This is a portable, open source emulator of the 32-bit Inmos T414/T800/T801/T805 Transputer family, and a host/file I/O Server that interfaces it to a host OS, providing boot/debug/IO facilities.
It runs on Apple macOS Catalina, Windows 10, Ubuntu 24.02, Linux Mint 21.3, and Raspberry Pi Debian 12. An embedded version of the emulator component is also available for the Raspberry Pi Pico 1. I do not have Mac hardware to support porting beyond Catalina; specifically no M1/M2/Mx. Due to lack of compatible TPM hardware, I cannot build on Windows 11 or later.
It is part of the Parachute Project.
It is written in C++14. I do not intend to move beyond this C++ version.
It used to build on Raspbian Stretch, the oldest OS I had when I started automated builds. This had Clang 3.5.0, which limited the C++ standard I could support.
Actively in development.
Currently working on compatibility with the aid of Mike Brüstle's Transputer Validation Suite.
Also adding debugging facilities to aid the completion of the eForth Transputer port, and adding a build for the Raspberry Pi Pico.
Attempting to run other typical Transputer software such as the Inmos occam and C compilers, and the port of Minix.
First release 0.0.1 Midsummer 2019 (13 June 2019) as part of Parachute 0.0.1.
Project started around 19/08/2005, with a long hiatus. Another hiatus from Sep 2021 to Dec 2022. Another hiatus from Dec 2022 to Jul 2023. Another hiatus from Dec 2023 to Aug 2024.
First release:
- A Cross Platform system that can run "Hello World" (via my NodeServer (custom protocol) implementation).
Second release (work in progress):
- Convert the NodeServer to be IServer compatible, implementing all frame types needed by "Hello World" and eForth. Similarly, convert "Hello World" and eForth to be IServer compatible.
- IServer is unfinished; it implements the following frame types:
- Id (Version)
- Exit
- Open
- Read
- Write
- Puts (put string with newline to a stream)
- Get Key
- Poll Key
- Close
- Command Line
- It implements the following "extended" frame types, not part of the original IServer, for performance purposes:
- Put Char (to the console stream)
- Note that the IServer's file handling does not yet prevent directory traversal vulnerabilities.
- Converting older C code (that's not very portable) to C++14 (that hopefully is more portable).
- eForth requires the following facilities of IServer (it originally accessed a UART; these routines have been
changed to use IServer protocol on Link 0):
- URD: Read and wait (odd return system)
- ?RX: Return input character and indication of whether there is any input available
- TX!: Send output character
- !IO: Initialise UART
- Allow validation using Mike's TVS and pass tests for all implemented instructions
- Add the start of a build for the Raspberry Pi Pico - that can run Hello World booted from a link; that has a single core, and single link over CDC-USB Serial. The memory/flash use is quantified.
Third release:
- Capable of running eForth.
- Note that the IServer's file handling does not yet prevent directory traversal vulnerabilities.
Fourth release:
- More IServer implementation.
- Prevent directory-traversal vulnerabilities in IServer's file handling - limit operations to under its root directory.
- Complete Integer functionality.
Fifth release:
- Complete Floating Point functionality.
- Complete IServer implementation.
0.0.2 Second Release (work in progress)
- Converting the NodeServer to be IServer compatible. Similarly, "Hello World" (see IServer/client-examples/hello-world-iserver).
- Release for macOS is upgraded from El Capitan to Catalina.
- Release for Intel Linux is now done only on Ubuntu 24.04.
- Release for Raspberry Pi is now done only on Debian 12.
- Release for Windows 10 is now done on Windows 10 22H2.
- Removed versions for older OSs (macOS El Capitan, Ubuntu 16.04, 18.04, CentOS 7.6, Raspbian Stretch).
- IServer -df (full debug) now enables all parts of the debug output.
- Successfully runs hello.asm !
- IServer now supports FPuts and the extended PutChar frame (used by eForth); it also supports CommandLine, for use by (e.g.) the Inmos compilers. Any IServer arguments that are not understood by IServer can be passed to the transputer on request.
