MIT CADR simulator What is this? ------------- This is a program was originally written by Brad Parker <brad@heeltoe.com>, and is designed to emulate the MIT CADR microprocessor hardware and peripherals. The CADR is a second generation MIT Lisp Machine, and a good description can be found at https://lm-3.github.io/cadr.html . This program interprets the microcode found in the machine starting with the boot PROM which runs when the machine is first powered on. The PROM microcode loads additional microcode from the simulated disk and then boots the load band. There is sufficient hardware support for the disk and network to provide a reasonaly functional Lisp Machine experience. Quickstart ---------- Grab the pre-made disk image and run as "./usim". Enter the data and time and press "F1" and "F7" to clean up the display. You're up! If you want to use the network download and run chaosd; see https://github.com/lm-3/chaos . Keyboard bindings ----------------- Keys are mapped in the following manner by default: esc Alt Mode f1 Terminal f2 System f3 Network f4 Abort f5 Clear Input f6 Help f7 Page f8 f9 f10 f11 f12 pgup Break pgdn {appears to crash usim} home Call end End backspace rubout backspace Rub Out To enable/disable "MORE processing": Terminal-M Toggle **MORE** processing. Terminal-0-M Disable **MORE** processing. Building -------- UNIX-like systems: Just run "make". Everything else: Unsupported. Making a disk ------------- It is recommend to use the distributed disk image unless you understand the structure of a Trident disk. The program "diskmaker" will interpret a disk image partition table and make a new disk using a template file. The distributed disk was made using the default template. The template file basically feeds all the parameters to "diskmaker" to build a valid disk image an populate it with microcode and a load band. Running ------- Everything basically works. The simulator will boot a load band and talk on the (simulated) network. The emulation is reasonably complete (modulo bugs). It gets through the boot PROM code, loads the microcode band, copies the band to swap and executes the load band cleanly. The system boots and runs. The console display is drawn into an X11 window which tracks the mouse and keyboard. The simplest way to run it is ./usim You can make a warm start state file with ./usim -S Run the emulator, enter the date and time. Then C-c twice. The memory state will be saved in "usim.state". You can then warm start to come up quickly: ./usim -w Note that the warm start state file is intimately connected to the disk image. If the two are mismatched bad things will happen. The two files should be portable across different host operating systems. The disk emulation reads from a "disk image" file which is constructed with "diskmaker". The disk image looks like a Trident T-300 disk to the microcode, complete with a parition table. The TV board and IOB are emulated. An X11 window displays in monochrome at 768x1024. The mouse and keyboard are tracked. The keyboard is "mapped" to the old Knight keyboard. The internal microsecond clock and the 60hz TV interrupt currently try and use wall clock time for a more realistic simulation. There is also emulation of the Chaosnet board. Packets are sent via a Unix socket to a Chaos daemon which distributes them to various client programs (see https://github.com/lm-3/chaos). There are some hacks for noticing Unibus access but no Xbus/Unibus mapping support. There's still a long delay when booting the distributed world. The system is available right away, however, try "F2-p". If you are impatient try the warm start state file, but be sure to use it with it's matching disk image! The mouse emulation works but doesn't track exactly. What programs are here? ----------------------- usim - the CADR emulator diskmaker - program to make Trident disk images for the MIT CADR from a microcode (MCR) file, and a load band (LOD) readmcr - utility to read MCR file lod - utiltity to pick apart load bands and show their insides lmfs - raw hack to read files from (Symbolics) LMFS paritition cc - crude CADR debugger program Recent Changes -------------- v0.10 - TBD v0.9 - Minor speedups. Mac OSX (little endian) fixes. Warm start support (usim.state). Mouse/microcode synchronization (thanks to Devon for the idea) v0.8 - Speedups and bug fixes. chaosd/FILE server supports rebuilding sources from server. Can now resize screen. v0.7 - Added raw X11 support. Bjorn Victor's new keyboard configuration code. Diskmaker now takes a template file and will show info on existing disk images. v0.6 - Better network support. Standing on the Shoulders of Giants ----------------------------------- I (Brad Parker) would like to thanks the following people for helping me on this, er, project: Tom Knight Howard Shrobe Richard Greenblatt Danial Weinreb Al Kossow George Carrette Steve Krueger Alastair Bridgewater John Wroclawski Bjorn Victor Devon Sean McCullough Without their support or encouragement I would probably not have done this. Certainly if Al had not sent me the PROM images I would never have started. And without Dan's box-of-tapes I could never have succeeded. RG offered some good explainations when I was confused. TK and Howie were extremely supportive at the just right moment (and answered a lot of email). George offered many good suggestions and answered lots of questions. Steve helped me locate missing pages from "memo 528". Alastair did some amazing work on several explorer emulators. Bjorn has used the code, offered many suggestions, fixes and improvements. And John's office is where I first saw a 3600 console and said, "what's that?".