The Last of The Line

On 14/05/2007 23:38, Rod Smallwood wrote: I don't remember there ever being an 18MHz KDJ11-A. The variants of the KDJ11-A differ in CPU and ASIC revision, which determines whether an FPJ11 works in them. -AA (M8192) doesn't work with FPJ11, -AB (M8192-YB) does but was supplied without one fitted, and -AC (M8192-YC) was factory-fitted wioth one. The suffixes can be confusing, not least because on other microPDP-11 machines (KDF11-B) the -Bx suffix relates to the ROM set not the board design. The -BB is the 15MHz board without FPU (as delivered by the factory) but capable of using one; it's an M8190-AB. The -BC is the same board but different ASICs and/or CPU and won't work with an FPU (M8190 with no suffix). The -BF and -BE are the 18MHz board, all of which should work with an FPU, and as supplied in 11/83s all had one fitted -- these are all M8190-AE. I suspect -BF denotes the one with the later version 7.0 (instead of 6.0) ROMS, but I'm less sure about that. The suffixes on the handle tell you about the board revision. It's true that MicroPDP-11/73s used the 15MHz -BB board and had the 6.0 ROM set (and were supplied with QBus memory), and the original MicroPDP-11/83s ran at 18MHz (and were supplied with PMI memory) but these sometimes got upgraded over time, so looking at the suffix on the handle won't necessarily tell you what ROMs are in them, or whether it has an FPJ11, and the ROMs won't tell you the speed. Also, there were two versions of the KDJ11-D, with 0.5MB and 1.5MB of memory, and matching variants of the KDJ11-S. I'm sure the different version of the KDJ11-E all had the same number of SLUs. Only one can be configured to be the console port, of course -- perhaps that's why you've seen one described as "one console port" rather than "8 SLUs". Look in the Field Guide, which Megan Gentry maintains. However, I have a one-page list on paper somewhere which summaries the board size, capacity, number of address bits, refresh capability, parity capability, and PMI capability of most QBus memory. -- Pete Peter Turnbull Network Manager University of York