Overview of theRaspberry Pi

Models 3B & 2B(Let's look at the hardware!)

Rick Commo, K7LOGMax Vaughan, KF7MAX

Overview of the Pi

Overview of the Pi

Overview of the Pi

● What's really different between the original 2B and the 3B?

Parameter Pi 2B (not the V1.2) Pi 3B

Architecture Cortex-A7(32 bit)

Cortex-A53(64 bit)

CPU Speed 900MHz 1200MHz

RAM Speed 450MHz 900MHz

Internal Wi-FiAnd Bluetooth

USB dongles Internal

● And how does that affect performance?

– Pi 3 is faster than the 2B, anywhere from 10% to 60%.

Overview of the Pi

● micro-SD cards formats

– FAT32● Required for the Raspberry Pi

– ExFAT● Windows: FAT32 up to 32GB then ExFAT

● 8GB recommended minimum.

● The size/cost sweet spot is around 16GB.

● Available in speeds of 2MBps thru 90MBps.

● Class 10 / U1 are common and priced well.

– Consider this a minimum for a good experience!

Overview of the Pi

● SD & microSD card speeds:

Overview of the Pi

● The Pi runs on 5V from an external source.

– Internally it generates 3.3V and 1.8V for chips.

● 5 Vdc

– Wall warts @2.5A with micro-USB connector

– USB power supply - USB to micro-USB cable

– GPIO pins – 5Vdc to pin_2 & Gnd to pin_6● Not preferred, but can be done – be careful!

● 12 Vdc

– 5V regulator & wire into the micro-USB● Can wire into the GPIO as above, but not preferred.

Overview of the Pi

● There are 2 GPIO pins marked 3.3 V.

– Don't even think of using these as 3.3 V inputs!

● For shack and emergency use

– Need around 5W-7W for the Pi itself under heavyCPU load plus any additional power for peripheralsto the Pi.

– Consider solar to battery to 5V for uninterrupted use● Might be a case for wiring to GPIO pins, but solderable

micro-USB are available.

Overview of the Pi

● USB Keyboard & Mouse

– To save a Pi port, use a cheap USB-2 compatiblehub.

● PS2 Keyboard & Mouse

– Use a PS2-Y to USB cable.

● Video

– HDMI is the default on first boot..● Lots of small, inexpensive HDMI displays available.

– Can be set to composite video connector viasoftware.

– Display Serial Input (DSI) port

Overview of the Pi

● 4 USB-2 ports

● There is a single USB-2 port on the CPU chipitself.

– The user USB ports, and the Ethernet port, allconnect to the CPU via a USB-2 hub chip.

● USB-2 has a max. throughput of 480Mbps orroughly 40+ Mbps.

– A lot of that 480Mbps is eaten up with overheadmanaging the numerous ports on a single USB-2channel.

– The reality is something like a real 260Mbps ofaggregate throughput.

Overview of the Pi

● 10/100Mbps Ethernet port

● Standard RJ45 connector

● Connects to the CPU via the USB-2 hub chip.

● Support for Ethernet built into the OS.

● Initially set to DHCP, but can be set to a staticaddress by editing /etc/dhcpcd.conf.

● Append something like this at to the end of thefile.

Overview of the Pi

● Native audio connector uses a form of PWM toproduce both channels, and there is no audioinput.

● Much better off using a USB to audio adapter:

– A board like the UDRC from NW Digital Radio.

– A small USB-audio adapter (provides audio into to thePi as well).

Overview of the Pi

● WiFi

– Built into the Pi 3 (802.11n)● Built-in supported with Compass and Raspbian.

– USB dongles for the Pi 2 (802.11b/g/n)● Some dongles supported by OSes, but may need a

driver, depending on the dongle.

● Bluetooth

– HW built into the Pi 3 (Bluetooth 4.1).

– USB dongles for the Pi 2

– Compass Linux pre-installs the Bluetooth service.

Overview of the Pi

● Pi 2 and Pi 3 have the 40 pin GPIO port (J8)

– Power/Ground pins: 12

– Digital pins: 28● Some GPIO pins are multi-functional. The function is set

when an app initializes the them.● Pins by functional group

– GPIO / 17 pins– UART / 2 pins– SPI / 5 pins– I2C / 2 pins– HAT EEPROM I2C / 2 pins

Overview of the Pi

● GPIO Pin numbering on header.

Overview of the Pi

● Display Serial Input (DSI) port

– Raspberry Pi Foundation ● 7” diagonal / 800 x 480 pixel

– This is too small for many apps, for example fldigi.● 10 point touch capability.● Price is typically $80, but can be had cheaper.

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Overview of the Pi

● Camera Serial Input (CSI) port

– Supported as part of Raspbian OS.

– A number of cameras available.● Ex: Raspberry Pi Foundation Camera Board V2

(Under $30 on Amazon.)– 8 MP– Available with and without an IR filter (night vision).

Overview of the Pi

● With the power supply turned off or unplugged

– Insert the microSDHC card into it's slot.

– Connect the mouse and keyboard.

– Connect the video screen (HDMI assumed).

– Connect the Ethernet cable (if hardwiring).

– Insert the Micro-USB power plug into the Pi.

– Turn on or plug in the power supply.

● At this point you should see the Pi booting upon your video screen.

Overview of the Pi

Demonstration

Overview of the Pi

Questions?