Overview of the Raspberry Pi Models 3B & 2B

Transcription

1 Overview of the Raspberry Pi Models 3B & 2B (Let's look at the hardware!) Rick Commo, K7LOG Max Vaughan, KF7MAX

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4 What's really different between the original 2B and the 3B? Parameter Architecture CPU Speed RAM Speed Internal Wi-Fi And Bluetooth Pi 2B (not the V1.2) Cortex-A7 (32 bit) 900MHz 450MHz USB dongles Pi 3B Cortex-A53 (64 bit) 1200MHz 900MHz Internal And how does that affect performance? Pi 3 is faster than the 2B, anywhere from 10% to 60%.

5 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!

6 SD & microsd card speeds:

7 The Pi runs on 5V from an external source. Internally it generates 3.3V and 1.8V for chips. 5 Vdc Wall 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.

8 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 heavy CPU load plus any additional power for peripherals to 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.

9 USB Keyboard & Mouse PS2 Keyboard & Mouse To save a Pi port, use a cheap USB-2 compatible hub. 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 via software. Display Serial Input (DSI) port

10 4 USB-2 ports There is a single USB-2 port on the CPU chip itself. The user USB ports, and the Ethernet port, all connect to the CPU via a USB-2 hub chip. USB-2 has a max. throughput of 480Mbps or roughly 40+ Mbps. A lot of that 480Mbps is eaten up with overhead managing the numerous ports on a single USB-2 channel. The reality is something like a real 260Mbps of aggregate throughput.

11 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 static address by editing /etc/dhcpcd.conf. Append something like this at to the end of the file.

12 Native audio connector uses a form of PWM to produce both channels, and there is no audio input. 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 the Pi as well).

13 WiFi Built into the Pi 3 (802.11n) USB dongles for the Pi 2 (802.11b/g/n) Built-in supported with Compass and Raspbian. 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.

14 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

15 GPIO Pin numbering on header.

16 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. s

17 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).

18 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 up on your video screen.

19 Demonstration

20 Questions?