V VCC and GND pins provided too. It has a pull-up resistor.

1-Wire Header

There are lots of sensors which have 1-Wire connection standard (DS18B20 etc.) in the market. The 1-Wire connector has VCC, DATA and GND pins. With these pins, you can connect easily a 1-wire sensor. The data pin directly connected to GPIO4 and has a 4.7K pull-up resistor.