The amazing PicoPuter emulation project can run a transputer emulator on multiple Raspberry Pi Picos and group them using the transputer’s native interprocessor connection protocol.
The Raspberry Pi Pico is a surprisingly powerful device at $4 each, and one of its lesser-known features is its eight programmable IO state machines on board. As programmer archaeologist Andrew Menadue wrote in a blog post:
So he went and made it happen. One of the 133MHz ARM Cortex-M0+ cores of each pico runs a modified version of the T4 transputer emulator, and the PIO state machines run that
os-link Communication channels between processors, separately and without loading the CPU.
These inter-chip channels were one of the key features of the revolutionary transputer processors, such as the reg mentioned when profiling the device’s lead architect a decade ago. Transputers were used to build multiprocessor computers, where each microprocessor had its own local memory along with fast connections to its four neighboring chips capable of parallel processing. This was chic for the 1980s.
Menadue has also created a series of seven videos showing the process of building the hardware and getting the software up and running. He also shared the source code on GitHub. He’s even designed and built a RAM upgrade board for the Pi Pico that piggybacks onto one end of the tiny board and adds another 8MB of RAM. Since existing extensions for larger Pis are already called “Hats”, he named this extension “Underpants”.
One of the many notable elements of his setup is that he used original Inmos IMSC011 silicon to connect the transputer links to a PC via an Arduino and he also showed that his interface worked just as well with original transputers -Hardware communicates.
Although the transputers themselves were not a commercial success, a lot of software and hardware emerged from the project, including the now open-source parallel operating system HeliOS and the parallel programming language Occam. In the 1980s, transputers were used to add additional grunt to both Atari and Amiga hardware. More recently, the design of the processors inspired the XMos XCore processor, which is used, among other things, as a coprocessor in a modern Amiga. ®
The term “programmer archaeologist” comes from Vernor Vinge’s classic novel A Fire Upon the Deep. The definition, a few paragraphs long, is here on Goodreads and is worth reading – as is the novel.