- Added a "Hello World" example that uses the macro assembler's primary bootstrap include file. (see IServer/client-examples/hello-world-secondary-iserver)
- Added a "Hello World" example that can boot from ROM. (see IServer/client-examples/hello-world-iserver-rom)
- Bugfix: A loaded ROM's memory is now initialised/destroyed correctly.
- Emulator now allows a list of symbols to be loaded; these are displayed when disassembling or using the monitor; also enhancements for debugging eForth.
- The emulator's monitor now accepts a 't' command which toggles the display of disassembly and memory read/write.
- The emulator can run tests from Mike Brüstle's Transputer Validation Suite.
- Corrected several instruction implementations with guidance from TVS: add, adc, bitrevnbits, bitrevword, csngl, cword, div, ladd, ldiff, ldiv, lmul, lshl, lshr, lsub, lsum, mul, rem, shl, shr, sub, wcnt, xdble, xword.
- Implemented the instructions from "Transputer Instruction Set - Appendix".
- Add a build of the emulator for the Raspberry Pi Pico 1.
- Bugfix: protocol handler - open file - was inadvertantly broken on some platforms.
0.0.1 First Release
- Versioning and build now controlled by Maven and CMake.
- Successfully runs hello2.asm !
- Renamed emulator binary from t800emul to temulate.
- Started adding the T801 instructions, from "Transputer Instruction Set - Appendix, Guy Harriman".
- Started adding the T801/T805 instructions from "Support for debugging/breakpointing in transputers" (INMOS Technical Note 61). Added the -j flag to enable 'j 0' breakpoints.
- Described current implementation/missing status in the above section.
- The T810 instructions from "The IMS T810 - A Preliminary Survey" are not implemented.
- Builds using Maven/CMake/CLion on macOS (El Capitan +), Linux (Ubuntu 16.04, Ubuntu 18.04, CentOS 7.6, Raspbian Stretch), Windows 10.
- Added Boot-from-ROM, fixed Wdesc bug after boot from link.
- Fixes: xword, call, j & scheduling (with assistance from Michael Brüstle), locations of TPtrLoc1, TPtrLoc0. csngl and xdble: correct detection of sign of Areg
- Monitor: db (renamed from da), dw improvements, added w (workspace display), added b/b+b-/b? (breakpoints), added s (show all state).
- Adopted the Apache License v2.
- Since the assembler understands offset addressing, the manual building of offset operands has been changed from: j 'label - _XX1' _XX1: to: j label
....
- IServer client library in tmasm assembler
- Iserver needs to support terminal I/O facilities (no echo key reads, sensing available readable keys) for eForth
- j and cj - resolve the operand into an address that would be jumped to, display it
- Emulate multiple Transputers on 1-N physical cores
- Link topology management
- Develop debug interface
- Write debugger program
- Add memory-mapped frame buffer via SDL
- Add mouse interface for same
- Investigate Benes networks
- Remove potential buffer overflows in cpu.cpp (what were these?)
- Refactoring: make use of isLegalMemory within memory.cpp
- Unfinished: resetch when given a link not a memory channel
- The debug/release configuration switch does not appear to be doing anything other than setting an appropriate build directory.
- None known.
- Rework example code with IServer protocol library.
- Write some!
Although the emulator recognises all T414/T800/T801/T805 instructions, not all are currently implemented. The greatest omission is floating point - this is an integer T805 at the moment!
The proposed T810 instructions are not implemented.
Those that are not implemented emit a diagnostic when encountered.
See the sections 'Implemented Instructions' and 'Unimplemented Instructions' below.
It is my intention to eventually implement the complete instruction set, such that it completely passes the Transputer Validation Suite. My focus is on the common integer instructions, those that support communications, process management, diagnostics, and then the floating point instructions.
Direct: adc, ajw, call, cj, eqc, j, ldc, ldl, ldlp, ldnl, ldnlp, nfix, opr, pfix, stl, stnl.
