Raspberry Pi Types – Compare the Different Models
| Wayne Chen
Some History: The Single-Board Computer
Dating back to 1976, a single-board computer (SBC) is a fully-integrated computer that has all the critical system components on a single circuit board. This is in contrast to the typical desktop computer configuration in that all of the system memory, CPU, GPU, network interfaces, and other I/O adapters are all one unit. In the typical desktop computer, most, if not all, components are connected via slots or cables to a mainboard.
The main advantages of SBC are cost, size, reliability and mass production capacity. These systems are designed as a single unit and are produced in large quantities. Therefore, the software and hardware executing on the system are more reliable.
Disadvantages are related to scalability, computing power, and application compatibility. Often, once the SBC design is complete, it is almost impossible to make any modifications or upgrades. Over time, computing technology is also evolving. However, since the SBC design is so dedicated, the hardware will soon become obsolete, except for specific applications.
The Raspberry Pi Foundation
When the founders of the Raspberry Pi Foundation began bringing computer science and digital technology education to young people in developing countries, the real magic of the SBC was here. They considered the advantages of SBC and combined it with the portability and flexibility of the Linux operating system to create what is now called the Raspberry Pi.
They saw an opportunity to teach computer science in an unprecedented way. Using a small ARM-based processor, a lively open source community, and the power of mass production, they offer a card-sized card for between $25 and $35. Even better, with the introduction of the new Raspberry Pi model, their developers can maintain future compatibility.
This means that all Raspberry Pis run on the same 5 VDC power supply and they share roughly the same form factor between generations. Although the current strength and power consumption of each model are different, it is sufficient to use a power converter with a rated current greater than 2 amps.
One thing to note before starting: With the exception of the first generation of Raspberry Pi, Models A versus B designate the form factors of the generation. Size A is compact, at 65.0 x 56.5 mm, whereas size B is standard at 85.6 x 56.5 mm.
Raspberry Pi 3: The Latest and Greatest
Raspberry Pi 3 Model B + is the latest and best SBC of the Raspberry Pi Foundation, offering the highest processor speed, embedded Wi-Fi, embedded Bluetooth, extended network capabilities, USB boot, and now Power over Ethernet (PoE) . This release is a much-needed upgrade in a feature set that provides a more integrated experience.
The model is unique in that it includes onboard Wi-Fi and Bluetooth modules. Prior to this release, the first thing everyone bought next to their new Raspberry Pi was the USB Wi-Fi adapter. This version allows you to release the USB slot by keeping the onboard Wi-Fi. In addition to more memory and processing power, the Raspberry Pi can also be booted from a USB stick without the need for an SD card.
Specifications:
- Processor & GPU:
- Quad-core Cortex-A53 @ 1.2 GHz
- Broadcom VideoCore IV @ 250 MHz
- Flash Memory & Storage:
- 1-GB SDRAM (shared with GPU)
- Micro SDHC slot (card not included)
- USB bootable
- Networking:
- 2.4-GHz and 5-GHz IEEE 802.11.b/g/n/ac wireless LAN
- Bluetooth 4.2/BLE
- Gigabit Ethernet over USB 2.0 (maximum throughput of 300 Mbps)
- I/O:
- 4-pole stereo audio/composite video output port
- 4 x USB 2.0 ports
- Full-size HDMI, MIPI DSI display port, MIPI CSI camera port
- Form Factor:
- Model A: 65.0 x 56.5 mm
- Model B/B+: 85.6 x 65.0 mm
Raspberry Pi Zero: The Minimalist
Raspberry Pi Zero is the smallest and cheapest software package in the Raspberry Pi Foundation. It provides a simple way for microcomputers to abandon standard GPIO, SD card, HDMI, camera I/O and micro USB. It lacks a feature set that makes up for size and price.
What makes this unit so special? size! At about the same length but half the width, the Raspberry Pi is stripped by peripherals, but has a strong sense of processing per gram. Pi Zero is a powerful and inexpensive device that trains young engineers and amateurs.
