serv

ike Baidu, Huawei, or AliBaba". The strongest RISC-V story is a Chinese national security thing, and it works like this. — ⁂ — Most computer hardware has been designed and assembled in the PRC for several years now. In 02019 the USG imposed heavy sanctions on a number of PRC hardware companies, including https://en.wikipedia.org/wiki/Huawei, the largest telecommunications equipment manufacturer in the world and since 02020 the largest smartphone manufacturer in the world. These sanctions deprived Huawei of access to chips from TSMC in Taiwan, even though Taiwan is nominally not under US jurisdiction. Computer hardware relies heavily on trade with Taiwan and other countries, including, in particular, MCUs and CPUs fabricated at TSMC in Taiwan using designs licensed from ARM. ARM China, a former ARM subsidiary, has the legal right to license ARM designs for use within China but not overseas. Using a component makes you vulnerable to backdoors inserted by the component's manufacturer or, if you do not understand its design, its designer. Such backdoors are known to have been a major instrument of US foreign policy in the past (the Crypto AG affair) and presumably still are. The Huawei sanctions were justified by allegations that the PRC is doing the same thing. There are rumors that some manufacturers in the PRC are experiencing a new "onshore mandate" that prohibits foreign-sourced components, at least in some products; quoting https://www.cnx-software.com/2022/10/22/10-cents-ch32v003-ri...: > [the WCH CH32V003 is] quite timely as we were forced by HQ last Friday to revise all product line designs to comply with 100% Chinese domestic semiconductors & passive components by latest Q4 end. All western sourced/accounts and parts are now forbidden, apart from those sourced by HQ’s registered jurisdiction. > Worth adding to the list, we’ve also signed accounts with GigaDevice and Expressif Shanghai in the MCU and connectivity range. — ⁂ — So that's the problem to solve. RISC-V already offers PRC manufacturers a path to building ARM-competitive MCUs and low-end CPUs which can be legally sold overseas and which comply with this onshore mandate. As a bonus, they can be sold at prices several times cheaper than any ARM alternative; WCH's CH32V003 is reputedly 10¢, though LCSC doesn't seem to have them in stock yet. Presumably, until SMIC (or another domestic alternative) can move up to more modern process nodes, fully-sanctions-proof versions of these chips will be larger, more expensive, and more power-hungry than TSMC-manufactured chips. But for many applications this doesn't matter. The Allwinner D1, using a RISC-V design from the Honey Badger open-source hardware subsidiary of AliBaba, is already performance-competitive with early Raspberry Pis, though I think that performance relies on TSMC. In 3–5 years RISC-V might be able to move up to today's desktop or laptop CPUs, and SMIC might be able to fabricate things at early Raspberry Pi performance levels (22 nm? Something past the end of Dennard scaling, anyway). — ⁂ — Also, though, you shouldn't totally dismiss the FPGA cores. FPGAs are a lot cheaper than they used to be, thanks to Lattice. It's true that an ASIC MCU will always be faster than an FPGA fabbed in the same process running a softcore, but it may not have the peripherals you need, and there are a lot of applications where we run an MCU at a 32768 Hz clock to save power, so clock speed isn't everything. Olof Kindgren's bit-serial RISC-V core SeRV https://github.com/olofk/serv reputedly fits into 200 4-LUTs like those in the Lattice iCE40LP384, which would cost US$1.82–2.15 at Digi-Key if they had any: https://www.digikey.com/en/products/detail/lattice-semicondu... and that would leave you another 184 LUTs for peripherals. You can get MCUs a lot cheaper than US$2 but US$2 is still within the budget for a lot of projects. Every year there are more and more custom ASICs from more and more companies, and a lot of them include some kind of microcontroller core to orchestrate their activities. Historically this has often been something like an 8051 or Z80, but switching it to RISC-V seems likely to lower development costs significantly, especially if a tiny RV32I core like SeRV or the smaller configurations of PicoRV32 would be adequate.