Operations: add, alt, altend, altwt, and, bcnt, bitclt, bitrevnbits, bitrevword, bsub, ccnt1, clrhalterr, csngl, csub0, cword, diff, disc, diss, dist, div, dup, enbc, enbs, enbt, endp, fpentry, fpuclrerr, fpuseterr, gajw, gcall, gt, in, ladd, lb, ldiff, ldiv, ldpi, ldpri, ldtimer, lend, lmul, lshl, lshr, lsub, lsum, mint, move, mul, not, or, out, outbyte, outword, prod, rem, ret, rev, runp, saveh, savel, sb, seterr, sethalterr, shl, shr, startp, sthb, sthf, stlb, stlf, stoperr, stopp, sttimer, sub, sum, talt, testerr, testhalterr, tin, wcnt, wsub, wsubdb, xdble, xor, xword.
From the Transputer Instruction Set - Appendix: start, testlds, teststs.
T414: cflerr
T805: break, clrj0break, lddevid, ldmemstartval, pop, setj0break, testj0break.
Nonstandard emulator: emuquery, marker, terminate, toggledisasm, togglemonitor
fpchkerr, fptesterr, resetch, taltwt.
fpuexpdec32, fpadd, fpb32tor64, fpchki32, fpdiv, fpdup, fpeq, fpgt, fpi32tor32, fpi32tor64, fpint, fpldnladddb, fpldnladdsn, fpldnldb, fpldnldbi, fpldnlmuldb, fpldnlmulsn, fpldnlsn, fpldnlsni, fpldzerodb, fpldzerosn, fpmul, fpnan, fpnotfinite, fpordered, fpremfirst, fpremstep, fprev, fprtoi32, fpstnldb, fpstnli32, fpstnlsn, fpsub, fpuabs, fpuchki64, fpudivby2, fpuexpinc32, fpumulby2, fpunoround, fpur32tor64, fpur64tor32, fpurm, fpurn, fpurp, fpurz, fpusqrtfirst, fpusqrtlast, fpusqrtstep, norm, testpranal.
From the Transputer Instruction Set - Appendix: testhardchan, testldd, testlde, teststd, testste,
32-bit Transputers: fmul.
T414: ldinf, postnormsn, roundsn, unpacksn.
T800: crcbyte, crcword, move2dall, move2dinit, move2dnonzero, move2dzero.
T805: timerenableh, timerenablel, timerdisableh, timerdisablel.
T810: checkaddr, delay, dislinkinth, dislinkintl, distimesl, enlinkinth, enlinkintl, entimesl, fpmacc, fpxprod, ldhw, macc, pause, sthw, xprod
ldc, ldpi, dup, adc, rev, ldnl, gcall stl, ldl, wcnt, gajw, mint, clrj0break, timerdisableh, timerdisablel, toggledisasm, outbyte, outword, ldlp, in, terminate, cj, sb, and, eqc, lb, not, or, xor, lsum.
tests: 54, ok: 46, fail: 8
adc PASS
add PASS
alt PASS
and PASS
bcnt PASS
bitcnt PASS
bitrevnbits PASS
bitrevword PASS
bsub PASS
ccnt1 PASS
cflerr PASS
crcbyte unimplemented FAIL
crcword unimplemented FAIL
csngl PASS
csub0 PASS
cword PASS
diff PASS
div PASS
dup PASS
eqc PASS
fmul unimplemented FAIL
gt PASS
ladd PASS
ldc PASS
ldiff PASS
ldinf unimplemented FAIL
ldiv PASS
lmul PASS
lshl PASS
lshr PASS
lsub PASS
lsum PASS
mint PASS
mul PASS
norm unimplemented FAIL
not PASS
or PASS
postnormsn unimplemented FAIL
prod PASS
rem PASS
rev PASS
roundsn unimplemented FAIL
shl PASS
shr PASS
sub PASS
sum PASS
talt PASS
unpacksn unimplemented FAIL
wcnt PASS
wsub PASS
wsubdb PASS
xdble PASS
xor PASS
xword PASS
Full documentation to follow.. but in the meantime...
