That 6805 series still lives in the form of the 'HC05 series from Motorola. It was the first real "high Integration" processor from Motorola, soon followed by the 6804, which was much cheaper. The 6801 was a higher level of integration than the Intel 8048 and was more flexible than the Intel 805x series which came out later. What I found really impressive about this Motorola line was that the physical size of the chip itself was so large. Motorola held introductory seminars about their newly introduced 68000 series and the 6805. I was all excited about the 68K at the time and didn't pay much attention to the 6805 series. I was duly impressed when I saw the product brocheure, which had an unpackaged chip on it. It was as large as my little fingernail! The 68000, by comparison, was small. I've built at most half a dozen 68K projects in the ensuing time, and by 1985 had turned out over two dozen applications for the 6805 series, particularly the P3 and U3. It's still quite a respectable family of devices, though its CMOS scions have done better than it did, probably for packaging reasons. The 6805 was the first processor that I treated strictly as a logic component, often using more than one with the same function just because it was easy to partition the tasks that way. It's in its twilight years now, though, as MOT has introduced the latest family of replacements for it, all cheaper because they use a single chip with differing bonding options, which holds the price down, and because they fit into small packages due to their die size. There's a lot to learn from these old microcontrollers and having a development system for them will be really handy if you get it to work. They've served in model railroads and home security systems. You find 'em everywhere. Dick ----- Original Message ----- From: Joe <rigdonj(a)intellistar.net> To: <classiccmp(a)classiccmp.org> Sent: Saturday, April 22, 2000 6:54 AM Subject: Re: Interesting finds; 1801, National Semiconductor RM-665, Grid,HPs.. Does