Show HN: AutoLISP interpreter in Rust/WASM – a CAD workflow invented 33 yrs ago

The first two were complimentary. Before that I was laying out PCB's by hand using (who can remember?) Vector tools and Xacto knives. Switching to ACAD with AutoLISP-based automation was a game changer.

Broadcast facilities are not very different from data centers, in the sense that you have loads of racks filled with equipment. I would say that one of the key differences was that the equipment was not as homogenous as it might be in data centers. Back then I was very involved in some massive studio projects, both in terms of facility design (not the architecture, the design and installation of the technology) and custom software/hardware for the same industry. Once again, in the early days all wiring diagrams were being done the old fashion way, with pencil and D-size paper on a drawing table.

I started with ACAD version 1.0 or 1.1, I can't remember. This ran on an 8086 CPM computer build on an S-100 frame. It actually had an 8087 math coprocessor board and another board with 512K (you read that right) of RAM to mount as a RAM disk. The computer had 64K of RAM. So, yeah, early ACAD ran on a system with 64K of RAM.

The studio AutoLISP software was the most extensive. It took advantage of 3D features to do such things route cables between equipment in different racks and rooms as well as compute the required cable lengths. It would generate cable cut lists and labels for the wiring crew, etc.

This also included managing a symbol library for these designs, much as a tool like KiCAD or Altium (which has now officially gone to shit!) manages both schematic symbol and PCB footprints for ECAD work. The equipment definitions included such things as input/output signal types, required cable type, connector types, wiring schematic and rack mount models (for laying out where in the racks each device would be installed).

This is work that I evolved over years as we designed and built many installations across the country. It was a valuable internal tool with competitive advantages. We left that industry behind a very long time ago, but I remember that time fondly. Technology was evolving at breakneck speed and there were incredible opportunities to develop innovative solutions across the entire technology stack, from embedded all the way up to custom equipment.

I can tell you that a good number of the design drawings for the higher floors in the Venetian resort in Las Vegas were assembled with AutoLisp scripts. The scripts I created grabbed components from other drawings that were already made to assemble a first pass set of drawings for floors that hadn't been fully designed yet, since the floors all had components of other floors.

They were still in the design process for the upper floors, while the lower floors had already been finished and they were moving up the building.

https://imgur.com/a/niXkSt7

It shows that per-connector metadata that was added to each equipment symbol. The metadata allowed AutoLISP to do some really cool and intelligent things.

The PCB layout tool had interesting constraints. One of the issues was that pad graphics took up way too much memory. So, what I had to do, was to layout PCB's using a symbol that consisted of two lines forming an X instead of real pads. The symbol name encoded the diameter, hole size, etc.

When the layout was done, I had to unload a bunch of modules and then run an AutoLISP routine that would find and replace all "PAD_NNNN_X" symbols with real "PAD_NNNN" symbols before plotting.

Once ACAD migrated to Windows this was no longer an issue. Of course, by that time, accessible ECAD tools were around. I think my last ACAD schematic and layout was somewhere around 1993. I just didn't have the money to invest in ECAD tools of the era, so my ACAD tool served a purpose.