Basically, given a binary boot file, then in two terminal sessions:
- iserver -ld -df bootfile.bin # The -ld -df is 'debug mode'.
- temulate -df -ld -t # Ditto. -t terminates on memory violation.
The emulator waits for its boot file, down link 0. It then runs it. The iserver sends the boot file, then switches to handle its host I/O protocol down link 0.
Run iserver or temulate with -? or -h to get their command line summaries.
To run the 'hello world' client program:
In one terminal window...
$ cd IServer/client-examples/hello-world-iserver $ tmasm -b hello.bin -l hello.lst hello.asm Pass 1: Creating model from 245 macro-expanded/included line(s) End of Pass 1: Checking for unresolved forward references Pass 2: Updating model with 0 pass 2 section(s) End of Pass 2 Writing binary file hello.bin Start address 0x8000006F End address 0x80000162 Writing listing file hello.lst
$ iserver hello.bin (does not return)
In second terminal window... $ temulate $ (automatically returns, as the 'terminate' instruction is the last executed in hello.asm)
The first terminal window should now show: $ iserver hello.bin hello world (still does not return) Ctrl-C <<- you'll have to interrupt it. $
The source is split into the following directories:
Shared - utility code that is common to many parts of the system.
IServer - the client and server portions of the file/host I/O server and its protocol definition. The server runs on your host computer (i.e. under Windows, Linux, macOS etc.). The client runs under Transputer emulation as part of your application; it's an assembly language include file.
Emulator - the T414/T800/T801/T805 emulator.
The distribution currently builds under the following systems:
- Apple macOS - Intel only
- 'Catalina' 10.15
- (untested on more recent versions)
- Linux
- Linux Mint 21.3 Intel x86-64
- Ubuntu Linux 24.04 LTS Intel x86-64
- Raspberry Pi Debian 12
- Microsoft Windows
- Windows 10 22H2
- (untested on earlier versions e.g. XP, 7, 8, 8.1)
- Due to lack of compatible TPM hardware, I cannot build on Windows 11 or later.
- Embedded microcontrollers
- Raspberry Pi Pico (cross-compiled on Ubuntu Linux 24.04)
The build is controlled by CMake, with a Maven wrapper around this to work with my CI server, and to make the main build commands a little easier to use (standard mvn lifecycle commands vs CMake oddities). Maven is just doing some preprocessing (the version number of the project is set in the pom.xml; mvn extracts this and embeds it in the C++ code), running cmake in various stages, and is used for packaging and overall build control. It's just much easier with it..
You can ignore the Maven side completely, you'll just have to use arcane commands.
Both types of build are shown below.
C++ Dependencies:
- These are all downloaded and built by CMake External Projects:
- Google Test and Google Mock
- gsl-lite (C++ Guidelines Support Library from https://github.com/gsl-lite/gsl-lite#as-cmake-package)
Prerequisites:
-
All Operating Systems:
- Git (to clone the transputer-emulator repository, and for CMake to download GoogleTest). Command line tool git needs to be on the PATH.
- Python (prefer 3.x but 2.x is fine; required by the GoogleTest build). Command line interpreter python needs to be on the PATH.
- Java 17 JDK (for Maven).
- Optional: Apache Maven. I use 3.9.9. Command line tool mvn needs to be on the PATH. It's recommended to download the latest binary release from https://maven.apache.org/download.cgi and unzip it, placing its bin directory on the PATH.
- CMake. I use 3.10.3+ .. 3.25.1. Command line tool cmake needs to be on the PATH.
- If you want to build the client-examples programs, you'll need the DevZendo.org Transputer Macro Assembler installed and on your PATH.
- The TMPDIR environment variable must be set to something on all POSIX systems, or some tests will fail.
