The Cat in the Sun Sparc IPX

The FAQ for alt.folklore.computers mentions that there's a picture of a cat on the motherboard of the Sun Sparc IPX. Now, I happen to have one of those machines handy, so I thought it was time to try out a digital camera and get a few images for the Web. This page is the result.

The FAQ claims that the cat is inspired by the comic strip Calvin and Hobbes, but the cat in the strip is more like a tiger than the one in the IPX. Certainly a tabby, anyway.

Here's the IPX motherboard in full. The case folds open, and I've arranged it with the lid (containing the floppy and hard disk drives) on the left. The cat is just to the right of the large, black chip with the "LSI" name on it.

To see a larger version of the image (512x384, 63kb), click here (or on the thumbnail). To see the original, high resolution image (1024x768, 264kb), click here.

Here's a close-up of the cat and the few chips surrounding it. The chip just below is the AMD AM85C30 (originally designed by Zilog as the Z8530), which contains two of the IPX's serial ports. The cat is part of the silkscreen layer of the printed circuit board (PCB). Most PCBs are made from a fibreglass board with copper conductive tracks on both sides. On top of the copper is a layer of solder resist, often coloured green, whose function is to prevent solder blobs from bridging the connections to the chips. The final layer is known as the silkscreen and is formed from paint, white in this case, arranged to outline the positions of the parts and to label the connectors. The cat has probably been drawn using a computer-aided design (CAD) system, because it seems to be made up of straight lines, carefully arranged to approximate curves. PCB CAD programs and production machines are often limited to just drawing straight lines.

To see a larger version of the image (512x384, 54kb), click here (or on the thumbnail). To see the original, high resolution image (1024x768, 181kb), click here.