1, performance and efficiency
We can expect that Raspberry Pie 5 will start with a brand-new system-on-chip design to improve performance or efficiency or both. The BCM27 1 1 chip of Raspberry Pi 4 has four Arm Cortex-A72 cores running at 1.5GHz. Its successor can provide some simple things, such as improving the clock speed: Raspberry Pi 400.
A circuit board variant built in a keyboard cabinet with integrated cooling function. Push the revised version of the same chip to1.8 GHz–amateur overclockers can easily push it to the same part to 2GHz or higher.
2. New core IP
Another possibility is to switch to newer core IP. Arm's Cortex-A76 claims that its performance is up to 35% higher than that of the equivalent Cortex-A75, which means that it is 20% faster than Cortex-A73 and 30% faster than the BCM27 1 1 chip used in Raspberry Pi 4 B. All these provide full backward compatibility with Cortex-A72.
3, coprocessor
The company can also add additional processing cores, just as it did in the transition from single core to quad core in Raspberry Pi 2. These may be full-speed kernels and low-performance boosting kernels for background tasks.
Even a special accelerator: Raspberry Pi now has an internal application specific integrated circuit (ASIC) ——RP2040 microcontroller, and co-founder Eben Upton once said that future products "very likely" include the performance aimed at improving the machine learning workload.
4. There is no new RAM option.
What is unlikely to change is the amount of RAM available. The previous Raspberry Pi board was up to 1GB, while the Raspberry Pi 4 was up to 4GB when it was launched, and the 8GB model was recently launched. The core of the chip supports more, but there is no 16GB module suitable for mass production-and there is almost no room for two 8GB modules to be placed side by side on a narrow board.
Although some directions of Raspberry Pi are clear, others are not clear. More in line with the wishes of fans, the following functions of competitors will keep Raspberry Pi 5 in a better state.
5. PCIe connection
It is a safe bet that the next generation of Raspberry Pi will be faster: every model launched, except the ultra-compact Raspberry Pi Zero series and Raspberry Pi Pico microcontroller development board, is faster and more efficient than its predecessor.
6. Power over Ethernet (PoE)
Another function required by users is native power over Ethernet (PoE) support. At present, only the top hardware connection (HAT) add-on board can be used. Integrating PoE directly into the circuit board will simplify the wiring of network applications, but it will increase the size-and may break the long-standing release price of the board of $35.
Raspberry Pi's future development board has another possible direction. Although this is not impossible, it is unlikely to appear in Raspberry Pi 5: that is, it will completely switch from Arm to free and open source RISC-V instruction set architecture (ISA).
7. RISC-V architecture
Raspberry Pi is an education-oriented organization, and it is no secret that they are interested in RISC-V: the company joined RISC-V International as a member as early as 20 19.
Although they may do so only to support this work, their membership may also indicate that they want to build their own chips based on RISC-V ISA-perhaps using chips designed by their internal ASIC team.
Upton played down this possibility. In an interview in 2020, he pointed out that "there is a huge difference between building a truly excellent microcontroller and building the simplest application processor". "10 times the engineering difference." Upton stressed.
However, this will bring several benefits, the most important of which is that the SoC based on RISC-V designed by the company's internal engineers will not attract the royalties currently paid to Arm. It also helps to make the Raspberry Pi series more open, and even helps to educate all aspects from ISA and chip design to low-level programming.
However, it will also destroy the famous backward compatibility of Raspberry Pi series. Even today, you can take out the microSD card with 32-bit version of Raspberry Pi OS from Raspberry Pi 4 and put it into the original Raspberry Pi (even the unpublished Alpha board) and make it start normally.
This did not stop the company's competitors. Although the commercial release of the open hardware BeagleV Starlight board has been cancelled, Radxa has confirmed its own plan to launch a RISC-V Raspberry Pi similar board with Linux function-while the target price of other companies in the industry is as low as $ 15.
No matter which of these predictions (if any), one thing seems clear: it is unlikely that the Raspberry Pi series will lose its position as the best-selling single-board computer series in the short term.