-
macOS 'Catalina' 10.15:
- CMake 3.29.5 (from MacPorts)
- GNU Make 3.81 (from XCode command line tools)
- clang (e.g. via XCode Developer tools). Apple clang version 12.0.0 (clang-1200.0.32.29)
- If you see messages like this in a build failure: "Ignoring CMAKE_OSX_SYSROOT value: /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.15.sdk because the directory does not exist." Then this is due to recent XCode removing the version directory - as root, do: cd /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs ln -s MacOSX.sdk MacOSX10.15.sdk
-
Windows 10 Home:
- Microsoft Visual Studio Build Tools 2017, v 15.9.28307.423 (cl 19.16.27027.1 for x64) Note this doesn't need the full Visual Studio, these are just the command line tools. The command line tools must be set up in your command line environment. In my shell, I run: "C:\Program Files (x86)\Microsoft Visual Studio\2017\BuildTools\VC\Auxiliary\Build\vcvarsall.bat" x86_amd64 prior to running other commands.
- CMake is installed in C:\Program Files\CMake
- Maven is installed in C:\Program Files\apache-maven-3.9.9
- (these locations are noted in the pom.xml).
- Note if you're using CLion, set your Visual Studio Toolchain architecture to amd64. Otherwise you'll get errors saying your compiler can't create a simple executable.
-
Ubuntu 24.04, Linux Mint 21.3:
- G++ 11 etc: apt-get install build-essential g++-11 make cmake
- CMake: install it via apt, and create symlinks /opt/cmake/bin/cmake -> /usr/bin/cmake and /opt/cmake/bin/ctest -> /usr/bin/ctest .
-
Debian 12 Raspberry Pi:
- G++ 11 etc: apt-get install build-essential g++-11 make cmake
-
Raspberry Pi Pico (build on Ubuntu 24.04)
- The Pico SDK and toolchain:
apt install gcc-arm-none-eabi libnewlib-arm-none-eabi build-essentialThe Pico SDK should be cloned from https://github.com/raspberrypi/pico-sdk Set thePICO_SDK_PATHenvironment variable to point to this copy of the Pico SDK. The Pico Extras should be cloned into the directory alongside the SDK from https://github.com/raspberrypi/pico-extras Set thePICO_EXTRAS_PATHenvironment variable to point to this copy of the Pico Extras. i.e. the pico-sdk and pico-extras clones are siblings. CMake can be installed from apt, no need for a manual install.
- The Pico SDK and toolchain:
The typical install location is:
- macOS/Linux: /opt/parachute
- Windows: C:\parachute
- Raspberry Pi Pico: temulate.uf2 - copy it to your Pico with BOOTSEL held down
To build, cd to the top level directory (where this README.md is) and do:
On windows: vcvarsall.bat as shown above.
Then for desktop builds (e.g. macOS - adjust for Windows):
Using CMake directly:
setup:
mkdir -p target/classes
cp src/main/resources/* target/classes
edit target/classes/version.cpp and change ${project.version} to the version shown near the top of pom.xml
generate:
mkdir cmake-build-debug
cd cmake-build-debug
cmake -G "Unix Makefiles" -D NOCROSS=true /path/to/transputer-emulator
cd ..
compile:
cmake --build cmake-build-debug --target all
test:
ctest --test-action Test --parallel 8 --verbose
Using the Maven wrapper:
setup/generate/compile:
mvn clean compile -P build
test:
mvn test -P build
package:
mvn package -P build
NOTE: if you have a test failure from testfilesystem, set the TMPDIR environment variable to /tmp.
For Raspberry Pi Pico:
mvn -DCROSS=PICO clean compile -P build
The Maven build will:
- download all dependencies and plugins (quite a few of these),
- create the version number header (the version is controlled by the maven pom.xml)
- creates the shared library code that contains the project version, in the target/classes directory, then
- run this for you:
- cd cmake-build-debug; cmake .. (ie regenerate the cmake cache)
- cmake --build cmake-build-debug --target all -- -j 4
This build will build the entire system: T800 emulator and iserver, client libraries, etc. (Only the emulator is built for Rasperry Pi Pico.)