One might say that the lack of direct USB ports, Wi-Fi and other peripherals make it a less accessible mode for the masses. (It replaces the USB A port, which has USB Micro B as an input, so an adapter is required.)
Specifications:
- Processor & GPU:
- Flash Memory & Storage:
- 512-MB SDRAM (shared with GPU)
- Micro SDHC slot (card not included)
- Networking:
- $5 module:
- No onboard networking interface
- $10 module:
- Built-in 802.11b/g/n single-band 2.4-GHz wireless
- Bluetooth 4.1 BLE
- $5 module:
- I/O:
- Audio via mini HDMI or GPIO expansion
- 1 x micro USB port
- Mini HDMI 1080p60fps, MIPI CSI camera port
- Form Factor:
- Model B: 65.0 x 30.0 mm
Raspberry Pi 1: The Beginning
The original SBC from the Raspberry Pi Foundation, Raspberry Pi 1 Model B started all this. It is one of the first computers in this category and has opened up the world for millions of computer sciences. Although not as powerful as its successor, this small computer contains some important blows.
Because it is primitive, it has the least amount of RAM and processing power, but its lack of processing power makes up for the extra power. The unique composite output port makes it an excellent old-fashioned game simulator that is often used to rebuild a famous street cabinet project.
The reception of the first Raspberry Pi was welcomed in the developer and education markets. According to reports, as early as 2017, about 5 million units have been sold in these units! With such numbers, the open source community has become so rich and diverse that content is not surprising. The first generation of Raspberry Pi will always be called the small computer that started it.
Specifications:
- Processor & GPU:
- Flash Memory & Storage:
- 512-MB SDRAM (shared with GPU)
- SD, MMC, SDIO card slots (card not included)
- Networking:
- 10/100-Mbit/s Ethernet
- I/O:
- 4-pole stereo audio/composite video output port
- 2 x USB 2.0 ports
- HDMI (rev 1.3), composite video (RCA jack), MIPI display interface (DSI) for raw LCD panels
- Form Factor:
- Model A+: 65.0 x 56.5 mm
- Model A/B/B+: 85.6 x 65.0 mm
Raspberry Pi 2: The Rise
As the first major upgrade to the Raspberry Pi Foundation, the Raspberry Pi 2 Model B has been substantially improved in functionality, adding more USB ports, extending GPIO strips and more SDRAM. The Raspberry Pi 2 is able to execute more applications, including video processing that was previously impossible, to provide a true fulcrum for the evolving community.
The Pi 2 has a more professional and compact appearance, making the composite output seamless, leaving more room on the PCB. The added space allows for a second set of USB ports, which is arguably the most important connection on the Raspberry Pi.
However, this Pi has a small warning because it does not have an onboard Wi-Fi chip. Don't worry - it just means that one of the extra USB ports will be consumed by the compact Wi-Fi adapter.
The Raspberry Pi 2 also has the first significant advancement in processing power, from a single-core 700 Mhz ARM processor to a shiny new quad-core Cortex running at 900 Mhz. In addition, the second Raspberry Pi extends its RAM from 512 MB to up to 1 GB.
Specifications:
- Processor & GPU:
- Quad-core Cortex-A53 @ 900 MHz
- Broadcom VideoCore IV @ 250 MHz
- Flash Memory & Storage:
- 1-GB SDRAM (shared with GPU)
- Micro SDHC slot (card not included)
- Networking:
- 10/100-Mbps Mbit/s Ethernet
- I/O:
- 4-pole stereo audio/composite video output port
- 4 x USB 2.0 ports
- Full-size HDMI, MIPI DSI display port, MIPI CSI camera port
- Form Factor:
- Model B: 85.6 x 65.0 mm
At the end
Despite the small size and price, the Raspberry Pi can meet your project needs. Although there are other SBCs on the market, there is no one more popular follower and open source community than the Raspberry Pi.
If you have an old project you can use a new computer brain to control it, or if you want to create something new and try to decide which module you need, then Raspberry Pi is highly recommended.