Our First Laser Printer

We decided to purchase a laser printer so we could print bill of materials sheets for each job. I managed to find a used HP LaserJet cheap. This was the original LaserJet printer model and had only 128K of RAM. This was fine, except if you wanted to print graphics. You could not even draw a half page of black and white graphics with 128K. This also meant that there was very little room to load fonts into the printer. The saving grace was that there was a font cartridge slot. I bought one of those super font cartridges that had lots of fonts. It turns out that we really only needed one font. I don't remember which one we used, but it was a small monospaced font.

The printer had a serial port, not a Centronics printer port. Normally this would have been considered a limitation, but this was perfect for our shop floor control system which I was building around Arnet multiport RS-232 cards.

I needed to learn just a little bit of Hewlett Packard's PCL (printer control language) to make the LaserJet do its thing. I wrote some code in Smalltalk to drive the printer. Depending on how complex the board design was, these bills of materials sometimes had a lot of information on them. It was somehow very satisfying to produce software that would drive a printer elsewhere in the building. I had never done that before.

The printer was located up in the engineering department, and after they designed a circuitboard for an order they would fill in some fields into the shop floor control system and print out the bill of materials on the LaserJet.

Christmas Vacation

I didn't take the plunge into Smalltalk right away. I wasn't completely sure it was the right choice. I was at the SoftPro store in Burlington in late 1988 and I noticed that they had a copy of the Smalltalk/V software from Digitalk. I asked them if they had any brochures, and they did. Three different full color, double sided marketing sheets. Very nicely done. Everything I saw about the language reminded me of Forth, but it had this idea of objects.

I wasn't about to ask my boss to buy yet another programming tool, so in December I bought it myself. I took the Tandy 1000SX home from work over Christmas vacation and dove into the Smalltalk/V manual, following the tutorial.

I was not disappointed. What an amazing language! I had never used anything so dynamic, or so graphical. Almost all the source code for each and every thing in Smalltalk is there. You can see it and you can modify it if you like. This was very compatible with my observation that Smalltalk and Forth were conceptually similar. The one surprise that really topped off this sundae with a cherry? Smalltalk has built-in multiprocessing. This was the ingredient that I sorely needed to produce the multiuser shop floor control system! What luck!