This doesn't install it on your system - see below.
To clean:
mvn clean
To install into the default install location, you'll need to have permission to create it and write files there. e.g. on macOS/Linux:
$ sudo mkdir /opt/parachute
Password: <enter your password, assuming you have sudo rights>
$ `sudo chown myuser:myuser /opt/parachute # e.g. Linux
$ sudo chown myuser:staff /opt/parachute # e.g. macOS
e.g. on Windows: In File Explorer, create C:\parachute and set it writable by your user account, however you do this.
Then to copy the built software there:
mvn -P local-install prepare-package
This installation location is defined in the operating-system-specific profile sections of the pom.xml.
This project would not have been possible without the hard work and inspiration of many individuals.
Notably, thanks to:
Michael Brüstle of transputer.net for invaluable assistance with details of the T800, idiosyncrasies of its operation, aspects of undefined behaviour, for finding problems with timer queue addresses - and for maintaining a superb archive. Also for granting access to the Transputer Validation Suite (which is not for redistribution).
Dr. Barry Cook, formerly of Keele University, for starting my interest in the transputer, and for my final year undergraduate Computer Science project, also a transputer emulator (with different goals).
The transputer designers, and all at Inmos/ST who developed it.
Authors of other emulators:
Julian Highfield for his T414 emulator which may be found at https://web.archive.org/web/20130515034826/http://spirit.lboro.ac.uk/emulator.html
Gavin Crate's various emulators based on microcode and Julian Highfield's emulator, which may be found at https://sites.google.com/site/transputeremulator/Home
Andras Pahia's continuation of this emulator which may be found at https://github.com/pahihu/t4
Andrew Menadue's 'picoputer' extension of Andras' emulator to run on the Raspberry Pi Pico, connected to real Inmos IMSC011 link adapters; this may be found at https://github.com/blackjetrock/picoputer
Henry S. Warren, for "Hacker's Delight".
Pete Warden for his investigation and documentation into the Raspberry Pi Pico memory layout at https://petewarden.com/2024/01/16/understanding-the-raspberry-pi-picos-memory-layout/
Yury Shevchuk and Roman Pozlevich for the gcc-t800 port, ttools and libxputer packages. These were used throughout an earlier version of the project, for bootstrap code, object and executable file format and loader.
[CWG] "Transputer Instruction Set - A Compiler Writer's Guide" http://www.transputer.net/iset/pdf/tis-acwg.pdf
"Transputer Instruction Set - A Compiler Writer's Guide - Errata" http://www.transputer.net/iset/errata/tis-acwg-errata.txt
"Transputer Instruction Set - Appendix, Guy Harriman" http://www.transputer.net/iset/appendix/appendix.pdf
"Support for debugging/breakpointing in transputers" (INMOS Technical Note 61) http://www.transputer.net/tn/61/tn61.pdf
[TTH] "The Transputer Handbook", Ian Graham, Gavin King http://www.transputer.net/iset/isbn-013929134-2/tthb.pdf
"IMS T805 32-bit floating point transputer" http://www.transputer.net/ibooks/dsheets/t805.pdf
"Transputer Versions - Mike's Technical Note 2, Michael Brüstle" http://www.transputer.net/tn/m02/tdiff.pdf
"The IMS T810 - A Preliminary Survey, Guy Harriman" http://www.transputer.net/fbooks/t810pre/t810pre.pdf
"Transputer Development System, second edition" http://transputer.net/prog/72-trn-011-01/tds2nd.pdf
"Hacker's Delight, second edition, Henry S. Warren" https://www.pearson.com/en-us/subject-catalog/p/hackers-delight/P200000000672/9780321842688
This code is released under the Apache 2.0 License: http://www.apache.org/licenses/LICENSE-2.0.html.
(C) 2005-2024 Matt J. Gumbley
Mastodon: @[email protected]